diff --git a/LICENSE b/LICENSE
index 0990b3694b94ab..8e59136b1dd5a5 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1505,3 +1505,28 @@ The externally maintained libraries used by Node.js are:
     ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
     OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
   """
+
+- node-fetch, located at deps/node-fetch, is licensed as follows:
+  """
+    The MIT License (MIT)
+
+    Copyright (c) 2016 David Frank
+
+    Permission is hereby granted, free of charge, to any person obtaining a copy
+    of this software and associated documentation files (the "Software"), to deal
+    in the Software without restriction, including without limitation the rights
+    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+    copies of the Software, and to permit persons to whom the Software is
+    furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included in all
+    copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+    SOFTWARE.
+  """
diff --git a/deps/node-fetch/CHANGELOG.md b/deps/node-fetch/CHANGELOG.md
new file mode 100644
index 00000000000000..188fcd399db90e
--- /dev/null
+++ b/deps/node-fetch/CHANGELOG.md
@@ -0,0 +1,266 @@
+
+Changelog
+=========
+
+
+# 2.x release
+
+## v2.6.0
+
+- Enhance: `options.agent`, it now accepts a function that returns custom http(s).Agent instance based on current URL, see readme for more information.
+- Fix: incorrect `Content-Length` was returned for stream body in 2.5.0 release; note that `node-fetch` doesn't calculate content length for stream body.
+- Fix: `Response.url` should return empty string instead of `null` by default.
+
+## v2.5.0
+
+- Enhance: `Response` object now includes `redirected` property.
+- Enhance: `fetch()` now accepts third-party `Blob` implementation as body.
+- Other: disable `package-lock.json` generation as we never commit them.
+- Other: dev dependency update.
+- Other: readme update.
+
+## v2.4.1
+
+- Fix: `Blob` import rule for node < 10, as `Readable` isn't a named export.
+
+## v2.4.0
+
+- Enhance: added `Brotli` compression support (using node's zlib).
+- Enhance: updated `Blob` implementation per spec.
+- Fix: set content type automatically for `URLSearchParams`.
+- Fix: `Headers` now reject empty header names.
+- Fix: test cases, as node 12+ no longer accepts invalid header response.
+
+## v2.3.0
+
+- Enhance: added `AbortSignal` support, with README example.
+- Enhance: handle invalid `Location` header during redirect by rejecting them explicitly with `FetchError`.
+- Fix: update `browser.js` to support react-native environment, where `self` isn't available globally.
+
+## v2.2.1
+
+- Fix: `compress` flag shouldn't overwrite existing `Accept-Encoding` header.
+- Fix: multiple `import` rules, where `PassThrough` etc. doesn't have a named export when using node <10 and `--exerimental-modules` flag.
+- Other: Better README.
+
+## v2.2.0
+
+- Enhance: Support all `ArrayBuffer` view types
+- Enhance: Support Web Workers
+- Enhance: Support Node.js' `--experimental-modules` mode; deprecate `.es.js` file
+- Fix: Add `__esModule` property to the exports object
+- Other: Better example in README for writing response to a file
+- Other: More tests for Agent
+
+## v2.1.2
+
+- Fix: allow `Body` methods to work on `ArrayBuffer`-backed `Body` objects
+- Fix: reject promise returned by `Body` methods when the accumulated `Buffer` exceeds the maximum size
+- Fix: support custom `Host` headers with any casing
+- Fix: support importing `fetch()` from TypeScript in `browser.js`
+- Fix: handle the redirect response body properly
+
+## v2.1.1
+
+Fix packaging errors in v2.1.0.
+
+## v2.1.0
+
+- Enhance: allow using ArrayBuffer as the `body` of a `fetch()` or `Request`
+- Fix: store HTTP headers of a `Headers` object internally with the given case, for compatibility with older servers that incorrectly treated header names in a case-sensitive manner
+- Fix: silently ignore invalid HTTP headers
+- Fix: handle HTTP redirect responses without a `Location` header just like non-redirect responses
+- Fix: include bodies when following a redirection when appropriate
+
+## v2.0.0
+
+This is a major release. Check [our upgrade guide](https://github.com/bitinn/node-fetch/blob/master/UPGRADE-GUIDE.md) for an overview on some key differences between v1 and v2.
+
+### General changes
+
+- Major: Node.js 0.10.x and 0.12.x support is dropped
+- Major: `require('node-fetch/lib/response')` etc. is now unsupported; use `require('node-fetch').Response` or ES6 module imports
+- Enhance: start testing on Node.js v4.x, v6.x, v8.x LTS, as well as v9.x stable
+- Enhance: use Rollup to produce a distributed bundle (less memory overhead and faster startup)
+- Enhance: make `Object.prototype.toString()` on Headers, Requests, and Responses return correct class strings
+- Other: rewrite in ES2015 using Babel
+- Other: use Codecov for code coverage tracking
+- Other: update package.json script for npm 5
+- Other: `encoding` module is now optional (alpha.7)
+- Other: expose browser.js through package.json, avoid bundling mishaps (alpha.9)
+- Other: allow TypeScript to `import` node-fetch by exposing default (alpha.9)
+
+### HTTP requests
+
+- Major: overwrite user's `Content-Length` if we can be sure our information is correct (per spec)
+- Fix: errors in a response are caught before the body is accessed
+- Fix: support WHATWG URL objects, created by `whatwg-url` package or `require('url').URL` in Node.js 7+
+
+### Response and Request classes
+
+- Major: `response.text()` no longer attempts to detect encoding, instead always opting for UTF-8 (per spec); use `response.textConverted()` for the v1 behavior
+- Major: make `response.json()` throw error instead of returning an empty object on 204 no-content respose (per spec; reverts behavior changed in v1.6.2)
+- Major: internal methods are no longer exposed
+- Major: throw error when a `GET` or `HEAD` Request is constructed with a non-null body (per spec)
+- Enhance: add `response.arrayBuffer()` (also applies to Requests)
+- Enhance: add experimental `response.blob()` (also applies to Requests)
+- Enhance: `URLSearchParams` is now accepted as a body
+- Enhance: wrap `response.json()` json parsing error as `FetchError`
+- Fix: fix Request and Response with `null` body
+
+### Headers class
+
+- Major: remove `headers.getAll()`; make `get()` return all headers delimited by commas (per spec)
+- Enhance: make Headers iterable
+- Enhance: make Headers constructor accept an array of tuples
+- Enhance: make sure header names and values are valid in HTTP
+- Fix: coerce Headers prototype function parameters to strings, where applicable
+
+### Documentation
+
+- Enhance: more comprehensive API docs
+- Enhance: add a list of default headers in README
+
+
+# 1.x release
+
+## backport releases (v1.7.0 and beyond)
+
+See [changelog on 1.x branch](https://github.com/bitinn/node-fetch/blob/1.x/CHANGELOG.md) for details.
+
+## v1.6.3
+
+- Enhance: error handling document to explain `FetchError` design
+- Fix: support `form-data` 2.x releases (requires `form-data` >= 2.1.0)
+
+## v1.6.2
+
+- Enhance: minor document update
+- Fix: response.json() returns empty object on 204 no-content response instead of throwing a syntax error
+
+## v1.6.1
+
+- Fix: if `res.body` is a non-stream non-formdata object, we will call `body.toString` and send it as a string
+- Fix: `counter` value is incorrectly set to `follow` value when wrapping Request instance
+- Fix: documentation update
+
+## v1.6.0
+
+- Enhance: added `res.buffer()` api for convenience, it returns body as a Node.js buffer
+- Enhance: better old server support by handling raw deflate response
+- Enhance: skip encoding detection for non-HTML/XML response
+- Enhance: minor document update
+- Fix: HEAD request doesn't need decompression, as body is empty
+- Fix: `req.body` now accepts a Node.js buffer
+
+## v1.5.3
+
+- Fix: handle 204 and 304 responses when body is empty but content-encoding is gzip/deflate
+- Fix: allow resolving response and cloned response in any order
+- Fix: avoid setting `content-length` when `form-data` body use streams
+- Fix: send DELETE request with content-length when body is present
+- Fix: allow any url when calling new Request, but still reject non-http(s) url in fetch
+
+## v1.5.2
+
+- Fix: allow node.js core to handle keep-alive connection pool when passing a custom agent
+
+## v1.5.1
+
+- Fix: redirect mode `manual` should work even when there is no redirection or broken redirection
+
+## v1.5.0
+
+- Enhance: rejected promise now use custom `Error` (thx to @pekeler)
+- Enhance: `FetchError` contains `err.type` and `err.code`, allows for better error handling (thx to @pekeler)
+- Enhance: basic support for redirect mode `manual` and `error`, allows for location header extraction (thx to @jimmywarting for the initial PR)
+
+## v1.4.1
+
+- Fix: wrapping Request instance with FormData body again should preserve the body as-is
+
+## v1.4.0
+
+- Enhance: Request and Response now have `clone` method (thx to @kirill-konshin for the initial PR)
+- Enhance: Request and Response now have proper string and buffer body support (thx to @kirill-konshin)
+- Enhance: Body constructor has been refactored out (thx to @kirill-konshin)
+- Enhance: Headers now has `forEach` method (thx to @tricoder42)
+- Enhance: back to 100% code coverage
+- Fix: better form-data support (thx to @item4)
+- Fix: better character encoding detection under chunked encoding (thx to @dsuket for the initial PR)
+
+## v1.3.3
+
+- Fix: make sure `Content-Length` header is set when body is string for POST/PUT/PATCH requests
+- Fix: handle body stream error, for cases such as incorrect `Content-Encoding` header
+- Fix: when following certain redirects, use `GET` on subsequent request per Fetch Spec
+- Fix: `Request` and `Response` constructors now parse headers input using `Headers`
+
+## v1.3.2
+
+- Enhance: allow auto detect of form-data input (no `FormData` spec on node.js, this is form-data specific feature)
+
+## v1.3.1
+
+- Enhance: allow custom host header to be set (server-side only feature, as it's a forbidden header on client-side)
+
+## v1.3.0
+
+- Enhance: now `fetch.Request` is exposed as well
+
+## v1.2.1
+
+- Enhance: `Headers` now normalized `Number` value to `String`, prevent common mistakes
+
+## v1.2.0
+
+- Enhance: now fetch.Headers and fetch.Response are exposed, making testing easier
+
+## v1.1.2
+
+- Fix: `Headers` should only support `String` and `Array` properties, and ignore others
+
+## v1.1.1
+
+- Enhance: now req.headers accept both plain object and `Headers` instance
+
+## v1.1.0
+
+- Enhance: timeout now also applies to response body (in case of slow response)
+- Fix: timeout is now cleared properly when fetch is done/has failed
+
+## v1.0.6
+
+- Fix: less greedy content-type charset matching
+
+## v1.0.5
+
+- Fix: when `follow = 0`, fetch should not follow redirect
+- Enhance: update tests for better coverage
+- Enhance: code formatting
+- Enhance: clean up doc
+
+## v1.0.4
+
+- Enhance: test iojs support
+- Enhance: timeout attached to socket event only fire once per redirect
+
+## v1.0.3
+
+- Fix: response size limit should reject large chunk
+- Enhance: added character encoding detection for xml, such as rss/atom feed (encoding in DTD)
+
+## v1.0.2
+
+- Fix: added res.ok per spec change
+
+## v1.0.0
+
+- Enhance: better test coverage and doc
+
+
+# 0.x release
+
+## v0.1
+
+- Major: initial public release
diff --git a/deps/node-fetch/LICENSE.md b/deps/node-fetch/LICENSE.md
new file mode 100644
index 00000000000000..660ffecb58b02f
--- /dev/null
+++ b/deps/node-fetch/LICENSE.md
@@ -0,0 +1,22 @@
+The MIT License (MIT)
+
+Copyright (c) 2016 David Frank
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+
diff --git a/deps/node-fetch/README.md b/deps/node-fetch/README.md
new file mode 100644
index 00000000000000..cb19901203ecaf
--- /dev/null
+++ b/deps/node-fetch/README.md
@@ -0,0 +1,583 @@
+node-fetch
+==========
+
+[![npm version][npm-image]][npm-url]
+[![build status][travis-image]][travis-url]
+[![coverage status][codecov-image]][codecov-url]
+[![install size][install-size-image]][install-size-url]
+
+A light-weight module that brings `window.fetch` to Node.js
+
+(We are looking for [v2 maintainers and collaborators](https://github.com/bitinn/node-fetch/issues/567))
+
+<!-- TOC -->
+
+- [Motivation](#motivation)
+- [Features](#features)
+- [Difference from client-side fetch](#difference-from-client-side-fetch)
+- [Installation](#installation)
+- [Loading and configuring the module](#loading-and-configuring-the-module)
+- [Common Usage](#common-usage)
+    - [Plain text or HTML](#plain-text-or-html)
+    - [JSON](#json)
+    - [Simple Post](#simple-post)
+    - [Post with JSON](#post-with-json)
+    - [Post with form parameters](#post-with-form-parameters)
+    - [Handling exceptions](#handling-exceptions)
+    - [Handling client and server errors](#handling-client-and-server-errors)
+- [Advanced Usage](#advanced-usage)
+    - [Streams](#streams)
+    - [Buffer](#buffer)
+    - [Accessing Headers and other Meta data](#accessing-headers-and-other-meta-data)
+    - [Extract Set-Cookie Header](#extract-set-cookie-header)
+    - [Post data using a file stream](#post-data-using-a-file-stream)
+    - [Post with form-data (detect multipart)](#post-with-form-data-detect-multipart)
+    - [Request cancellation with AbortSignal](#request-cancellation-with-abortsignal)
+- [API](#api)
+    - [fetch(url[, options])](#fetchurl-options)
+    - [Options](#options)
+    - [Class: Request](#class-request)
+    - [Class: Response](#class-response)
+    - [Class: Headers](#class-headers)
+    - [Interface: Body](#interface-body)
+    - [Class: FetchError](#class-fetcherror)
+- [License](#license)
+- [Acknowledgement](#acknowledgement)
+
+<!-- /TOC -->
+
+## Motivation
+
+Instead of implementing `XMLHttpRequest` in Node.js to run browser-specific [Fetch polyfill](https://github.com/github/fetch), why not go from native `http` to `fetch` API directly? Hence `node-fetch`, minimal code for a `window.fetch` compatible API on Node.js runtime.
+
+See Matt Andrews' [isomorphic-fetch](https://github.com/matthew-andrews/isomorphic-fetch) or Leonardo Quixada's [cross-fetch](https://github.com/lquixada/cross-fetch) for isomorphic usage (exports `node-fetch` for server-side, `whatwg-fetch` for client-side).
+
+## Features
+
+- Stay consistent with `window.fetch` API.
+- Make conscious trade-off when following [WHATWG fetch spec][whatwg-fetch] and [stream spec](https://streams.spec.whatwg.org/) implementation details, document known differences.
+- Use native promise, but allow substituting it with [insert your favorite promise library].
+- Use native Node streams for body, on both request and response.
+- Decode content encoding (gzip/deflate) properly, and convert string output (such as `res.text()` and `res.json()`) to UTF-8 automatically.
+- Useful extensions such as timeout, redirect limit, response size limit, [explicit errors](ERROR-HANDLING.md) for troubleshooting.
+
+## Difference from client-side fetch
+
+- See [Known Differences](LIMITS.md) for details.
+- If you happen to use a missing feature that `window.fetch` offers, feel free to open an issue.
+- Pull requests are welcomed too!
+
+## Installation
+
+Current stable release (`2.x`)
+
+```sh
+$ npm install node-fetch --save
+```
+
+## Loading and configuring the module
+We suggest you load the module via `require`, pending the stabalizing of es modules in node:
+```js
+const fetch = require('node-fetch');
+```
+
+If you are using a Promise library other than native, set it through fetch.Promise:
+```js
+const Bluebird = require('bluebird');
+
+fetch.Promise = Bluebird;
+```
+
+## Common Usage
+
+NOTE: The documentation below is up-to-date with `2.x` releases, [see `1.x` readme](https://github.com/bitinn/node-fetch/blob/1.x/README.md), [changelog](https://github.com/bitinn/node-fetch/blob/1.x/CHANGELOG.md) and [2.x upgrade guide](UPGRADE-GUIDE.md) for the differences.
+
+#### Plain text or HTML
+```js
+fetch('https://github.com/')
+    .then(res => res.text())
+    .then(body => console.log(body));
+```
+
+#### JSON
+
+```js
+
+fetch('https://api.github.com/users/github')
+    .then(res => res.json())
+    .then(json => console.log(json));
+```
+
+#### Simple Post
+```js
+fetch('https://httpbin.org/post', { method: 'POST', body: 'a=1' })
+    .then(res => res.json()) // expecting a json response
+    .then(json => console.log(json));
+```
+
+#### Post with JSON
+
+```js
+const body = { a: 1 };
+
+fetch('https://httpbin.org/post', {
+        method: 'post',
+        body:    JSON.stringify(body),
+        headers: { 'Content-Type': 'application/json' },
+    })
+    .then(res => res.json())
+    .then(json => console.log(json));
+```
+
+#### Post with form parameters
+`URLSearchParams` is available in Node.js as of v7.5.0. See [official documentation](https://nodejs.org/api/url.html#url_class_urlsearchparams) for more usage methods.
+
+NOTE: The `Content-Type` header is only set automatically to `x-www-form-urlencoded` when an instance of `URLSearchParams` is given as such:
+
+```js
+const { URLSearchParams } = require('url');
+
+const params = new URLSearchParams();
+params.append('a', 1);
+
+fetch('https://httpbin.org/post', { method: 'POST', body: params })
+    .then(res => res.json())
+    .then(json => console.log(json));
+```
+
+#### Handling exceptions
+NOTE: 3xx-5xx responses are *NOT* exceptions, and should be handled in `then()`, see the next section.
+
+Adding a catch to the fetch promise chain will catch *all* exceptions, such as errors originating from node core libraries, like network errors, and operational errors which are instances of FetchError. See the [error handling document](ERROR-HANDLING.md)  for more details.
+
+```js
+fetch('https://domain.invalid/')
+    .catch(err => console.error(err));
+```
+
+#### Handling client and server errors
+It is common to create a helper function to check that the response contains no client (4xx) or server (5xx) error responses:
+
+```js
+function checkStatus(res) {
+    if (res.ok) { // res.status >= 200 && res.status < 300
+        return res;
+    } else {
+        throw MyCustomError(res.statusText);
+    }
+}
+
+fetch('https://httpbin.org/status/400')
+    .then(checkStatus)
+    .then(res => console.log('will not get here...'))
+```
+
+## Advanced Usage
+
+#### Streams
+The "Node.js way" is to use streams when possible:
+
+```js
+fetch('https://assets-cdn.github.com/images/modules/logos_page/Octocat.png')
+    .then(res => {
+        const dest = fs.createWriteStream('./octocat.png');
+        res.body.pipe(dest);
+    });
+```
+
+#### Buffer
+If you prefer to cache binary data in full, use buffer(). (NOTE: buffer() is a `node-fetch` only API)
+
+```js
+const fileType = require('file-type');
+
+fetch('https://assets-cdn.github.com/images/modules/logos_page/Octocat.png')
+    .then(res => res.buffer())
+    .then(buffer => fileType(buffer))
+    .then(type => { /* ... */ });
+```
+
+#### Accessing Headers and other Meta data
+```js
+fetch('https://github.com/')
+    .then(res => {
+        console.log(res.ok);
+        console.log(res.status);
+        console.log(res.statusText);
+        console.log(res.headers.raw());
+        console.log(res.headers.get('content-type'));
+    });
+```
+
+#### Extract Set-Cookie Header
+
+Unlike browsers, you can access raw `Set-Cookie` headers manually using `Headers.raw()`, this is a `node-fetch` only API.
+
+```js
+fetch(url).then(res => {
+    // returns an array of values, instead of a string of comma-separated values
+    console.log(res.headers.raw()['set-cookie']);
+});
+```
+
+#### Post data using a file stream
+
+```js
+const { createReadStream } = require('fs');
+
+const stream = createReadStream('input.txt');
+
+fetch('https://httpbin.org/post', { method: 'POST', body: stream })
+    .then(res => res.json())
+    .then(json => console.log(json));
+```
+
+#### Post with form-data (detect multipart)
+
+```js
+const FormData = require('form-data');
+
+const form = new FormData();
+form.append('a', 1);
+
+fetch('https://httpbin.org/post', { method: 'POST', body: form })
+    .then(res => res.json())
+    .then(json => console.log(json));
+
+// OR, using custom headers
+// NOTE: getHeaders() is non-standard API
+
+const form = new FormData();
+form.append('a', 1);
+
+const options = {
+    method: 'POST',
+    body: form,
+    headers: form.getHeaders()
+}
+
+fetch('https://httpbin.org/post', options)
+    .then(res => res.json())
+    .then(json => console.log(json));
+```
+
+#### Request cancellation with AbortSignal
+
+> NOTE: You may only cancel streamed requests on Node >= v8.0.0
+
+You may cancel requests with `AbortController`. A suggested implementation is [`abort-controller`](https://www.npmjs.com/package/abort-controller).
+
+An example of timing out a request after 150ms could be achieved as follows:
+
+```js
+import AbortController from 'abort-controller';
+
+const controller = new AbortController();
+const timeout = setTimeout(
+  () => { controller.abort(); },
+  150,
+);
+
+fetch(url, { signal: controller.signal })
+  .then(res => res.json())
+  .then(
+    data => {
+      useData(data)
+    },
+    err => {
+      if (err.name === 'AbortError') {
+        // request was aborted
+      }
+    },
+  )
+  .finally(() => {
+    clearTimeout(timeout);
+  });
+```
+
+See [test cases](https://github.com/bitinn/node-fetch/blob/master/test/test.js) for more examples.
+
+
+## API
+
+### fetch(url[, options])
+
+- `url` A string representing the URL for fetching
+- `options` [Options](#fetch-options) for the HTTP(S) request
+- Returns: <code>Promise&lt;[Response](#class-response)&gt;</code>
+
+Perform an HTTP(S) fetch.
+
+`url` should be an absolute url, such as `https://example.com/`. A path-relative URL (`/file/under/root`) or protocol-relative URL (`//can-be-http-or-https.com/`) will result in a rejected promise.
+
+<a id="fetch-options"></a>
+### Options
+
+The default values are shown after each option key.
+
+```js
+{
+    // These properties are part of the Fetch Standard
+    method: 'GET',
+    headers: {},        // request headers. format is the identical to that accepted by the Headers constructor (see below)
+    body: null,         // request body. can be null, a string, a Buffer, a Blob, or a Node.js Readable stream
+    redirect: 'follow', // set to `manual` to extract redirect headers, `error` to reject redirect
+    signal: null,       // pass an instance of AbortSignal to optionally abort requests
+
+    // The following properties are node-fetch extensions
+    follow: 20,         // maximum redirect count. 0 to not follow redirect
+    timeout: 0,         // req/res timeout in ms, it resets on redirect. 0 to disable (OS limit applies). Signal is recommended instead.
+    compress: true,     // support gzip/deflate content encoding. false to disable
+    size: 0,            // maximum response body size in bytes. 0 to disable
+    agent: null         // http(s).Agent instance or function that returns an instance (see below)
+}
+```
+
+##### Default Headers
+
+If no values are set, the following request headers will be sent automatically:
+
+Header              | Value
+------------------- | --------------------------------------------------------
+`Accept-Encoding`   | `gzip,deflate` _(when `options.compress === true`)_
+`Accept`            | `*/*`
+`Connection`        | `close` _(when no `options.agent` is present)_
+`Content-Length`    | _(automatically calculated, if possible)_
+`Transfer-Encoding` | `chunked` _(when `req.body` is a stream)_
+`User-Agent`        | `node-fetch/1.0 (+https://github.com/bitinn/node-fetch)`
+
+Note: when `body` is a `Stream`, `Content-Length` is not set automatically.
+
+##### Custom Agent
+
+The `agent` option allows you to specify networking related options that's out of the scope of Fetch. Including and not limit to:
+
+- Support self-signed certificate
+- Use only IPv4 or IPv6
+- Custom DNS Lookup
+
+See [`http.Agent`](https://nodejs.org/api/http.html#http_new_agent_options) for more information.
+
+In addition, `agent` option accepts a function that returns http(s).Agent instance given current [URL](https://nodejs.org/api/url.html), this is useful during a redirection chain across HTTP and HTTPS protocol.
+
+```js
+const httpAgent = new http.Agent({
+    keepAlive: true
+});
+const httpsAgent = new https.Agent({
+    keepAlive: true
+});
+
+const options = {
+    agent: function (_parsedURL) {
+        if (_parsedURL.protocol == 'http:') {
+            return httpAgent;
+        } else {
+            return httpsAgent;
+        }
+    }
+}
+```
+
+<a id="class-request"></a>
+### Class: Request
+
+An HTTP(S) request containing information about URL, method, headers, and the body. This class implements the [Body](#iface-body) interface.
+
+Due to the nature of Node.js, the following properties are not implemented at this moment:
+
+- `type`
+- `destination`
+- `referrer`
+- `referrerPolicy`
+- `mode`
+- `credentials`
+- `cache`
+- `integrity`
+- `keepalive`
+
+The following node-fetch extension properties are provided:
+
+- `follow`
+- `compress`
+- `counter`
+- `agent`
+
+See [options](#fetch-options) for exact meaning of these extensions.
+
+#### new Request(input[, options])
+
+<small>*(spec-compliant)*</small>
+
+- `input` A string representing a URL, or another `Request` (which will be cloned)
+- `options` [Options][#fetch-options] for the HTTP(S) request
+
+Constructs a new `Request` object. The constructor is identical to that in the [browser](https://developer.mozilla.org/en-US/docs/Web/API/Request/Request).
+
+In most cases, directly `fetch(url, options)` is simpler than creating a `Request` object.
+
+<a id="class-response"></a>
+### Class: Response
+
+An HTTP(S) response. This class implements the [Body](#iface-body) interface.
+
+The following properties are not implemented in node-fetch at this moment:
+
+- `Response.error()`
+- `Response.redirect()`
+- `type`
+- `trailer`
+
+#### new Response([body[, options]])
+
+<small>*(spec-compliant)*</small>
+
+- `body` A string or [Readable stream][node-readable]
+- `options` A [`ResponseInit`][response-init] options dictionary
+
+Constructs a new `Response` object. The constructor is identical to that in the [browser](https://developer.mozilla.org/en-US/docs/Web/API/Response/Response).
+
+Because Node.js does not implement service workers (for which this class was designed), one rarely has to construct a `Response` directly.
+
+#### response.ok
+
+<small>*(spec-compliant)*</small>
+
+Convenience property representing if the request ended normally. Will evaluate to true if the response status was greater than or equal to 200 but smaller than 300.
+
+#### response.redirected
+
+<small>*(spec-compliant)*</small>
+
+Convenience property representing if the request has been redirected at least once. Will evaluate to true if the internal redirect counter is greater than 0.
+
+<a id="class-headers"></a>
+### Class: Headers
+
+This class allows manipulating and iterating over a set of HTTP headers. All methods specified in the [Fetch Standard][whatwg-fetch] are implemented.
+
+#### new Headers([init])
+
+<small>*(spec-compliant)*</small>
+
+- `init` Optional argument to pre-fill the `Headers` object
+
+Construct a new `Headers` object. `init` can be either `null`, a `Headers` object, an key-value map object, or any iterable object.
+
+```js
+// Example adapted from https://fetch.spec.whatwg.org/#example-headers-class
+
+const meta = {
+  'Content-Type': 'text/xml',
+  'Breaking-Bad': '<3'
+};
+const headers = new Headers(meta);
+
+// The above is equivalent to
+const meta = [
+  [ 'Content-Type', 'text/xml' ],
+  [ 'Breaking-Bad', '<3' ]
+];
+const headers = new Headers(meta);
+
+// You can in fact use any iterable objects, like a Map or even another Headers
+const meta = new Map();
+meta.set('Content-Type', 'text/xml');
+meta.set('Breaking-Bad', '<3');
+const headers = new Headers(meta);
+const copyOfHeaders = new Headers(headers);
+```
+
+<a id="iface-body"></a>
+### Interface: Body
+
+`Body` is an abstract interface with methods that are applicable to both `Request` and `Response` classes.
+
+The following methods are not yet implemented in node-fetch at this moment:
+
+- `formData()`
+
+#### body.body
+
+<small>*(deviation from spec)*</small>
+
+* Node.js [`Readable` stream][node-readable]
+
+The data encapsulated in the `Body` object. Note that while the [Fetch Standard][whatwg-fetch] requires the property to always be a WHATWG `ReadableStream`, in node-fetch it is a Node.js [`Readable` stream][node-readable].
+
+#### body.bodyUsed
+
+<small>*(spec-compliant)*</small>
+
+* `Boolean`
+
+A boolean property for if this body has been consumed. Per spec, a consumed body cannot be used again.
+
+#### body.arrayBuffer()
+#### body.blob()
+#### body.json()
+#### body.text()
+
+<small>*(spec-compliant)*</small>
+
+* Returns: <code>Promise</code>
+
+Consume the body and return a promise that will resolve to one of these formats.
+
+#### body.buffer()
+
+<small>*(node-fetch extension)*</small>
+
+* Returns: <code>Promise&lt;Buffer&gt;</code>
+
+Consume the body and return a promise that will resolve to a Buffer.
+
+#### body.textConverted()
+
+<small>*(node-fetch extension)*</small>
+
+* Returns: <code>Promise&lt;String&gt;</code>
+
+Identical to `body.text()`, except instead of always converting to UTF-8, encoding sniffing will be performed and text converted to UTF-8, if possible.
+
+(This API requires an optional dependency on npm package [encoding](https://www.npmjs.com/package/encoding), which you need to install manually. `webpack` users may see [a warning message](https://github.com/bitinn/node-fetch/issues/412#issuecomment-379007792) due to this optional dependency.)
+
+<a id="class-fetcherror"></a>
+### Class: FetchError
+
+<small>*(node-fetch extension)*</small>
+
+An operational error in the fetching process. See [ERROR-HANDLING.md][] for more info.
+
+<a id="class-aborterror"></a>
+### Class: AbortError
+
+<small>*(node-fetch extension)*</small>
+
+An Error thrown when the request is aborted in response to an `AbortSignal`'s `abort` event. It has a `name` property of `AbortError`. See [ERROR-HANDLING.MD][] for more info.
+
+## Acknowledgement
+
+Thanks to [github/fetch](https://github.com/github/fetch) for providing a solid implementation reference.
+
+`node-fetch` v1 was maintained by [@bitinn](https://github.com/bitinn); v2 was maintained by [@TimothyGu](https://github.com/timothygu), [@bitinn](https://github.com/bitinn) and [@jimmywarting](https://github.com/jimmywarting); v2 readme is written by [@jkantr](https://github.com/jkantr).
+
+## License
+
+MIT
+
+[npm-image]: https://flat.badgen.net/npm/v/node-fetch
+[npm-url]: https://www.npmjs.com/package/node-fetch
+[travis-image]: https://flat.badgen.net/travis/bitinn/node-fetch
+[travis-url]: https://travis-ci.org/bitinn/node-fetch
+[codecov-image]: https://flat.badgen.net/codecov/c/github/bitinn/node-fetch/master
+[codecov-url]: https://codecov.io/gh/bitinn/node-fetch
+[install-size-image]: https://flat.badgen.net/packagephobia/install/node-fetch
+[install-size-url]: https://packagephobia.now.sh/result?p=node-fetch
+[whatwg-fetch]: https://fetch.spec.whatwg.org/
+[response-init]: https://fetch.spec.whatwg.org/#responseinit
+[node-readable]: https://nodejs.org/api/stream.html#stream_readable_streams
+[mdn-headers]: https://developer.mozilla.org/en-US/docs/Web/API/Headers
+[LIMITS.md]: https://github.com/bitinn/node-fetch/blob/master/LIMITS.md
+[ERROR-HANDLING.md]: https://github.com/bitinn/node-fetch/blob/master/ERROR-HANDLING.md
+[UPGRADE-GUIDE.md]: https://github.com/bitinn/node-fetch/blob/master/UPGRADE-GUIDE.md
diff --git a/deps/node-fetch/browser.js b/deps/node-fetch/browser.js
new file mode 100644
index 00000000000000..0ad5de004c43ec
--- /dev/null
+++ b/deps/node-fetch/browser.js
@@ -0,0 +1,23 @@
+"use strict";
+
+// ref: https://github.com/tc39/proposal-global
+var getGlobal = function () {
+	// the only reliable means to get the global object is
+	// `Function('return this')()`
+	// However, this causes CSP violations in Chrome apps.
+	if (typeof self !== 'undefined') { return self; }
+	if (typeof window !== 'undefined') { return window; }
+	if (typeof global !== 'undefined') { return global; }
+	throw new Error('unable to locate global object');
+}
+
+var global = getGlobal();
+
+module.exports = exports = global.fetch;
+
+// Needed for TypeScript and Webpack.
+exports.default = global.fetch.bind(global);
+
+exports.Headers = global.Headers;
+exports.Request = global.Request;
+exports.Response = global.Response;
\ No newline at end of file
diff --git a/deps/node-fetch/lib/index.es.js b/deps/node-fetch/lib/index.es.js
new file mode 100644
index 00000000000000..37d022c91f8b89
--- /dev/null
+++ b/deps/node-fetch/lib/index.es.js
@@ -0,0 +1,1633 @@
+process.emitWarning("The .es.js file is deprecated. Use .mjs instead.");
+
+import Stream from 'stream';
+import http from 'http';
+import Url from 'url';
+import https from 'https';
+import zlib from 'zlib';
+
+// Based on https://github.com/tmpvar/jsdom/blob/aa85b2abf07766ff7bf5c1f6daafb3726f2f2db5/lib/jsdom/living/blob.js
+
+// fix for "Readable" isn't a named export issue
+const Readable = Stream.Readable;
+
+const BUFFER = Symbol('buffer');
+const TYPE = Symbol('type');
+
+class Blob {
+	constructor() {
+		this[TYPE] = '';
+
+		const blobParts = arguments[0];
+		const options = arguments[1];
+
+		const buffers = [];
+		let size = 0;
+
+		if (blobParts) {
+			const a = blobParts;
+			const length = Number(a.length);
+			for (let i = 0; i < length; i++) {
+				const element = a[i];
+				let buffer;
+				if (element instanceof Buffer) {
+					buffer = element;
+				} else if (ArrayBuffer.isView(element)) {
+					buffer = Buffer.from(element.buffer, element.byteOffset, element.byteLength);
+				} else if (element instanceof ArrayBuffer) {
+					buffer = Buffer.from(element);
+				} else if (element instanceof Blob) {
+					buffer = element[BUFFER];
+				} else {
+					buffer = Buffer.from(typeof element === 'string' ? element : String(element));
+				}
+				size += buffer.length;
+				buffers.push(buffer);
+			}
+		}
+
+		this[BUFFER] = Buffer.concat(buffers);
+
+		let type = options && options.type !== undefined && String(options.type).toLowerCase();
+		if (type && !/[^\u0020-\u007E]/.test(type)) {
+			this[TYPE] = type;
+		}
+	}
+	get size() {
+		return this[BUFFER].length;
+	}
+	get type() {
+		return this[TYPE];
+	}
+	text() {
+		return Promise.resolve(this[BUFFER].toString());
+	}
+	arrayBuffer() {
+		const buf = this[BUFFER];
+		const ab = buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength);
+		return Promise.resolve(ab);
+	}
+	stream() {
+		const readable = new Readable();
+		readable._read = function () {};
+		readable.push(this[BUFFER]);
+		readable.push(null);
+		return readable;
+	}
+	toString() {
+		return '[object Blob]';
+	}
+	slice() {
+		const size = this.size;
+
+		const start = arguments[0];
+		const end = arguments[1];
+		let relativeStart, relativeEnd;
+		if (start === undefined) {
+			relativeStart = 0;
+		} else if (start < 0) {
+			relativeStart = Math.max(size + start, 0);
+		} else {
+			relativeStart = Math.min(start, size);
+		}
+		if (end === undefined) {
+			relativeEnd = size;
+		} else if (end < 0) {
+			relativeEnd = Math.max(size + end, 0);
+		} else {
+			relativeEnd = Math.min(end, size);
+		}
+		const span = Math.max(relativeEnd - relativeStart, 0);
+
+		const buffer = this[BUFFER];
+		const slicedBuffer = buffer.slice(relativeStart, relativeStart + span);
+		const blob = new Blob([], { type: arguments[2] });
+		blob[BUFFER] = slicedBuffer;
+		return blob;
+	}
+}
+
+Object.defineProperties(Blob.prototype, {
+	size: { enumerable: true },
+	type: { enumerable: true },
+	slice: { enumerable: true }
+});
+
+Object.defineProperty(Blob.prototype, Symbol.toStringTag, {
+	value: 'Blob',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+/**
+ * fetch-error.js
+ *
+ * FetchError interface for operational errors
+ */
+
+/**
+ * Create FetchError instance
+ *
+ * @param   String      message      Error message for human
+ * @param   String      type         Error type for machine
+ * @param   String      systemError  For Node.js system error
+ * @return  FetchError
+ */
+function FetchError(message, type, systemError) {
+  Error.call(this, message);
+
+  this.message = message;
+  this.type = type;
+
+  // when err.type is `system`, err.code contains system error code
+  if (systemError) {
+    this.code = this.errno = systemError.code;
+  }
+
+  // hide custom error implementation details from end-users
+  Error.captureStackTrace(this, this.constructor);
+}
+
+FetchError.prototype = Object.create(Error.prototype);
+FetchError.prototype.constructor = FetchError;
+FetchError.prototype.name = 'FetchError';
+
+let convert;
+try {
+	convert = require('encoding').convert;
+} catch (e) {}
+
+const INTERNALS = Symbol('Body internals');
+
+// fix an issue where "PassThrough" isn't a named export for node <10
+const PassThrough = Stream.PassThrough;
+
+/**
+ * Body mixin
+ *
+ * Ref: https://fetch.spec.whatwg.org/#body
+ *
+ * @param   Stream  body  Readable stream
+ * @param   Object  opts  Response options
+ * @return  Void
+ */
+function Body(body) {
+	var _this = this;
+
+	var _ref = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {},
+	    _ref$size = _ref.size;
+
+	let size = _ref$size === undefined ? 0 : _ref$size;
+	var _ref$timeout = _ref.timeout;
+	let timeout = _ref$timeout === undefined ? 0 : _ref$timeout;
+
+	if (body == null) {
+		// body is undefined or null
+		body = null;
+	} else if (isURLSearchParams(body)) {
+		// body is a URLSearchParams
+		body = Buffer.from(body.toString());
+	} else if (isBlob(body)) ; else if (Buffer.isBuffer(body)) ; else if (Object.prototype.toString.call(body) === '[object ArrayBuffer]') {
+		// body is ArrayBuffer
+		body = Buffer.from(body);
+	} else if (ArrayBuffer.isView(body)) {
+		// body is ArrayBufferView
+		body = Buffer.from(body.buffer, body.byteOffset, body.byteLength);
+	} else if (body instanceof Stream) ; else {
+		// none of the above
+		// coerce to string then buffer
+		body = Buffer.from(String(body));
+	}
+	this[INTERNALS] = {
+		body,
+		disturbed: false,
+		error: null
+	};
+	this.size = size;
+	this.timeout = timeout;
+
+	if (body instanceof Stream) {
+		body.on('error', function (err) {
+			const error = err.name === 'AbortError' ? err : new FetchError(`Invalid response body while trying to fetch ${_this.url}: ${err.message}`, 'system', err);
+			_this[INTERNALS].error = error;
+		});
+	}
+}
+
+Body.prototype = {
+	get body() {
+		return this[INTERNALS].body;
+	},
+
+	get bodyUsed() {
+		return this[INTERNALS].disturbed;
+	},
+
+	/**
+  * Decode response as ArrayBuffer
+  *
+  * @return  Promise
+  */
+	arrayBuffer() {
+		return consumeBody.call(this).then(function (buf) {
+			return buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength);
+		});
+	},
+
+	/**
+  * Return raw response as Blob
+  *
+  * @return Promise
+  */
+	blob() {
+		let ct = this.headers && this.headers.get('content-type') || '';
+		return consumeBody.call(this).then(function (buf) {
+			return Object.assign(
+			// Prevent copying
+			new Blob([], {
+				type: ct.toLowerCase()
+			}), {
+				[BUFFER]: buf
+			});
+		});
+	},
+
+	/**
+  * Decode response as json
+  *
+  * @return  Promise
+  */
+	json() {
+		var _this2 = this;
+
+		return consumeBody.call(this).then(function (buffer) {
+			try {
+				return JSON.parse(buffer.toString());
+			} catch (err) {
+				return Body.Promise.reject(new FetchError(`invalid json response body at ${_this2.url} reason: ${err.message}`, 'invalid-json'));
+			}
+		});
+	},
+
+	/**
+  * Decode response as text
+  *
+  * @return  Promise
+  */
+	text() {
+		return consumeBody.call(this).then(function (buffer) {
+			return buffer.toString();
+		});
+	},
+
+	/**
+  * Decode response as buffer (non-spec api)
+  *
+  * @return  Promise
+  */
+	buffer() {
+		return consumeBody.call(this);
+	},
+
+	/**
+  * Decode response as text, while automatically detecting the encoding and
+  * trying to decode to UTF-8 (non-spec api)
+  *
+  * @return  Promise
+  */
+	textConverted() {
+		var _this3 = this;
+
+		return consumeBody.call(this).then(function (buffer) {
+			return convertBody(buffer, _this3.headers);
+		});
+	}
+};
+
+// In browsers, all properties are enumerable.
+Object.defineProperties(Body.prototype, {
+	body: { enumerable: true },
+	bodyUsed: { enumerable: true },
+	arrayBuffer: { enumerable: true },
+	blob: { enumerable: true },
+	json: { enumerable: true },
+	text: { enumerable: true }
+});
+
+Body.mixIn = function (proto) {
+	for (const name of Object.getOwnPropertyNames(Body.prototype)) {
+		// istanbul ignore else: future proof
+		if (!(name in proto)) {
+			const desc = Object.getOwnPropertyDescriptor(Body.prototype, name);
+			Object.defineProperty(proto, name, desc);
+		}
+	}
+};
+
+/**
+ * Consume and convert an entire Body to a Buffer.
+ *
+ * Ref: https://fetch.spec.whatwg.org/#concept-body-consume-body
+ *
+ * @return  Promise
+ */
+function consumeBody() {
+	var _this4 = this;
+
+	if (this[INTERNALS].disturbed) {
+		return Body.Promise.reject(new TypeError(`body used already for: ${this.url}`));
+	}
+
+	this[INTERNALS].disturbed = true;
+
+	if (this[INTERNALS].error) {
+		return Body.Promise.reject(this[INTERNALS].error);
+	}
+
+	let body = this.body;
+
+	// body is null
+	if (body === null) {
+		return Body.Promise.resolve(Buffer.alloc(0));
+	}
+
+	// body is blob
+	if (isBlob(body)) {
+		body = body.stream();
+	}
+
+	// body is buffer
+	if (Buffer.isBuffer(body)) {
+		return Body.Promise.resolve(body);
+	}
+
+	// istanbul ignore if: should never happen
+	if (!(body instanceof Stream)) {
+		return Body.Promise.resolve(Buffer.alloc(0));
+	}
+
+	// body is stream
+	// get ready to actually consume the body
+	let accum = [];
+	let accumBytes = 0;
+	let abort = false;
+
+	return new Body.Promise(function (resolve, reject) {
+		let resTimeout;
+
+		// allow timeout on slow response body
+		if (_this4.timeout) {
+			resTimeout = setTimeout(function () {
+				abort = true;
+				reject(new FetchError(`Response timeout while trying to fetch ${_this4.url} (over ${_this4.timeout}ms)`, 'body-timeout'));
+			}, _this4.timeout);
+		}
+
+		// handle stream errors
+		body.on('error', function (err) {
+			if (err.name === 'AbortError') {
+				// if the request was aborted, reject with this Error
+				abort = true;
+				reject(err);
+			} else {
+				// other errors, such as incorrect content-encoding
+				reject(new FetchError(`Invalid response body while trying to fetch ${_this4.url}: ${err.message}`, 'system', err));
+			}
+		});
+
+		body.on('data', function (chunk) {
+			if (abort || chunk === null) {
+				return;
+			}
+
+			if (_this4.size && accumBytes + chunk.length > _this4.size) {
+				abort = true;
+				reject(new FetchError(`content size at ${_this4.url} over limit: ${_this4.size}`, 'max-size'));
+				return;
+			}
+
+			accumBytes += chunk.length;
+			accum.push(chunk);
+		});
+
+		body.on('end', function () {
+			if (abort) {
+				return;
+			}
+
+			clearTimeout(resTimeout);
+
+			try {
+				resolve(Buffer.concat(accum, accumBytes));
+			} catch (err) {
+				// handle streams that have accumulated too much data (issue #414)
+				reject(new FetchError(`Could not create Buffer from response body for ${_this4.url}: ${err.message}`, 'system', err));
+			}
+		});
+	});
+}
+
+/**
+ * Detect buffer encoding and convert to target encoding
+ * ref: http://www.w3.org/TR/2011/WD-html5-20110113/parsing.html#determining-the-character-encoding
+ *
+ * @param   Buffer  buffer    Incoming buffer
+ * @param   String  encoding  Target encoding
+ * @return  String
+ */
+function convertBody(buffer, headers) {
+	if (typeof convert !== 'function') {
+		throw new Error('The package `encoding` must be installed to use the textConverted() function');
+	}
+
+	const ct = headers.get('content-type');
+	let charset = 'utf-8';
+	let res, str;
+
+	// header
+	if (ct) {
+		res = /charset=([^;]*)/i.exec(ct);
+	}
+
+	// no charset in content type, peek at response body for at most 1024 bytes
+	str = buffer.slice(0, 1024).toString();
+
+	// html5
+	if (!res && str) {
+		res = /<meta.+?charset=(['"])(.+?)\1/i.exec(str);
+	}
+
+	// html4
+	if (!res && str) {
+		res = /<meta[\s]+?http-equiv=(['"])content-type\1[\s]+?content=(['"])(.+?)\2/i.exec(str);
+
+		if (res) {
+			res = /charset=(.*)/i.exec(res.pop());
+		}
+	}
+
+	// xml
+	if (!res && str) {
+		res = /<\?xml.+?encoding=(['"])(.+?)\1/i.exec(str);
+	}
+
+	// found charset
+	if (res) {
+		charset = res.pop();
+
+		// prevent decode issues when sites use incorrect encoding
+		// ref: https://hsivonen.fi/encoding-menu/
+		if (charset === 'gb2312' || charset === 'gbk') {
+			charset = 'gb18030';
+		}
+	}
+
+	// turn raw buffers into a single utf-8 buffer
+	return convert(buffer, 'UTF-8', charset).toString();
+}
+
+/**
+ * Detect a URLSearchParams object
+ * ref: https://github.com/bitinn/node-fetch/issues/296#issuecomment-307598143
+ *
+ * @param   Object  obj     Object to detect by type or brand
+ * @return  String
+ */
+function isURLSearchParams(obj) {
+	// Duck-typing as a necessary condition.
+	if (typeof obj !== 'object' || typeof obj.append !== 'function' || typeof obj.delete !== 'function' || typeof obj.get !== 'function' || typeof obj.getAll !== 'function' || typeof obj.has !== 'function' || typeof obj.set !== 'function') {
+		return false;
+	}
+
+	// Brand-checking and more duck-typing as optional condition.
+	return obj.constructor.name === 'URLSearchParams' || Object.prototype.toString.call(obj) === '[object URLSearchParams]' || typeof obj.sort === 'function';
+}
+
+/**
+ * Check if `obj` is a W3C `Blob` object (which `File` inherits from)
+ * @param  {*} obj
+ * @return {boolean}
+ */
+function isBlob(obj) {
+	return typeof obj === 'object' && typeof obj.arrayBuffer === 'function' && typeof obj.type === 'string' && typeof obj.stream === 'function' && typeof obj.constructor === 'function' && typeof obj.constructor.name === 'string' && /^(Blob|File)$/.test(obj.constructor.name) && /^(Blob|File)$/.test(obj[Symbol.toStringTag]);
+}
+
+/**
+ * Clone body given Res/Req instance
+ *
+ * @param   Mixed  instance  Response or Request instance
+ * @return  Mixed
+ */
+function clone(instance) {
+	let p1, p2;
+	let body = instance.body;
+
+	// don't allow cloning a used body
+	if (instance.bodyUsed) {
+		throw new Error('cannot clone body after it is used');
+	}
+
+	// check that body is a stream and not form-data object
+	// note: we can't clone the form-data object without having it as a dependency
+	if (body instanceof Stream && typeof body.getBoundary !== 'function') {
+		// tee instance body
+		p1 = new PassThrough();
+		p2 = new PassThrough();
+		body.pipe(p1);
+		body.pipe(p2);
+		// set instance body to teed body and return the other teed body
+		instance[INTERNALS].body = p1;
+		body = p2;
+	}
+
+	return body;
+}
+
+/**
+ * Performs the operation "extract a `Content-Type` value from |object|" as
+ * specified in the specification:
+ * https://fetch.spec.whatwg.org/#concept-bodyinit-extract
+ *
+ * This function assumes that instance.body is present.
+ *
+ * @param   Mixed  instance  Any options.body input
+ */
+function extractContentType(body) {
+	if (body === null) {
+		// body is null
+		return null;
+	} else if (typeof body === 'string') {
+		// body is string
+		return 'text/plain;charset=UTF-8';
+	} else if (isURLSearchParams(body)) {
+		// body is a URLSearchParams
+		return 'application/x-www-form-urlencoded;charset=UTF-8';
+	} else if (isBlob(body)) {
+		// body is blob
+		return body.type || null;
+	} else if (Buffer.isBuffer(body)) {
+		// body is buffer
+		return null;
+	} else if (Object.prototype.toString.call(body) === '[object ArrayBuffer]') {
+		// body is ArrayBuffer
+		return null;
+	} else if (ArrayBuffer.isView(body)) {
+		// body is ArrayBufferView
+		return null;
+	} else if (typeof body.getBoundary === 'function') {
+		// detect form data input from form-data module
+		return `multipart/form-data;boundary=${body.getBoundary()}`;
+	} else if (body instanceof Stream) {
+		// body is stream
+		// can't really do much about this
+		return null;
+	} else {
+		// Body constructor defaults other things to string
+		return 'text/plain;charset=UTF-8';
+	}
+}
+
+/**
+ * The Fetch Standard treats this as if "total bytes" is a property on the body.
+ * For us, we have to explicitly get it with a function.
+ *
+ * ref: https://fetch.spec.whatwg.org/#concept-body-total-bytes
+ *
+ * @param   Body    instance   Instance of Body
+ * @return  Number?            Number of bytes, or null if not possible
+ */
+function getTotalBytes(instance) {
+	const body = instance.body;
+
+
+	if (body === null) {
+		// body is null
+		return 0;
+	} else if (isBlob(body)) {
+		return body.size;
+	} else if (Buffer.isBuffer(body)) {
+		// body is buffer
+		return body.length;
+	} else if (body && typeof body.getLengthSync === 'function') {
+		// detect form data input from form-data module
+		if (body._lengthRetrievers && body._lengthRetrievers.length == 0 || // 1.x
+		body.hasKnownLength && body.hasKnownLength()) {
+			// 2.x
+			return body.getLengthSync();
+		}
+		return null;
+	} else {
+		// body is stream
+		return null;
+	}
+}
+
+/**
+ * Write a Body to a Node.js WritableStream (e.g. http.Request) object.
+ *
+ * @param   Body    instance   Instance of Body
+ * @return  Void
+ */
+function writeToStream(dest, instance) {
+	const body = instance.body;
+
+
+	if (body === null) {
+		// body is null
+		dest.end();
+	} else if (isBlob(body)) {
+		body.stream().pipe(dest);
+	} else if (Buffer.isBuffer(body)) {
+		// body is buffer
+		dest.write(body);
+		dest.end();
+	} else {
+		// body is stream
+		body.pipe(dest);
+	}
+}
+
+// expose Promise
+Body.Promise = global.Promise;
+
+/**
+ * headers.js
+ *
+ * Headers class offers convenient helpers
+ */
+
+const invalidTokenRegex = /[^\^_`a-zA-Z\-0-9!#$%&'*+.|~]/;
+const invalidHeaderCharRegex = /[^\t\x20-\x7e\x80-\xff]/;
+
+function validateName(name) {
+	name = `${name}`;
+	if (invalidTokenRegex.test(name) || name === '') {
+		throw new TypeError(`${name} is not a legal HTTP header name`);
+	}
+}
+
+function validateValue(value) {
+	value = `${value}`;
+	if (invalidHeaderCharRegex.test(value)) {
+		throw new TypeError(`${value} is not a legal HTTP header value`);
+	}
+}
+
+/**
+ * Find the key in the map object given a header name.
+ *
+ * Returns undefined if not found.
+ *
+ * @param   String  name  Header name
+ * @return  String|Undefined
+ */
+function find(map, name) {
+	name = name.toLowerCase();
+	for (const key in map) {
+		if (key.toLowerCase() === name) {
+			return key;
+		}
+	}
+	return undefined;
+}
+
+const MAP = Symbol('map');
+class Headers {
+	/**
+  * Headers class
+  *
+  * @param   Object  headers  Response headers
+  * @return  Void
+  */
+	constructor() {
+		let init = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : undefined;
+
+		this[MAP] = Object.create(null);
+
+		if (init instanceof Headers) {
+			const rawHeaders = init.raw();
+			const headerNames = Object.keys(rawHeaders);
+
+			for (const headerName of headerNames) {
+				for (const value of rawHeaders[headerName]) {
+					this.append(headerName, value);
+				}
+			}
+
+			return;
+		}
+
+		// We don't worry about converting prop to ByteString here as append()
+		// will handle it.
+		if (init == null) ; else if (typeof init === 'object') {
+			const method = init[Symbol.iterator];
+			if (method != null) {
+				if (typeof method !== 'function') {
+					throw new TypeError('Header pairs must be iterable');
+				}
+
+				// sequence<sequence<ByteString>>
+				// Note: per spec we have to first exhaust the lists then process them
+				const pairs = [];
+				for (const pair of init) {
+					if (typeof pair !== 'object' || typeof pair[Symbol.iterator] !== 'function') {
+						throw new TypeError('Each header pair must be iterable');
+					}
+					pairs.push(Array.from(pair));
+				}
+
+				for (const pair of pairs) {
+					if (pair.length !== 2) {
+						throw new TypeError('Each header pair must be a name/value tuple');
+					}
+					this.append(pair[0], pair[1]);
+				}
+			} else {
+				// record<ByteString, ByteString>
+				for (const key of Object.keys(init)) {
+					const value = init[key];
+					this.append(key, value);
+				}
+			}
+		} else {
+			throw new TypeError('Provided initializer must be an object');
+		}
+	}
+
+	/**
+  * Return combined header value given name
+  *
+  * @param   String  name  Header name
+  * @return  Mixed
+  */
+	get(name) {
+		name = `${name}`;
+		validateName(name);
+		const key = find(this[MAP], name);
+		if (key === undefined) {
+			return null;
+		}
+
+		return this[MAP][key].join(', ');
+	}
+
+	/**
+  * Iterate over all headers
+  *
+  * @param   Function  callback  Executed for each item with parameters (value, name, thisArg)
+  * @param   Boolean   thisArg   `this` context for callback function
+  * @return  Void
+  */
+	forEach(callback) {
+		let thisArg = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : undefined;
+
+		let pairs = getHeaders(this);
+		let i = 0;
+		while (i < pairs.length) {
+			var _pairs$i = pairs[i];
+			const name = _pairs$i[0],
+			      value = _pairs$i[1];
+
+			callback.call(thisArg, value, name, this);
+			pairs = getHeaders(this);
+			i++;
+		}
+	}
+
+	/**
+  * Overwrite header values given name
+  *
+  * @param   String  name   Header name
+  * @param   String  value  Header value
+  * @return  Void
+  */
+	set(name, value) {
+		name = `${name}`;
+		value = `${value}`;
+		validateName(name);
+		validateValue(value);
+		const key = find(this[MAP], name);
+		this[MAP][key !== undefined ? key : name] = [value];
+	}
+
+	/**
+  * Append a value onto existing header
+  *
+  * @param   String  name   Header name
+  * @param   String  value  Header value
+  * @return  Void
+  */
+	append(name, value) {
+		name = `${name}`;
+		value = `${value}`;
+		validateName(name);
+		validateValue(value);
+		const key = find(this[MAP], name);
+		if (key !== undefined) {
+			this[MAP][key].push(value);
+		} else {
+			this[MAP][name] = [value];
+		}
+	}
+
+	/**
+  * Check for header name existence
+  *
+  * @param   String   name  Header name
+  * @return  Boolean
+  */
+	has(name) {
+		name = `${name}`;
+		validateName(name);
+		return find(this[MAP], name) !== undefined;
+	}
+
+	/**
+  * Delete all header values given name
+  *
+  * @param   String  name  Header name
+  * @return  Void
+  */
+	delete(name) {
+		name = `${name}`;
+		validateName(name);
+		const key = find(this[MAP], name);
+		if (key !== undefined) {
+			delete this[MAP][key];
+		}
+	}
+
+	/**
+  * Return raw headers (non-spec api)
+  *
+  * @return  Object
+  */
+	raw() {
+		return this[MAP];
+	}
+
+	/**
+  * Get an iterator on keys.
+  *
+  * @return  Iterator
+  */
+	keys() {
+		return createHeadersIterator(this, 'key');
+	}
+
+	/**
+  * Get an iterator on values.
+  *
+  * @return  Iterator
+  */
+	values() {
+		return createHeadersIterator(this, 'value');
+	}
+
+	/**
+  * Get an iterator on entries.
+  *
+  * This is the default iterator of the Headers object.
+  *
+  * @return  Iterator
+  */
+	[Symbol.iterator]() {
+		return createHeadersIterator(this, 'key+value');
+	}
+}
+Headers.prototype.entries = Headers.prototype[Symbol.iterator];
+
+Object.defineProperty(Headers.prototype, Symbol.toStringTag, {
+	value: 'Headers',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+Object.defineProperties(Headers.prototype, {
+	get: { enumerable: true },
+	forEach: { enumerable: true },
+	set: { enumerable: true },
+	append: { enumerable: true },
+	has: { enumerable: true },
+	delete: { enumerable: true },
+	keys: { enumerable: true },
+	values: { enumerable: true },
+	entries: { enumerable: true }
+});
+
+function getHeaders(headers) {
+	let kind = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 'key+value';
+
+	const keys = Object.keys(headers[MAP]).sort();
+	return keys.map(kind === 'key' ? function (k) {
+		return k.toLowerCase();
+	} : kind === 'value' ? function (k) {
+		return headers[MAP][k].join(', ');
+	} : function (k) {
+		return [k.toLowerCase(), headers[MAP][k].join(', ')];
+	});
+}
+
+const INTERNAL = Symbol('internal');
+
+function createHeadersIterator(target, kind) {
+	const iterator = Object.create(HeadersIteratorPrototype);
+	iterator[INTERNAL] = {
+		target,
+		kind,
+		index: 0
+	};
+	return iterator;
+}
+
+const HeadersIteratorPrototype = Object.setPrototypeOf({
+	next() {
+		// istanbul ignore if
+		if (!this || Object.getPrototypeOf(this) !== HeadersIteratorPrototype) {
+			throw new TypeError('Value of `this` is not a HeadersIterator');
+		}
+
+		var _INTERNAL = this[INTERNAL];
+		const target = _INTERNAL.target,
+		      kind = _INTERNAL.kind,
+		      index = _INTERNAL.index;
+
+		const values = getHeaders(target, kind);
+		const len = values.length;
+		if (index >= len) {
+			return {
+				value: undefined,
+				done: true
+			};
+		}
+
+		this[INTERNAL].index = index + 1;
+
+		return {
+			value: values[index],
+			done: false
+		};
+	}
+}, Object.getPrototypeOf(Object.getPrototypeOf([][Symbol.iterator]())));
+
+Object.defineProperty(HeadersIteratorPrototype, Symbol.toStringTag, {
+	value: 'HeadersIterator',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+/**
+ * Export the Headers object in a form that Node.js can consume.
+ *
+ * @param   Headers  headers
+ * @return  Object
+ */
+function exportNodeCompatibleHeaders(headers) {
+	const obj = Object.assign({ __proto__: null }, headers[MAP]);
+
+	// http.request() only supports string as Host header. This hack makes
+	// specifying custom Host header possible.
+	const hostHeaderKey = find(headers[MAP], 'Host');
+	if (hostHeaderKey !== undefined) {
+		obj[hostHeaderKey] = obj[hostHeaderKey][0];
+	}
+
+	return obj;
+}
+
+/**
+ * Create a Headers object from an object of headers, ignoring those that do
+ * not conform to HTTP grammar productions.
+ *
+ * @param   Object  obj  Object of headers
+ * @return  Headers
+ */
+function createHeadersLenient(obj) {
+	const headers = new Headers();
+	for (const name of Object.keys(obj)) {
+		if (invalidTokenRegex.test(name)) {
+			continue;
+		}
+		if (Array.isArray(obj[name])) {
+			for (const val of obj[name]) {
+				if (invalidHeaderCharRegex.test(val)) {
+					continue;
+				}
+				if (headers[MAP][name] === undefined) {
+					headers[MAP][name] = [val];
+				} else {
+					headers[MAP][name].push(val);
+				}
+			}
+		} else if (!invalidHeaderCharRegex.test(obj[name])) {
+			headers[MAP][name] = [obj[name]];
+		}
+	}
+	return headers;
+}
+
+const INTERNALS$1 = Symbol('Response internals');
+
+// fix an issue where "STATUS_CODES" aren't a named export for node <10
+const STATUS_CODES = http.STATUS_CODES;
+
+/**
+ * Response class
+ *
+ * @param   Stream  body  Readable stream
+ * @param   Object  opts  Response options
+ * @return  Void
+ */
+class Response {
+	constructor() {
+		let body = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : null;
+		let opts = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
+
+		Body.call(this, body, opts);
+
+		const status = opts.status || 200;
+		const headers = new Headers(opts.headers);
+
+		if (body != null && !headers.has('Content-Type')) {
+			const contentType = extractContentType(body);
+			if (contentType) {
+				headers.append('Content-Type', contentType);
+			}
+		}
+
+		this[INTERNALS$1] = {
+			url: opts.url,
+			status,
+			statusText: opts.statusText || STATUS_CODES[status],
+			headers,
+			counter: opts.counter
+		};
+	}
+
+	get url() {
+		return this[INTERNALS$1].url || '';
+	}
+
+	get status() {
+		return this[INTERNALS$1].status;
+	}
+
+	/**
+  * Convenience property representing if the request ended normally
+  */
+	get ok() {
+		return this[INTERNALS$1].status >= 200 && this[INTERNALS$1].status < 300;
+	}
+
+	get redirected() {
+		return this[INTERNALS$1].counter > 0;
+	}
+
+	get statusText() {
+		return this[INTERNALS$1].statusText;
+	}
+
+	get headers() {
+		return this[INTERNALS$1].headers;
+	}
+
+	/**
+  * Clone this response
+  *
+  * @return  Response
+  */
+	clone() {
+		return new Response(clone(this), {
+			url: this.url,
+			status: this.status,
+			statusText: this.statusText,
+			headers: this.headers,
+			ok: this.ok,
+			redirected: this.redirected
+		});
+	}
+}
+
+Body.mixIn(Response.prototype);
+
+Object.defineProperties(Response.prototype, {
+	url: { enumerable: true },
+	status: { enumerable: true },
+	ok: { enumerable: true },
+	redirected: { enumerable: true },
+	statusText: { enumerable: true },
+	headers: { enumerable: true },
+	clone: { enumerable: true }
+});
+
+Object.defineProperty(Response.prototype, Symbol.toStringTag, {
+	value: 'Response',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+const INTERNALS$2 = Symbol('Request internals');
+
+// fix an issue where "format", "parse" aren't a named export for node <10
+const parse_url = Url.parse;
+const format_url = Url.format;
+
+const streamDestructionSupported = 'destroy' in Stream.Readable.prototype;
+
+/**
+ * Check if a value is an instance of Request.
+ *
+ * @param   Mixed   input
+ * @return  Boolean
+ */
+function isRequest(input) {
+	return typeof input === 'object' && typeof input[INTERNALS$2] === 'object';
+}
+
+function isAbortSignal(signal) {
+	const proto = signal && typeof signal === 'object' && Object.getPrototypeOf(signal);
+	return !!(proto && proto.constructor.name === 'AbortSignal');
+}
+
+/**
+ * Request class
+ *
+ * @param   Mixed   input  Url or Request instance
+ * @param   Object  init   Custom options
+ * @return  Void
+ */
+class Request {
+	constructor(input) {
+		let init = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
+
+		let parsedURL;
+
+		// normalize input
+		if (!isRequest(input)) {
+			if (input && input.href) {
+				// in order to support Node.js' Url objects; though WHATWG's URL objects
+				// will fall into this branch also (since their `toString()` will return
+				// `href` property anyway)
+				parsedURL = parse_url(input.href);
+			} else {
+				// coerce input to a string before attempting to parse
+				parsedURL = parse_url(`${input}`);
+			}
+			input = {};
+		} else {
+			parsedURL = parse_url(input.url);
+		}
+
+		let method = init.method || input.method || 'GET';
+		method = method.toUpperCase();
+
+		if ((init.body != null || isRequest(input) && input.body !== null) && (method === 'GET' || method === 'HEAD')) {
+			throw new TypeError('Request with GET/HEAD method cannot have body');
+		}
+
+		let inputBody = init.body != null ? init.body : isRequest(input) && input.body !== null ? clone(input) : null;
+
+		Body.call(this, inputBody, {
+			timeout: init.timeout || input.timeout || 0,
+			size: init.size || input.size || 0
+		});
+
+		const headers = new Headers(init.headers || input.headers || {});
+
+		if (inputBody != null && !headers.has('Content-Type')) {
+			const contentType = extractContentType(inputBody);
+			if (contentType) {
+				headers.append('Content-Type', contentType);
+			}
+		}
+
+		let signal = isRequest(input) ? input.signal : null;
+		if ('signal' in init) signal = init.signal;
+
+		if (signal != null && !isAbortSignal(signal)) {
+			throw new TypeError('Expected signal to be an instanceof AbortSignal');
+		}
+
+		this[INTERNALS$2] = {
+			method,
+			redirect: init.redirect || input.redirect || 'follow',
+			headers,
+			parsedURL,
+			signal
+		};
+
+		// node-fetch-only options
+		this.follow = init.follow !== undefined ? init.follow : input.follow !== undefined ? input.follow : 20;
+		this.compress = init.compress !== undefined ? init.compress : input.compress !== undefined ? input.compress : true;
+		this.counter = init.counter || input.counter || 0;
+		this.agent = init.agent || input.agent;
+	}
+
+	get method() {
+		return this[INTERNALS$2].method;
+	}
+
+	get url() {
+		return format_url(this[INTERNALS$2].parsedURL);
+	}
+
+	get headers() {
+		return this[INTERNALS$2].headers;
+	}
+
+	get redirect() {
+		return this[INTERNALS$2].redirect;
+	}
+
+	get signal() {
+		return this[INTERNALS$2].signal;
+	}
+
+	/**
+  * Clone this request
+  *
+  * @return  Request
+  */
+	clone() {
+		return new Request(this);
+	}
+}
+
+Body.mixIn(Request.prototype);
+
+Object.defineProperty(Request.prototype, Symbol.toStringTag, {
+	value: 'Request',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+Object.defineProperties(Request.prototype, {
+	method: { enumerable: true },
+	url: { enumerable: true },
+	headers: { enumerable: true },
+	redirect: { enumerable: true },
+	clone: { enumerable: true },
+	signal: { enumerable: true }
+});
+
+/**
+ * Convert a Request to Node.js http request options.
+ *
+ * @param   Request  A Request instance
+ * @return  Object   The options object to be passed to http.request
+ */
+function getNodeRequestOptions(request) {
+	const parsedURL = request[INTERNALS$2].parsedURL;
+	const headers = new Headers(request[INTERNALS$2].headers);
+
+	// fetch step 1.3
+	if (!headers.has('Accept')) {
+		headers.set('Accept', '*/*');
+	}
+
+	// Basic fetch
+	if (!parsedURL.protocol || !parsedURL.hostname) {
+		throw new TypeError('Only absolute URLs are supported');
+	}
+
+	if (!/^https?:$/.test(parsedURL.protocol)) {
+		throw new TypeError('Only HTTP(S) protocols are supported');
+	}
+
+	if (request.signal && request.body instanceof Stream.Readable && !streamDestructionSupported) {
+		throw new Error('Cancellation of streamed requests with AbortSignal is not supported in node < 8');
+	}
+
+	// HTTP-network-or-cache fetch steps 2.4-2.7
+	let contentLengthValue = null;
+	if (request.body == null && /^(POST|PUT)$/i.test(request.method)) {
+		contentLengthValue = '0';
+	}
+	if (request.body != null) {
+		const totalBytes = getTotalBytes(request);
+		if (typeof totalBytes === 'number') {
+			contentLengthValue = String(totalBytes);
+		}
+	}
+	if (contentLengthValue) {
+		headers.set('Content-Length', contentLengthValue);
+	}
+
+	// HTTP-network-or-cache fetch step 2.11
+	if (!headers.has('User-Agent')) {
+		headers.set('User-Agent', 'node-fetch/1.0 (+https://github.com/bitinn/node-fetch)');
+	}
+
+	// HTTP-network-or-cache fetch step 2.15
+	if (request.compress && !headers.has('Accept-Encoding')) {
+		headers.set('Accept-Encoding', 'gzip,deflate');
+	}
+
+	let agent = request.agent;
+	if (typeof agent === 'function') {
+		agent = agent(parsedURL);
+	}
+
+	if (!headers.has('Connection') && !agent) {
+		headers.set('Connection', 'close');
+	}
+
+	// HTTP-network fetch step 4.2
+	// chunked encoding is handled by Node.js
+
+	return Object.assign({}, parsedURL, {
+		method: request.method,
+		headers: exportNodeCompatibleHeaders(headers),
+		agent
+	});
+}
+
+/**
+ * abort-error.js
+ *
+ * AbortError interface for cancelled requests
+ */
+
+/**
+ * Create AbortError instance
+ *
+ * @param   String      message      Error message for human
+ * @return  AbortError
+ */
+function AbortError(message) {
+  Error.call(this, message);
+
+  this.type = 'aborted';
+  this.message = message;
+
+  // hide custom error implementation details from end-users
+  Error.captureStackTrace(this, this.constructor);
+}
+
+AbortError.prototype = Object.create(Error.prototype);
+AbortError.prototype.constructor = AbortError;
+AbortError.prototype.name = 'AbortError';
+
+// fix an issue where "PassThrough", "resolve" aren't a named export for node <10
+const PassThrough$1 = Stream.PassThrough;
+const resolve_url = Url.resolve;
+
+/**
+ * Fetch function
+ *
+ * @param   Mixed    url   Absolute url or Request instance
+ * @param   Object   opts  Fetch options
+ * @return  Promise
+ */
+function fetch(url, opts) {
+
+	// allow custom promise
+	if (!fetch.Promise) {
+		throw new Error('native promise missing, set fetch.Promise to your favorite alternative');
+	}
+
+	Body.Promise = fetch.Promise;
+
+	// wrap http.request into fetch
+	return new fetch.Promise(function (resolve, reject) {
+		// build request object
+		const request = new Request(url, opts);
+		const options = getNodeRequestOptions(request);
+
+		const send = (options.protocol === 'https:' ? https : http).request;
+		const signal = request.signal;
+
+		let response = null;
+
+		const abort = function abort() {
+			let error = new AbortError('The user aborted a request.');
+			reject(error);
+			if (request.body && request.body instanceof Stream.Readable) {
+				request.body.destroy(error);
+			}
+			if (!response || !response.body) return;
+			response.body.emit('error', error);
+		};
+
+		if (signal && signal.aborted) {
+			abort();
+			return;
+		}
+
+		const abortAndFinalize = function abortAndFinalize() {
+			abort();
+			finalize();
+		};
+
+		// send request
+		const req = send(options);
+		let reqTimeout;
+
+		if (signal) {
+			signal.addEventListener('abort', abortAndFinalize);
+		}
+
+		function finalize() {
+			req.abort();
+			if (signal) signal.removeEventListener('abort', abortAndFinalize);
+			clearTimeout(reqTimeout);
+		}
+
+		if (request.timeout) {
+			req.once('socket', function (socket) {
+				reqTimeout = setTimeout(function () {
+					reject(new FetchError(`network timeout at: ${request.url}`, 'request-timeout'));
+					finalize();
+				}, request.timeout);
+			});
+		}
+
+		req.on('error', function (err) {
+			reject(new FetchError(`request to ${request.url} failed, reason: ${err.message}`, 'system', err));
+			finalize();
+		});
+
+		req.on('response', function (res) {
+			clearTimeout(reqTimeout);
+
+			const headers = createHeadersLenient(res.headers);
+
+			// HTTP fetch step 5
+			if (fetch.isRedirect(res.statusCode)) {
+				// HTTP fetch step 5.2
+				const location = headers.get('Location');
+
+				// HTTP fetch step 5.3
+				const locationURL = location === null ? null : resolve_url(request.url, location);
+
+				// HTTP fetch step 5.5
+				switch (request.redirect) {
+					case 'error':
+						reject(new FetchError(`redirect mode is set to error: ${request.url}`, 'no-redirect'));
+						finalize();
+						return;
+					case 'manual':
+						// node-fetch-specific step: make manual redirect a bit easier to use by setting the Location header value to the resolved URL.
+						if (locationURL !== null) {
+							// handle corrupted header
+							try {
+								headers.set('Location', locationURL);
+							} catch (err) {
+								// istanbul ignore next: nodejs server prevent invalid response headers, we can't test this through normal request
+								reject(err);
+							}
+						}
+						break;
+					case 'follow':
+						// HTTP-redirect fetch step 2
+						if (locationURL === null) {
+							break;
+						}
+
+						// HTTP-redirect fetch step 5
+						if (request.counter >= request.follow) {
+							reject(new FetchError(`maximum redirect reached at: ${request.url}`, 'max-redirect'));
+							finalize();
+							return;
+						}
+
+						// HTTP-redirect fetch step 6 (counter increment)
+						// Create a new Request object.
+						const requestOpts = {
+							headers: new Headers(request.headers),
+							follow: request.follow,
+							counter: request.counter + 1,
+							agent: request.agent,
+							compress: request.compress,
+							method: request.method,
+							body: request.body,
+							signal: request.signal,
+							timeout: request.timeout
+						};
+
+						// HTTP-redirect fetch step 9
+						if (res.statusCode !== 303 && request.body && getTotalBytes(request) === null) {
+							reject(new FetchError('Cannot follow redirect with body being a readable stream', 'unsupported-redirect'));
+							finalize();
+							return;
+						}
+
+						// HTTP-redirect fetch step 11
+						if (res.statusCode === 303 || (res.statusCode === 301 || res.statusCode === 302) && request.method === 'POST') {
+							requestOpts.method = 'GET';
+							requestOpts.body = undefined;
+							requestOpts.headers.delete('content-length');
+						}
+
+						// HTTP-redirect fetch step 15
+						resolve(fetch(new Request(locationURL, requestOpts)));
+						finalize();
+						return;
+				}
+			}
+
+			// prepare response
+			res.once('end', function () {
+				if (signal) signal.removeEventListener('abort', abortAndFinalize);
+			});
+			let body = res.pipe(new PassThrough$1());
+
+			const response_options = {
+				url: request.url,
+				status: res.statusCode,
+				statusText: res.statusMessage,
+				headers: headers,
+				size: request.size,
+				timeout: request.timeout,
+				counter: request.counter
+			};
+
+			// HTTP-network fetch step 12.1.1.3
+			const codings = headers.get('Content-Encoding');
+
+			// HTTP-network fetch step 12.1.1.4: handle content codings
+
+			// in following scenarios we ignore compression support
+			// 1. compression support is disabled
+			// 2. HEAD request
+			// 3. no Content-Encoding header
+			// 4. no content response (204)
+			// 5. content not modified response (304)
+			if (!request.compress || request.method === 'HEAD' || codings === null || res.statusCode === 204 || res.statusCode === 304) {
+				response = new Response(body, response_options);
+				resolve(response);
+				return;
+			}
+
+			// For Node v6+
+			// Be less strict when decoding compressed responses, since sometimes
+			// servers send slightly invalid responses that are still accepted
+			// by common browsers.
+			// Always using Z_SYNC_FLUSH is what cURL does.
+			const zlibOptions = {
+				flush: zlib.Z_SYNC_FLUSH,
+				finishFlush: zlib.Z_SYNC_FLUSH
+			};
+
+			// for gzip
+			if (codings == 'gzip' || codings == 'x-gzip') {
+				body = body.pipe(zlib.createGunzip(zlibOptions));
+				response = new Response(body, response_options);
+				resolve(response);
+				return;
+			}
+
+			// for deflate
+			if (codings == 'deflate' || codings == 'x-deflate') {
+				// handle the infamous raw deflate response from old servers
+				// a hack for old IIS and Apache servers
+				const raw = res.pipe(new PassThrough$1());
+				raw.once('data', function (chunk) {
+					// see http://stackoverflow.com/questions/37519828
+					if ((chunk[0] & 0x0F) === 0x08) {
+						body = body.pipe(zlib.createInflate());
+					} else {
+						body = body.pipe(zlib.createInflateRaw());
+					}
+					response = new Response(body, response_options);
+					resolve(response);
+				});
+				return;
+			}
+
+			// for br
+			if (codings == 'br' && typeof zlib.createBrotliDecompress === 'function') {
+				body = body.pipe(zlib.createBrotliDecompress());
+				response = new Response(body, response_options);
+				resolve(response);
+				return;
+			}
+
+			// otherwise, use response as-is
+			response = new Response(body, response_options);
+			resolve(response);
+		});
+
+		writeToStream(req, request);
+	});
+}
+/**
+ * Redirect code matching
+ *
+ * @param   Number   code  Status code
+ * @return  Boolean
+ */
+fetch.isRedirect = function (code) {
+	return code === 301 || code === 302 || code === 303 || code === 307 || code === 308;
+};
+
+// expose Promise
+fetch.Promise = global.Promise;
+
+export default fetch;
+export { Headers, Request, Response, FetchError };
diff --git a/deps/node-fetch/lib/index.js b/deps/node-fetch/lib/index.js
new file mode 100644
index 00000000000000..daa44bcafa8cf5
--- /dev/null
+++ b/deps/node-fetch/lib/index.js
@@ -0,0 +1,1642 @@
+'use strict';
+
+Object.defineProperty(exports, '__esModule', { value: true });
+
+function _interopDefault (ex) { return (ex && (typeof ex === 'object') && 'default' in ex) ? ex['default'] : ex; }
+
+var Stream = _interopDefault(require('stream'));
+var http = _interopDefault(require('http'));
+var Url = _interopDefault(require('url'));
+var https = _interopDefault(require('https'));
+var zlib = _interopDefault(require('zlib'));
+
+// Based on https://github.com/tmpvar/jsdom/blob/aa85b2abf07766ff7bf5c1f6daafb3726f2f2db5/lib/jsdom/living/blob.js
+
+// fix for "Readable" isn't a named export issue
+const Readable = Stream.Readable;
+
+const BUFFER = Symbol('buffer');
+const TYPE = Symbol('type');
+
+class Blob {
+	constructor() {
+		this[TYPE] = '';
+
+		const blobParts = arguments[0];
+		const options = arguments[1];
+
+		const buffers = [];
+		let size = 0;
+
+		if (blobParts) {
+			const a = blobParts;
+			const length = Number(a.length);
+			for (let i = 0; i < length; i++) {
+				const element = a[i];
+				let buffer;
+				if (element instanceof Buffer) {
+					buffer = element;
+				} else if (ArrayBuffer.isView(element)) {
+					buffer = Buffer.from(element.buffer, element.byteOffset, element.byteLength);
+				} else if (element instanceof ArrayBuffer) {
+					buffer = Buffer.from(element);
+				} else if (element instanceof Blob) {
+					buffer = element[BUFFER];
+				} else {
+					buffer = Buffer.from(typeof element === 'string' ? element : String(element));
+				}
+				size += buffer.length;
+				buffers.push(buffer);
+			}
+		}
+
+		this[BUFFER] = Buffer.concat(buffers);
+
+		let type = options && options.type !== undefined && String(options.type).toLowerCase();
+		if (type && !/[^\u0020-\u007E]/.test(type)) {
+			this[TYPE] = type;
+		}
+	}
+	get size() {
+		return this[BUFFER].length;
+	}
+	get type() {
+		return this[TYPE];
+	}
+	text() {
+		return Promise.resolve(this[BUFFER].toString());
+	}
+	arrayBuffer() {
+		const buf = this[BUFFER];
+		const ab = buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength);
+		return Promise.resolve(ab);
+	}
+	stream() {
+		const readable = new Readable();
+		readable._read = function () {};
+		readable.push(this[BUFFER]);
+		readable.push(null);
+		return readable;
+	}
+	toString() {
+		return '[object Blob]';
+	}
+	slice() {
+		const size = this.size;
+
+		const start = arguments[0];
+		const end = arguments[1];
+		let relativeStart, relativeEnd;
+		if (start === undefined) {
+			relativeStart = 0;
+		} else if (start < 0) {
+			relativeStart = Math.max(size + start, 0);
+		} else {
+			relativeStart = Math.min(start, size);
+		}
+		if (end === undefined) {
+			relativeEnd = size;
+		} else if (end < 0) {
+			relativeEnd = Math.max(size + end, 0);
+		} else {
+			relativeEnd = Math.min(end, size);
+		}
+		const span = Math.max(relativeEnd - relativeStart, 0);
+
+		const buffer = this[BUFFER];
+		const slicedBuffer = buffer.slice(relativeStart, relativeStart + span);
+		const blob = new Blob([], { type: arguments[2] });
+		blob[BUFFER] = slicedBuffer;
+		return blob;
+	}
+}
+
+Object.defineProperties(Blob.prototype, {
+	size: { enumerable: true },
+	type: { enumerable: true },
+	slice: { enumerable: true }
+});
+
+Object.defineProperty(Blob.prototype, Symbol.toStringTag, {
+	value: 'Blob',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+/**
+ * fetch-error.js
+ *
+ * FetchError interface for operational errors
+ */
+
+/**
+ * Create FetchError instance
+ *
+ * @param   String      message      Error message for human
+ * @param   String      type         Error type for machine
+ * @param   String      systemError  For Node.js system error
+ * @return  FetchError
+ */
+function FetchError(message, type, systemError) {
+  Error.call(this, message);
+
+  this.message = message;
+  this.type = type;
+
+  // when err.type is `system`, err.code contains system error code
+  if (systemError) {
+    this.code = this.errno = systemError.code;
+  }
+
+  // hide custom error implementation details from end-users
+  Error.captureStackTrace(this, this.constructor);
+}
+
+FetchError.prototype = Object.create(Error.prototype);
+FetchError.prototype.constructor = FetchError;
+FetchError.prototype.name = 'FetchError';
+
+let convert;
+try {
+	convert = require('encoding').convert;
+} catch (e) {}
+
+const INTERNALS = Symbol('Body internals');
+
+// fix an issue where "PassThrough" isn't a named export for node <10
+const PassThrough = Stream.PassThrough;
+
+/**
+ * Body mixin
+ *
+ * Ref: https://fetch.spec.whatwg.org/#body
+ *
+ * @param   Stream  body  Readable stream
+ * @param   Object  opts  Response options
+ * @return  Void
+ */
+function Body(body) {
+	var _this = this;
+
+	var _ref = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {},
+	    _ref$size = _ref.size;
+
+	let size = _ref$size === undefined ? 0 : _ref$size;
+	var _ref$timeout = _ref.timeout;
+	let timeout = _ref$timeout === undefined ? 0 : _ref$timeout;
+
+	if (body == null) {
+		// body is undefined or null
+		body = null;
+	} else if (isURLSearchParams(body)) {
+		// body is a URLSearchParams
+		body = Buffer.from(body.toString());
+	} else if (isBlob(body)) ; else if (Buffer.isBuffer(body)) ; else if (Object.prototype.toString.call(body) === '[object ArrayBuffer]') {
+		// body is ArrayBuffer
+		body = Buffer.from(body);
+	} else if (ArrayBuffer.isView(body)) {
+		// body is ArrayBufferView
+		body = Buffer.from(body.buffer, body.byteOffset, body.byteLength);
+	} else if (body instanceof Stream) ; else {
+		// none of the above
+		// coerce to string then buffer
+		body = Buffer.from(String(body));
+	}
+	this[INTERNALS] = {
+		body,
+		disturbed: false,
+		error: null
+	};
+	this.size = size;
+	this.timeout = timeout;
+
+	if (body instanceof Stream) {
+		body.on('error', function (err) {
+			const error = err.name === 'AbortError' ? err : new FetchError(`Invalid response body while trying to fetch ${_this.url}: ${err.message}`, 'system', err);
+			_this[INTERNALS].error = error;
+		});
+	}
+}
+
+Body.prototype = {
+	get body() {
+		return this[INTERNALS].body;
+	},
+
+	get bodyUsed() {
+		return this[INTERNALS].disturbed;
+	},
+
+	/**
+  * Decode response as ArrayBuffer
+  *
+  * @return  Promise
+  */
+	arrayBuffer() {
+		return consumeBody.call(this).then(function (buf) {
+			return buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength);
+		});
+	},
+
+	/**
+  * Return raw response as Blob
+  *
+  * @return Promise
+  */
+	blob() {
+		let ct = this.headers && this.headers.get('content-type') || '';
+		return consumeBody.call(this).then(function (buf) {
+			return Object.assign(
+			// Prevent copying
+			new Blob([], {
+				type: ct.toLowerCase()
+			}), {
+				[BUFFER]: buf
+			});
+		});
+	},
+
+	/**
+  * Decode response as json
+  *
+  * @return  Promise
+  */
+	json() {
+		var _this2 = this;
+
+		return consumeBody.call(this).then(function (buffer) {
+			try {
+				return JSON.parse(buffer.toString());
+			} catch (err) {
+				return Body.Promise.reject(new FetchError(`invalid json response body at ${_this2.url} reason: ${err.message}`, 'invalid-json'));
+			}
+		});
+	},
+
+	/**
+  * Decode response as text
+  *
+  * @return  Promise
+  */
+	text() {
+		return consumeBody.call(this).then(function (buffer) {
+			return buffer.toString();
+		});
+	},
+
+	/**
+  * Decode response as buffer (non-spec api)
+  *
+  * @return  Promise
+  */
+	buffer() {
+		return consumeBody.call(this);
+	},
+
+	/**
+  * Decode response as text, while automatically detecting the encoding and
+  * trying to decode to UTF-8 (non-spec api)
+  *
+  * @return  Promise
+  */
+	textConverted() {
+		var _this3 = this;
+
+		return consumeBody.call(this).then(function (buffer) {
+			return convertBody(buffer, _this3.headers);
+		});
+	}
+};
+
+// In browsers, all properties are enumerable.
+Object.defineProperties(Body.prototype, {
+	body: { enumerable: true },
+	bodyUsed: { enumerable: true },
+	arrayBuffer: { enumerable: true },
+	blob: { enumerable: true },
+	json: { enumerable: true },
+	text: { enumerable: true }
+});
+
+Body.mixIn = function (proto) {
+	for (const name of Object.getOwnPropertyNames(Body.prototype)) {
+		// istanbul ignore else: future proof
+		if (!(name in proto)) {
+			const desc = Object.getOwnPropertyDescriptor(Body.prototype, name);
+			Object.defineProperty(proto, name, desc);
+		}
+	}
+};
+
+/**
+ * Consume and convert an entire Body to a Buffer.
+ *
+ * Ref: https://fetch.spec.whatwg.org/#concept-body-consume-body
+ *
+ * @return  Promise
+ */
+function consumeBody() {
+	var _this4 = this;
+
+	if (this[INTERNALS].disturbed) {
+		return Body.Promise.reject(new TypeError(`body used already for: ${this.url}`));
+	}
+
+	this[INTERNALS].disturbed = true;
+
+	if (this[INTERNALS].error) {
+		return Body.Promise.reject(this[INTERNALS].error);
+	}
+
+	let body = this.body;
+
+	// body is null
+	if (body === null) {
+		return Body.Promise.resolve(Buffer.alloc(0));
+	}
+
+	// body is blob
+	if (isBlob(body)) {
+		body = body.stream();
+	}
+
+	// body is buffer
+	if (Buffer.isBuffer(body)) {
+		return Body.Promise.resolve(body);
+	}
+
+	// istanbul ignore if: should never happen
+	if (!(body instanceof Stream)) {
+		return Body.Promise.resolve(Buffer.alloc(0));
+	}
+
+	// body is stream
+	// get ready to actually consume the body
+	let accum = [];
+	let accumBytes = 0;
+	let abort = false;
+
+	return new Body.Promise(function (resolve, reject) {
+		let resTimeout;
+
+		// allow timeout on slow response body
+		if (_this4.timeout) {
+			resTimeout = setTimeout(function () {
+				abort = true;
+				reject(new FetchError(`Response timeout while trying to fetch ${_this4.url} (over ${_this4.timeout}ms)`, 'body-timeout'));
+			}, _this4.timeout);
+		}
+
+		// handle stream errors
+		body.on('error', function (err) {
+			if (err.name === 'AbortError') {
+				// if the request was aborted, reject with this Error
+				abort = true;
+				reject(err);
+			} else {
+				// other errors, such as incorrect content-encoding
+				reject(new FetchError(`Invalid response body while trying to fetch ${_this4.url}: ${err.message}`, 'system', err));
+			}
+		});
+
+		body.on('data', function (chunk) {
+			if (abort || chunk === null) {
+				return;
+			}
+
+			if (_this4.size && accumBytes + chunk.length > _this4.size) {
+				abort = true;
+				reject(new FetchError(`content size at ${_this4.url} over limit: ${_this4.size}`, 'max-size'));
+				return;
+			}
+
+			accumBytes += chunk.length;
+			accum.push(chunk);
+		});
+
+		body.on('end', function () {
+			if (abort) {
+				return;
+			}
+
+			clearTimeout(resTimeout);
+
+			try {
+				resolve(Buffer.concat(accum, accumBytes));
+			} catch (err) {
+				// handle streams that have accumulated too much data (issue #414)
+				reject(new FetchError(`Could not create Buffer from response body for ${_this4.url}: ${err.message}`, 'system', err));
+			}
+		});
+	});
+}
+
+/**
+ * Detect buffer encoding and convert to target encoding
+ * ref: http://www.w3.org/TR/2011/WD-html5-20110113/parsing.html#determining-the-character-encoding
+ *
+ * @param   Buffer  buffer    Incoming buffer
+ * @param   String  encoding  Target encoding
+ * @return  String
+ */
+function convertBody(buffer, headers) {
+	if (typeof convert !== 'function') {
+		throw new Error('The package `encoding` must be installed to use the textConverted() function');
+	}
+
+	const ct = headers.get('content-type');
+	let charset = 'utf-8';
+	let res, str;
+
+	// header
+	if (ct) {
+		res = /charset=([^;]*)/i.exec(ct);
+	}
+
+	// no charset in content type, peek at response body for at most 1024 bytes
+	str = buffer.slice(0, 1024).toString();
+
+	// html5
+	if (!res && str) {
+		res = /<meta.+?charset=(['"])(.+?)\1/i.exec(str);
+	}
+
+	// html4
+	if (!res && str) {
+		res = /<meta[\s]+?http-equiv=(['"])content-type\1[\s]+?content=(['"])(.+?)\2/i.exec(str);
+
+		if (res) {
+			res = /charset=(.*)/i.exec(res.pop());
+		}
+	}
+
+	// xml
+	if (!res && str) {
+		res = /<\?xml.+?encoding=(['"])(.+?)\1/i.exec(str);
+	}
+
+	// found charset
+	if (res) {
+		charset = res.pop();
+
+		// prevent decode issues when sites use incorrect encoding
+		// ref: https://hsivonen.fi/encoding-menu/
+		if (charset === 'gb2312' || charset === 'gbk') {
+			charset = 'gb18030';
+		}
+	}
+
+	// turn raw buffers into a single utf-8 buffer
+	return convert(buffer, 'UTF-8', charset).toString();
+}
+
+/**
+ * Detect a URLSearchParams object
+ * ref: https://github.com/bitinn/node-fetch/issues/296#issuecomment-307598143
+ *
+ * @param   Object  obj     Object to detect by type or brand
+ * @return  String
+ */
+function isURLSearchParams(obj) {
+	// Duck-typing as a necessary condition.
+	if (typeof obj !== 'object' || typeof obj.append !== 'function' || typeof obj.delete !== 'function' || typeof obj.get !== 'function' || typeof obj.getAll !== 'function' || typeof obj.has !== 'function' || typeof obj.set !== 'function') {
+		return false;
+	}
+
+	// Brand-checking and more duck-typing as optional condition.
+	return obj.constructor.name === 'URLSearchParams' || Object.prototype.toString.call(obj) === '[object URLSearchParams]' || typeof obj.sort === 'function';
+}
+
+/**
+ * Check if `obj` is a W3C `Blob` object (which `File` inherits from)
+ * @param  {*} obj
+ * @return {boolean}
+ */
+function isBlob(obj) {
+	return typeof obj === 'object' && typeof obj.arrayBuffer === 'function' && typeof obj.type === 'string' && typeof obj.stream === 'function' && typeof obj.constructor === 'function' && typeof obj.constructor.name === 'string' && /^(Blob|File)$/.test(obj.constructor.name) && /^(Blob|File)$/.test(obj[Symbol.toStringTag]);
+}
+
+/**
+ * Clone body given Res/Req instance
+ *
+ * @param   Mixed  instance  Response or Request instance
+ * @return  Mixed
+ */
+function clone(instance) {
+	let p1, p2;
+	let body = instance.body;
+
+	// don't allow cloning a used body
+	if (instance.bodyUsed) {
+		throw new Error('cannot clone body after it is used');
+	}
+
+	// check that body is a stream and not form-data object
+	// note: we can't clone the form-data object without having it as a dependency
+	if (body instanceof Stream && typeof body.getBoundary !== 'function') {
+		// tee instance body
+		p1 = new PassThrough();
+		p2 = new PassThrough();
+		body.pipe(p1);
+		body.pipe(p2);
+		// set instance body to teed body and return the other teed body
+		instance[INTERNALS].body = p1;
+		body = p2;
+	}
+
+	return body;
+}
+
+/**
+ * Performs the operation "extract a `Content-Type` value from |object|" as
+ * specified in the specification:
+ * https://fetch.spec.whatwg.org/#concept-bodyinit-extract
+ *
+ * This function assumes that instance.body is present.
+ *
+ * @param   Mixed  instance  Any options.body input
+ */
+function extractContentType(body) {
+	if (body === null) {
+		// body is null
+		return null;
+	} else if (typeof body === 'string') {
+		// body is string
+		return 'text/plain;charset=UTF-8';
+	} else if (isURLSearchParams(body)) {
+		// body is a URLSearchParams
+		return 'application/x-www-form-urlencoded;charset=UTF-8';
+	} else if (isBlob(body)) {
+		// body is blob
+		return body.type || null;
+	} else if (Buffer.isBuffer(body)) {
+		// body is buffer
+		return null;
+	} else if (Object.prototype.toString.call(body) === '[object ArrayBuffer]') {
+		// body is ArrayBuffer
+		return null;
+	} else if (ArrayBuffer.isView(body)) {
+		// body is ArrayBufferView
+		return null;
+	} else if (typeof body.getBoundary === 'function') {
+		// detect form data input from form-data module
+		return `multipart/form-data;boundary=${body.getBoundary()}`;
+	} else if (body instanceof Stream) {
+		// body is stream
+		// can't really do much about this
+		return null;
+	} else {
+		// Body constructor defaults other things to string
+		return 'text/plain;charset=UTF-8';
+	}
+}
+
+/**
+ * The Fetch Standard treats this as if "total bytes" is a property on the body.
+ * For us, we have to explicitly get it with a function.
+ *
+ * ref: https://fetch.spec.whatwg.org/#concept-body-total-bytes
+ *
+ * @param   Body    instance   Instance of Body
+ * @return  Number?            Number of bytes, or null if not possible
+ */
+function getTotalBytes(instance) {
+	const body = instance.body;
+
+
+	if (body === null) {
+		// body is null
+		return 0;
+	} else if (isBlob(body)) {
+		return body.size;
+	} else if (Buffer.isBuffer(body)) {
+		// body is buffer
+		return body.length;
+	} else if (body && typeof body.getLengthSync === 'function') {
+		// detect form data input from form-data module
+		if (body._lengthRetrievers && body._lengthRetrievers.length == 0 || // 1.x
+		body.hasKnownLength && body.hasKnownLength()) {
+			// 2.x
+			return body.getLengthSync();
+		}
+		return null;
+	} else {
+		// body is stream
+		return null;
+	}
+}
+
+/**
+ * Write a Body to a Node.js WritableStream (e.g. http.Request) object.
+ *
+ * @param   Body    instance   Instance of Body
+ * @return  Void
+ */
+function writeToStream(dest, instance) {
+	const body = instance.body;
+
+
+	if (body === null) {
+		// body is null
+		dest.end();
+	} else if (isBlob(body)) {
+		body.stream().pipe(dest);
+	} else if (Buffer.isBuffer(body)) {
+		// body is buffer
+		dest.write(body);
+		dest.end();
+	} else {
+		// body is stream
+		body.pipe(dest);
+	}
+}
+
+// expose Promise
+Body.Promise = global.Promise;
+
+/**
+ * headers.js
+ *
+ * Headers class offers convenient helpers
+ */
+
+const invalidTokenRegex = /[^\^_`a-zA-Z\-0-9!#$%&'*+.|~]/;
+const invalidHeaderCharRegex = /[^\t\x20-\x7e\x80-\xff]/;
+
+function validateName(name) {
+	name = `${name}`;
+	if (invalidTokenRegex.test(name) || name === '') {
+		throw new TypeError(`${name} is not a legal HTTP header name`);
+	}
+}
+
+function validateValue(value) {
+	value = `${value}`;
+	if (invalidHeaderCharRegex.test(value)) {
+		throw new TypeError(`${value} is not a legal HTTP header value`);
+	}
+}
+
+/**
+ * Find the key in the map object given a header name.
+ *
+ * Returns undefined if not found.
+ *
+ * @param   String  name  Header name
+ * @return  String|Undefined
+ */
+function find(map, name) {
+	name = name.toLowerCase();
+	for (const key in map) {
+		if (key.toLowerCase() === name) {
+			return key;
+		}
+	}
+	return undefined;
+}
+
+const MAP = Symbol('map');
+class Headers {
+	/**
+  * Headers class
+  *
+  * @param   Object  headers  Response headers
+  * @return  Void
+  */
+	constructor() {
+		let init = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : undefined;
+
+		this[MAP] = Object.create(null);
+
+		if (init instanceof Headers) {
+			const rawHeaders = init.raw();
+			const headerNames = Object.keys(rawHeaders);
+
+			for (const headerName of headerNames) {
+				for (const value of rawHeaders[headerName]) {
+					this.append(headerName, value);
+				}
+			}
+
+			return;
+		}
+
+		// We don't worry about converting prop to ByteString here as append()
+		// will handle it.
+		if (init == null) ; else if (typeof init === 'object') {
+			const method = init[Symbol.iterator];
+			if (method != null) {
+				if (typeof method !== 'function') {
+					throw new TypeError('Header pairs must be iterable');
+				}
+
+				// sequence<sequence<ByteString>>
+				// Note: per spec we have to first exhaust the lists then process them
+				const pairs = [];
+				for (const pair of init) {
+					if (typeof pair !== 'object' || typeof pair[Symbol.iterator] !== 'function') {
+						throw new TypeError('Each header pair must be iterable');
+					}
+					pairs.push(Array.from(pair));
+				}
+
+				for (const pair of pairs) {
+					if (pair.length !== 2) {
+						throw new TypeError('Each header pair must be a name/value tuple');
+					}
+					this.append(pair[0], pair[1]);
+				}
+			} else {
+				// record<ByteString, ByteString>
+				for (const key of Object.keys(init)) {
+					const value = init[key];
+					this.append(key, value);
+				}
+			}
+		} else {
+			throw new TypeError('Provided initializer must be an object');
+		}
+	}
+
+	/**
+  * Return combined header value given name
+  *
+  * @param   String  name  Header name
+  * @return  Mixed
+  */
+	get(name) {
+		name = `${name}`;
+		validateName(name);
+		const key = find(this[MAP], name);
+		if (key === undefined) {
+			return null;
+		}
+
+		return this[MAP][key].join(', ');
+	}
+
+	/**
+  * Iterate over all headers
+  *
+  * @param   Function  callback  Executed for each item with parameters (value, name, thisArg)
+  * @param   Boolean   thisArg   `this` context for callback function
+  * @return  Void
+  */
+	forEach(callback) {
+		let thisArg = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : undefined;
+
+		let pairs = getHeaders(this);
+		let i = 0;
+		while (i < pairs.length) {
+			var _pairs$i = pairs[i];
+			const name = _pairs$i[0],
+			      value = _pairs$i[1];
+
+			callback.call(thisArg, value, name, this);
+			pairs = getHeaders(this);
+			i++;
+		}
+	}
+
+	/**
+  * Overwrite header values given name
+  *
+  * @param   String  name   Header name
+  * @param   String  value  Header value
+  * @return  Void
+  */
+	set(name, value) {
+		name = `${name}`;
+		value = `${value}`;
+		validateName(name);
+		validateValue(value);
+		const key = find(this[MAP], name);
+		this[MAP][key !== undefined ? key : name] = [value];
+	}
+
+	/**
+  * Append a value onto existing header
+  *
+  * @param   String  name   Header name
+  * @param   String  value  Header value
+  * @return  Void
+  */
+	append(name, value) {
+		name = `${name}`;
+		value = `${value}`;
+		validateName(name);
+		validateValue(value);
+		const key = find(this[MAP], name);
+		if (key !== undefined) {
+			this[MAP][key].push(value);
+		} else {
+			this[MAP][name] = [value];
+		}
+	}
+
+	/**
+  * Check for header name existence
+  *
+  * @param   String   name  Header name
+  * @return  Boolean
+  */
+	has(name) {
+		name = `${name}`;
+		validateName(name);
+		return find(this[MAP], name) !== undefined;
+	}
+
+	/**
+  * Delete all header values given name
+  *
+  * @param   String  name  Header name
+  * @return  Void
+  */
+	delete(name) {
+		name = `${name}`;
+		validateName(name);
+		const key = find(this[MAP], name);
+		if (key !== undefined) {
+			delete this[MAP][key];
+		}
+	}
+
+	/**
+  * Return raw headers (non-spec api)
+  *
+  * @return  Object
+  */
+	raw() {
+		return this[MAP];
+	}
+
+	/**
+  * Get an iterator on keys.
+  *
+  * @return  Iterator
+  */
+	keys() {
+		return createHeadersIterator(this, 'key');
+	}
+
+	/**
+  * Get an iterator on values.
+  *
+  * @return  Iterator
+  */
+	values() {
+		return createHeadersIterator(this, 'value');
+	}
+
+	/**
+  * Get an iterator on entries.
+  *
+  * This is the default iterator of the Headers object.
+  *
+  * @return  Iterator
+  */
+	[Symbol.iterator]() {
+		return createHeadersIterator(this, 'key+value');
+	}
+}
+Headers.prototype.entries = Headers.prototype[Symbol.iterator];
+
+Object.defineProperty(Headers.prototype, Symbol.toStringTag, {
+	value: 'Headers',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+Object.defineProperties(Headers.prototype, {
+	get: { enumerable: true },
+	forEach: { enumerable: true },
+	set: { enumerable: true },
+	append: { enumerable: true },
+	has: { enumerable: true },
+	delete: { enumerable: true },
+	keys: { enumerable: true },
+	values: { enumerable: true },
+	entries: { enumerable: true }
+});
+
+function getHeaders(headers) {
+	let kind = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 'key+value';
+
+	const keys = Object.keys(headers[MAP]).sort();
+	return keys.map(kind === 'key' ? function (k) {
+		return k.toLowerCase();
+	} : kind === 'value' ? function (k) {
+		return headers[MAP][k].join(', ');
+	} : function (k) {
+		return [k.toLowerCase(), headers[MAP][k].join(', ')];
+	});
+}
+
+const INTERNAL = Symbol('internal');
+
+function createHeadersIterator(target, kind) {
+	const iterator = Object.create(HeadersIteratorPrototype);
+	iterator[INTERNAL] = {
+		target,
+		kind,
+		index: 0
+	};
+	return iterator;
+}
+
+const HeadersIteratorPrototype = Object.setPrototypeOf({
+	next() {
+		// istanbul ignore if
+		if (!this || Object.getPrototypeOf(this) !== HeadersIteratorPrototype) {
+			throw new TypeError('Value of `this` is not a HeadersIterator');
+		}
+
+		var _INTERNAL = this[INTERNAL];
+		const target = _INTERNAL.target,
+		      kind = _INTERNAL.kind,
+		      index = _INTERNAL.index;
+
+		const values = getHeaders(target, kind);
+		const len = values.length;
+		if (index >= len) {
+			return {
+				value: undefined,
+				done: true
+			};
+		}
+
+		this[INTERNAL].index = index + 1;
+
+		return {
+			value: values[index],
+			done: false
+		};
+	}
+}, Object.getPrototypeOf(Object.getPrototypeOf([][Symbol.iterator]())));
+
+Object.defineProperty(HeadersIteratorPrototype, Symbol.toStringTag, {
+	value: 'HeadersIterator',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+/**
+ * Export the Headers object in a form that Node.js can consume.
+ *
+ * @param   Headers  headers
+ * @return  Object
+ */
+function exportNodeCompatibleHeaders(headers) {
+	const obj = Object.assign({ __proto__: null }, headers[MAP]);
+
+	// http.request() only supports string as Host header. This hack makes
+	// specifying custom Host header possible.
+	const hostHeaderKey = find(headers[MAP], 'Host');
+	if (hostHeaderKey !== undefined) {
+		obj[hostHeaderKey] = obj[hostHeaderKey][0];
+	}
+
+	return obj;
+}
+
+/**
+ * Create a Headers object from an object of headers, ignoring those that do
+ * not conform to HTTP grammar productions.
+ *
+ * @param   Object  obj  Object of headers
+ * @return  Headers
+ */
+function createHeadersLenient(obj) {
+	const headers = new Headers();
+	for (const name of Object.keys(obj)) {
+		if (invalidTokenRegex.test(name)) {
+			continue;
+		}
+		if (Array.isArray(obj[name])) {
+			for (const val of obj[name]) {
+				if (invalidHeaderCharRegex.test(val)) {
+					continue;
+				}
+				if (headers[MAP][name] === undefined) {
+					headers[MAP][name] = [val];
+				} else {
+					headers[MAP][name].push(val);
+				}
+			}
+		} else if (!invalidHeaderCharRegex.test(obj[name])) {
+			headers[MAP][name] = [obj[name]];
+		}
+	}
+	return headers;
+}
+
+const INTERNALS$1 = Symbol('Response internals');
+
+// fix an issue where "STATUS_CODES" aren't a named export for node <10
+const STATUS_CODES = http.STATUS_CODES;
+
+/**
+ * Response class
+ *
+ * @param   Stream  body  Readable stream
+ * @param   Object  opts  Response options
+ * @return  Void
+ */
+class Response {
+	constructor() {
+		let body = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : null;
+		let opts = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
+
+		Body.call(this, body, opts);
+
+		const status = opts.status || 200;
+		const headers = new Headers(opts.headers);
+
+		if (body != null && !headers.has('Content-Type')) {
+			const contentType = extractContentType(body);
+			if (contentType) {
+				headers.append('Content-Type', contentType);
+			}
+		}
+
+		this[INTERNALS$1] = {
+			url: opts.url,
+			status,
+			statusText: opts.statusText || STATUS_CODES[status],
+			headers,
+			counter: opts.counter
+		};
+	}
+
+	get url() {
+		return this[INTERNALS$1].url || '';
+	}
+
+	get status() {
+		return this[INTERNALS$1].status;
+	}
+
+	/**
+  * Convenience property representing if the request ended normally
+  */
+	get ok() {
+		return this[INTERNALS$1].status >= 200 && this[INTERNALS$1].status < 300;
+	}
+
+	get redirected() {
+		return this[INTERNALS$1].counter > 0;
+	}
+
+	get statusText() {
+		return this[INTERNALS$1].statusText;
+	}
+
+	get headers() {
+		return this[INTERNALS$1].headers;
+	}
+
+	/**
+  * Clone this response
+  *
+  * @return  Response
+  */
+	clone() {
+		return new Response(clone(this), {
+			url: this.url,
+			status: this.status,
+			statusText: this.statusText,
+			headers: this.headers,
+			ok: this.ok,
+			redirected: this.redirected
+		});
+	}
+}
+
+Body.mixIn(Response.prototype);
+
+Object.defineProperties(Response.prototype, {
+	url: { enumerable: true },
+	status: { enumerable: true },
+	ok: { enumerable: true },
+	redirected: { enumerable: true },
+	statusText: { enumerable: true },
+	headers: { enumerable: true },
+	clone: { enumerable: true }
+});
+
+Object.defineProperty(Response.prototype, Symbol.toStringTag, {
+	value: 'Response',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+const INTERNALS$2 = Symbol('Request internals');
+
+// fix an issue where "format", "parse" aren't a named export for node <10
+const parse_url = Url.parse;
+const format_url = Url.format;
+
+const streamDestructionSupported = 'destroy' in Stream.Readable.prototype;
+
+/**
+ * Check if a value is an instance of Request.
+ *
+ * @param   Mixed   input
+ * @return  Boolean
+ */
+function isRequest(input) {
+	return typeof input === 'object' && typeof input[INTERNALS$2] === 'object';
+}
+
+function isAbortSignal(signal) {
+	const proto = signal && typeof signal === 'object' && Object.getPrototypeOf(signal);
+	return !!(proto && proto.constructor.name === 'AbortSignal');
+}
+
+/**
+ * Request class
+ *
+ * @param   Mixed   input  Url or Request instance
+ * @param   Object  init   Custom options
+ * @return  Void
+ */
+class Request {
+	constructor(input) {
+		let init = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
+
+		let parsedURL;
+
+		// normalize input
+		if (!isRequest(input)) {
+			if (input && input.href) {
+				// in order to support Node.js' Url objects; though WHATWG's URL objects
+				// will fall into this branch also (since their `toString()` will return
+				// `href` property anyway)
+				parsedURL = parse_url(input.href);
+			} else {
+				// coerce input to a string before attempting to parse
+				parsedURL = parse_url(`${input}`);
+			}
+			input = {};
+		} else {
+			parsedURL = parse_url(input.url);
+		}
+
+		let method = init.method || input.method || 'GET';
+		method = method.toUpperCase();
+
+		if ((init.body != null || isRequest(input) && input.body !== null) && (method === 'GET' || method === 'HEAD')) {
+			throw new TypeError('Request with GET/HEAD method cannot have body');
+		}
+
+		let inputBody = init.body != null ? init.body : isRequest(input) && input.body !== null ? clone(input) : null;
+
+		Body.call(this, inputBody, {
+			timeout: init.timeout || input.timeout || 0,
+			size: init.size || input.size || 0
+		});
+
+		const headers = new Headers(init.headers || input.headers || {});
+
+		if (inputBody != null && !headers.has('Content-Type')) {
+			const contentType = extractContentType(inputBody);
+			if (contentType) {
+				headers.append('Content-Type', contentType);
+			}
+		}
+
+		let signal = isRequest(input) ? input.signal : null;
+		if ('signal' in init) signal = init.signal;
+
+		if (signal != null && !isAbortSignal(signal)) {
+			throw new TypeError('Expected signal to be an instanceof AbortSignal');
+		}
+
+		this[INTERNALS$2] = {
+			method,
+			redirect: init.redirect || input.redirect || 'follow',
+			headers,
+			parsedURL,
+			signal
+		};
+
+		// node-fetch-only options
+		this.follow = init.follow !== undefined ? init.follow : input.follow !== undefined ? input.follow : 20;
+		this.compress = init.compress !== undefined ? init.compress : input.compress !== undefined ? input.compress : true;
+		this.counter = init.counter || input.counter || 0;
+		this.agent = init.agent || input.agent;
+	}
+
+	get method() {
+		return this[INTERNALS$2].method;
+	}
+
+	get url() {
+		return format_url(this[INTERNALS$2].parsedURL);
+	}
+
+	get headers() {
+		return this[INTERNALS$2].headers;
+	}
+
+	get redirect() {
+		return this[INTERNALS$2].redirect;
+	}
+
+	get signal() {
+		return this[INTERNALS$2].signal;
+	}
+
+	/**
+  * Clone this request
+  *
+  * @return  Request
+  */
+	clone() {
+		return new Request(this);
+	}
+}
+
+Body.mixIn(Request.prototype);
+
+Object.defineProperty(Request.prototype, Symbol.toStringTag, {
+	value: 'Request',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+Object.defineProperties(Request.prototype, {
+	method: { enumerable: true },
+	url: { enumerable: true },
+	headers: { enumerable: true },
+	redirect: { enumerable: true },
+	clone: { enumerable: true },
+	signal: { enumerable: true }
+});
+
+/**
+ * Convert a Request to Node.js http request options.
+ *
+ * @param   Request  A Request instance
+ * @return  Object   The options object to be passed to http.request
+ */
+function getNodeRequestOptions(request) {
+	const parsedURL = request[INTERNALS$2].parsedURL;
+	const headers = new Headers(request[INTERNALS$2].headers);
+
+	// fetch step 1.3
+	if (!headers.has('Accept')) {
+		headers.set('Accept', '*/*');
+	}
+
+	// Basic fetch
+	if (!parsedURL.protocol || !parsedURL.hostname) {
+		throw new TypeError('Only absolute URLs are supported');
+	}
+
+	if (!/^https?:$/.test(parsedURL.protocol)) {
+		throw new TypeError('Only HTTP(S) protocols are supported');
+	}
+
+	if (request.signal && request.body instanceof Stream.Readable && !streamDestructionSupported) {
+		throw new Error('Cancellation of streamed requests with AbortSignal is not supported in node < 8');
+	}
+
+	// HTTP-network-or-cache fetch steps 2.4-2.7
+	let contentLengthValue = null;
+	if (request.body == null && /^(POST|PUT)$/i.test(request.method)) {
+		contentLengthValue = '0';
+	}
+	if (request.body != null) {
+		const totalBytes = getTotalBytes(request);
+		if (typeof totalBytes === 'number') {
+			contentLengthValue = String(totalBytes);
+		}
+	}
+	if (contentLengthValue) {
+		headers.set('Content-Length', contentLengthValue);
+	}
+
+	// HTTP-network-or-cache fetch step 2.11
+	if (!headers.has('User-Agent')) {
+		headers.set('User-Agent', 'node-fetch/1.0 (+https://github.com/bitinn/node-fetch)');
+	}
+
+	// HTTP-network-or-cache fetch step 2.15
+	if (request.compress && !headers.has('Accept-Encoding')) {
+		headers.set('Accept-Encoding', 'gzip,deflate');
+	}
+
+	let agent = request.agent;
+	if (typeof agent === 'function') {
+		agent = agent(parsedURL);
+	}
+
+	if (!headers.has('Connection') && !agent) {
+		headers.set('Connection', 'close');
+	}
+
+	// HTTP-network fetch step 4.2
+	// chunked encoding is handled by Node.js
+
+	return Object.assign({}, parsedURL, {
+		method: request.method,
+		headers: exportNodeCompatibleHeaders(headers),
+		agent
+	});
+}
+
+/**
+ * abort-error.js
+ *
+ * AbortError interface for cancelled requests
+ */
+
+/**
+ * Create AbortError instance
+ *
+ * @param   String      message      Error message for human
+ * @return  AbortError
+ */
+function AbortError(message) {
+  Error.call(this, message);
+
+  this.type = 'aborted';
+  this.message = message;
+
+  // hide custom error implementation details from end-users
+  Error.captureStackTrace(this, this.constructor);
+}
+
+AbortError.prototype = Object.create(Error.prototype);
+AbortError.prototype.constructor = AbortError;
+AbortError.prototype.name = 'AbortError';
+
+// fix an issue where "PassThrough", "resolve" aren't a named export for node <10
+const PassThrough$1 = Stream.PassThrough;
+const resolve_url = Url.resolve;
+
+/**
+ * Fetch function
+ *
+ * @param   Mixed    url   Absolute url or Request instance
+ * @param   Object   opts  Fetch options
+ * @return  Promise
+ */
+function fetch(url, opts) {
+
+	// allow custom promise
+	if (!fetch.Promise) {
+		throw new Error('native promise missing, set fetch.Promise to your favorite alternative');
+	}
+
+	Body.Promise = fetch.Promise;
+
+	// wrap http.request into fetch
+	return new fetch.Promise(function (resolve, reject) {
+		// build request object
+		const request = new Request(url, opts);
+		const options = getNodeRequestOptions(request);
+
+		const send = (options.protocol === 'https:' ? https : http).request;
+		const signal = request.signal;
+
+		let response = null;
+
+		const abort = function abort() {
+			let error = new AbortError('The user aborted a request.');
+			reject(error);
+			if (request.body && request.body instanceof Stream.Readable) {
+				request.body.destroy(error);
+			}
+			if (!response || !response.body) return;
+			response.body.emit('error', error);
+		};
+
+		if (signal && signal.aborted) {
+			abort();
+			return;
+		}
+
+		const abortAndFinalize = function abortAndFinalize() {
+			abort();
+			finalize();
+		};
+
+		// send request
+		const req = send(options);
+		let reqTimeout;
+
+		if (signal) {
+			signal.addEventListener('abort', abortAndFinalize);
+		}
+
+		function finalize() {
+			req.abort();
+			if (signal) signal.removeEventListener('abort', abortAndFinalize);
+			clearTimeout(reqTimeout);
+		}
+
+		if (request.timeout) {
+			req.once('socket', function (socket) {
+				reqTimeout = setTimeout(function () {
+					reject(new FetchError(`network timeout at: ${request.url}`, 'request-timeout'));
+					finalize();
+				}, request.timeout);
+			});
+		}
+
+		req.on('error', function (err) {
+			reject(new FetchError(`request to ${request.url} failed, reason: ${err.message}`, 'system', err));
+			finalize();
+		});
+
+		req.on('response', function (res) {
+			clearTimeout(reqTimeout);
+
+			const headers = createHeadersLenient(res.headers);
+
+			// HTTP fetch step 5
+			if (fetch.isRedirect(res.statusCode)) {
+				// HTTP fetch step 5.2
+				const location = headers.get('Location');
+
+				// HTTP fetch step 5.3
+				const locationURL = location === null ? null : resolve_url(request.url, location);
+
+				// HTTP fetch step 5.5
+				switch (request.redirect) {
+					case 'error':
+						reject(new FetchError(`redirect mode is set to error: ${request.url}`, 'no-redirect'));
+						finalize();
+						return;
+					case 'manual':
+						// node-fetch-specific step: make manual redirect a bit easier to use by setting the Location header value to the resolved URL.
+						if (locationURL !== null) {
+							// handle corrupted header
+							try {
+								headers.set('Location', locationURL);
+							} catch (err) {
+								// istanbul ignore next: nodejs server prevent invalid response headers, we can't test this through normal request
+								reject(err);
+							}
+						}
+						break;
+					case 'follow':
+						// HTTP-redirect fetch step 2
+						if (locationURL === null) {
+							break;
+						}
+
+						// HTTP-redirect fetch step 5
+						if (request.counter >= request.follow) {
+							reject(new FetchError(`maximum redirect reached at: ${request.url}`, 'max-redirect'));
+							finalize();
+							return;
+						}
+
+						// HTTP-redirect fetch step 6 (counter increment)
+						// Create a new Request object.
+						const requestOpts = {
+							headers: new Headers(request.headers),
+							follow: request.follow,
+							counter: request.counter + 1,
+							agent: request.agent,
+							compress: request.compress,
+							method: request.method,
+							body: request.body,
+							signal: request.signal,
+							timeout: request.timeout
+						};
+
+						// HTTP-redirect fetch step 9
+						if (res.statusCode !== 303 && request.body && getTotalBytes(request) === null) {
+							reject(new FetchError('Cannot follow redirect with body being a readable stream', 'unsupported-redirect'));
+							finalize();
+							return;
+						}
+
+						// HTTP-redirect fetch step 11
+						if (res.statusCode === 303 || (res.statusCode === 301 || res.statusCode === 302) && request.method === 'POST') {
+							requestOpts.method = 'GET';
+							requestOpts.body = undefined;
+							requestOpts.headers.delete('content-length');
+						}
+
+						// HTTP-redirect fetch step 15
+						resolve(fetch(new Request(locationURL, requestOpts)));
+						finalize();
+						return;
+				}
+			}
+
+			// prepare response
+			res.once('end', function () {
+				if (signal) signal.removeEventListener('abort', abortAndFinalize);
+			});
+			let body = res.pipe(new PassThrough$1());
+
+			const response_options = {
+				url: request.url,
+				status: res.statusCode,
+				statusText: res.statusMessage,
+				headers: headers,
+				size: request.size,
+				timeout: request.timeout,
+				counter: request.counter
+			};
+
+			// HTTP-network fetch step 12.1.1.3
+			const codings = headers.get('Content-Encoding');
+
+			// HTTP-network fetch step 12.1.1.4: handle content codings
+
+			// in following scenarios we ignore compression support
+			// 1. compression support is disabled
+			// 2. HEAD request
+			// 3. no Content-Encoding header
+			// 4. no content response (204)
+			// 5. content not modified response (304)
+			if (!request.compress || request.method === 'HEAD' || codings === null || res.statusCode === 204 || res.statusCode === 304) {
+				response = new Response(body, response_options);
+				resolve(response);
+				return;
+			}
+
+			// For Node v6+
+			// Be less strict when decoding compressed responses, since sometimes
+			// servers send slightly invalid responses that are still accepted
+			// by common browsers.
+			// Always using Z_SYNC_FLUSH is what cURL does.
+			const zlibOptions = {
+				flush: zlib.Z_SYNC_FLUSH,
+				finishFlush: zlib.Z_SYNC_FLUSH
+			};
+
+			// for gzip
+			if (codings == 'gzip' || codings == 'x-gzip') {
+				body = body.pipe(zlib.createGunzip(zlibOptions));
+				response = new Response(body, response_options);
+				resolve(response);
+				return;
+			}
+
+			// for deflate
+			if (codings == 'deflate' || codings == 'x-deflate') {
+				// handle the infamous raw deflate response from old servers
+				// a hack for old IIS and Apache servers
+				const raw = res.pipe(new PassThrough$1());
+				raw.once('data', function (chunk) {
+					// see http://stackoverflow.com/questions/37519828
+					if ((chunk[0] & 0x0F) === 0x08) {
+						body = body.pipe(zlib.createInflate());
+					} else {
+						body = body.pipe(zlib.createInflateRaw());
+					}
+					response = new Response(body, response_options);
+					resolve(response);
+				});
+				return;
+			}
+
+			// for br
+			if (codings == 'br' && typeof zlib.createBrotliDecompress === 'function') {
+				body = body.pipe(zlib.createBrotliDecompress());
+				response = new Response(body, response_options);
+				resolve(response);
+				return;
+			}
+
+			// otherwise, use response as-is
+			response = new Response(body, response_options);
+			resolve(response);
+		});
+
+		writeToStream(req, request);
+	});
+}
+/**
+ * Redirect code matching
+ *
+ * @param   Number   code  Status code
+ * @return  Boolean
+ */
+fetch.isRedirect = function (code) {
+	return code === 301 || code === 302 || code === 303 || code === 307 || code === 308;
+};
+
+// expose Promise
+fetch.Promise = global.Promise;
+
+module.exports = exports = fetch;
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.default = exports;
+exports.Headers = Headers;
+exports.Request = Request;
+exports.Response = Response;
+exports.FetchError = FetchError;
diff --git a/deps/node-fetch/lib/index.mjs b/deps/node-fetch/lib/index.mjs
new file mode 100644
index 00000000000000..e571ea6964348c
--- /dev/null
+++ b/deps/node-fetch/lib/index.mjs
@@ -0,0 +1,1631 @@
+import Stream from 'stream';
+import http from 'http';
+import Url from 'url';
+import https from 'https';
+import zlib from 'zlib';
+
+// Based on https://github.com/tmpvar/jsdom/blob/aa85b2abf07766ff7bf5c1f6daafb3726f2f2db5/lib/jsdom/living/blob.js
+
+// fix for "Readable" isn't a named export issue
+const Readable = Stream.Readable;
+
+const BUFFER = Symbol('buffer');
+const TYPE = Symbol('type');
+
+class Blob {
+	constructor() {
+		this[TYPE] = '';
+
+		const blobParts = arguments[0];
+		const options = arguments[1];
+
+		const buffers = [];
+		let size = 0;
+
+		if (blobParts) {
+			const a = blobParts;
+			const length = Number(a.length);
+			for (let i = 0; i < length; i++) {
+				const element = a[i];
+				let buffer;
+				if (element instanceof Buffer) {
+					buffer = element;
+				} else if (ArrayBuffer.isView(element)) {
+					buffer = Buffer.from(element.buffer, element.byteOffset, element.byteLength);
+				} else if (element instanceof ArrayBuffer) {
+					buffer = Buffer.from(element);
+				} else if (element instanceof Blob) {
+					buffer = element[BUFFER];
+				} else {
+					buffer = Buffer.from(typeof element === 'string' ? element : String(element));
+				}
+				size += buffer.length;
+				buffers.push(buffer);
+			}
+		}
+
+		this[BUFFER] = Buffer.concat(buffers);
+
+		let type = options && options.type !== undefined && String(options.type).toLowerCase();
+		if (type && !/[^\u0020-\u007E]/.test(type)) {
+			this[TYPE] = type;
+		}
+	}
+	get size() {
+		return this[BUFFER].length;
+	}
+	get type() {
+		return this[TYPE];
+	}
+	text() {
+		return Promise.resolve(this[BUFFER].toString());
+	}
+	arrayBuffer() {
+		const buf = this[BUFFER];
+		const ab = buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength);
+		return Promise.resolve(ab);
+	}
+	stream() {
+		const readable = new Readable();
+		readable._read = function () {};
+		readable.push(this[BUFFER]);
+		readable.push(null);
+		return readable;
+	}
+	toString() {
+		return '[object Blob]';
+	}
+	slice() {
+		const size = this.size;
+
+		const start = arguments[0];
+		const end = arguments[1];
+		let relativeStart, relativeEnd;
+		if (start === undefined) {
+			relativeStart = 0;
+		} else if (start < 0) {
+			relativeStart = Math.max(size + start, 0);
+		} else {
+			relativeStart = Math.min(start, size);
+		}
+		if (end === undefined) {
+			relativeEnd = size;
+		} else if (end < 0) {
+			relativeEnd = Math.max(size + end, 0);
+		} else {
+			relativeEnd = Math.min(end, size);
+		}
+		const span = Math.max(relativeEnd - relativeStart, 0);
+
+		const buffer = this[BUFFER];
+		const slicedBuffer = buffer.slice(relativeStart, relativeStart + span);
+		const blob = new Blob([], { type: arguments[2] });
+		blob[BUFFER] = slicedBuffer;
+		return blob;
+	}
+}
+
+Object.defineProperties(Blob.prototype, {
+	size: { enumerable: true },
+	type: { enumerable: true },
+	slice: { enumerable: true }
+});
+
+Object.defineProperty(Blob.prototype, Symbol.toStringTag, {
+	value: 'Blob',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+/**
+ * fetch-error.js
+ *
+ * FetchError interface for operational errors
+ */
+
+/**
+ * Create FetchError instance
+ *
+ * @param   String      message      Error message for human
+ * @param   String      type         Error type for machine
+ * @param   String      systemError  For Node.js system error
+ * @return  FetchError
+ */
+function FetchError(message, type, systemError) {
+  Error.call(this, message);
+
+  this.message = message;
+  this.type = type;
+
+  // when err.type is `system`, err.code contains system error code
+  if (systemError) {
+    this.code = this.errno = systemError.code;
+  }
+
+  // hide custom error implementation details from end-users
+  Error.captureStackTrace(this, this.constructor);
+}
+
+FetchError.prototype = Object.create(Error.prototype);
+FetchError.prototype.constructor = FetchError;
+FetchError.prototype.name = 'FetchError';
+
+let convert;
+try {
+	convert = require('encoding').convert;
+} catch (e) {}
+
+const INTERNALS = Symbol('Body internals');
+
+// fix an issue where "PassThrough" isn't a named export for node <10
+const PassThrough = Stream.PassThrough;
+
+/**
+ * Body mixin
+ *
+ * Ref: https://fetch.spec.whatwg.org/#body
+ *
+ * @param   Stream  body  Readable stream
+ * @param   Object  opts  Response options
+ * @return  Void
+ */
+function Body(body) {
+	var _this = this;
+
+	var _ref = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {},
+	    _ref$size = _ref.size;
+
+	let size = _ref$size === undefined ? 0 : _ref$size;
+	var _ref$timeout = _ref.timeout;
+	let timeout = _ref$timeout === undefined ? 0 : _ref$timeout;
+
+	if (body == null) {
+		// body is undefined or null
+		body = null;
+	} else if (isURLSearchParams(body)) {
+		// body is a URLSearchParams
+		body = Buffer.from(body.toString());
+	} else if (isBlob(body)) ; else if (Buffer.isBuffer(body)) ; else if (Object.prototype.toString.call(body) === '[object ArrayBuffer]') {
+		// body is ArrayBuffer
+		body = Buffer.from(body);
+	} else if (ArrayBuffer.isView(body)) {
+		// body is ArrayBufferView
+		body = Buffer.from(body.buffer, body.byteOffset, body.byteLength);
+	} else if (body instanceof Stream) ; else {
+		// none of the above
+		// coerce to string then buffer
+		body = Buffer.from(String(body));
+	}
+	this[INTERNALS] = {
+		body,
+		disturbed: false,
+		error: null
+	};
+	this.size = size;
+	this.timeout = timeout;
+
+	if (body instanceof Stream) {
+		body.on('error', function (err) {
+			const error = err.name === 'AbortError' ? err : new FetchError(`Invalid response body while trying to fetch ${_this.url}: ${err.message}`, 'system', err);
+			_this[INTERNALS].error = error;
+		});
+	}
+}
+
+Body.prototype = {
+	get body() {
+		return this[INTERNALS].body;
+	},
+
+	get bodyUsed() {
+		return this[INTERNALS].disturbed;
+	},
+
+	/**
+  * Decode response as ArrayBuffer
+  *
+  * @return  Promise
+  */
+	arrayBuffer() {
+		return consumeBody.call(this).then(function (buf) {
+			return buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength);
+		});
+	},
+
+	/**
+  * Return raw response as Blob
+  *
+  * @return Promise
+  */
+	blob() {
+		let ct = this.headers && this.headers.get('content-type') || '';
+		return consumeBody.call(this).then(function (buf) {
+			return Object.assign(
+			// Prevent copying
+			new Blob([], {
+				type: ct.toLowerCase()
+			}), {
+				[BUFFER]: buf
+			});
+		});
+	},
+
+	/**
+  * Decode response as json
+  *
+  * @return  Promise
+  */
+	json() {
+		var _this2 = this;
+
+		return consumeBody.call(this).then(function (buffer) {
+			try {
+				return JSON.parse(buffer.toString());
+			} catch (err) {
+				return Body.Promise.reject(new FetchError(`invalid json response body at ${_this2.url} reason: ${err.message}`, 'invalid-json'));
+			}
+		});
+	},
+
+	/**
+  * Decode response as text
+  *
+  * @return  Promise
+  */
+	text() {
+		return consumeBody.call(this).then(function (buffer) {
+			return buffer.toString();
+		});
+	},
+
+	/**
+  * Decode response as buffer (non-spec api)
+  *
+  * @return  Promise
+  */
+	buffer() {
+		return consumeBody.call(this);
+	},
+
+	/**
+  * Decode response as text, while automatically detecting the encoding and
+  * trying to decode to UTF-8 (non-spec api)
+  *
+  * @return  Promise
+  */
+	textConverted() {
+		var _this3 = this;
+
+		return consumeBody.call(this).then(function (buffer) {
+			return convertBody(buffer, _this3.headers);
+		});
+	}
+};
+
+// In browsers, all properties are enumerable.
+Object.defineProperties(Body.prototype, {
+	body: { enumerable: true },
+	bodyUsed: { enumerable: true },
+	arrayBuffer: { enumerable: true },
+	blob: { enumerable: true },
+	json: { enumerable: true },
+	text: { enumerable: true }
+});
+
+Body.mixIn = function (proto) {
+	for (const name of Object.getOwnPropertyNames(Body.prototype)) {
+		// istanbul ignore else: future proof
+		if (!(name in proto)) {
+			const desc = Object.getOwnPropertyDescriptor(Body.prototype, name);
+			Object.defineProperty(proto, name, desc);
+		}
+	}
+};
+
+/**
+ * Consume and convert an entire Body to a Buffer.
+ *
+ * Ref: https://fetch.spec.whatwg.org/#concept-body-consume-body
+ *
+ * @return  Promise
+ */
+function consumeBody() {
+	var _this4 = this;
+
+	if (this[INTERNALS].disturbed) {
+		return Body.Promise.reject(new TypeError(`body used already for: ${this.url}`));
+	}
+
+	this[INTERNALS].disturbed = true;
+
+	if (this[INTERNALS].error) {
+		return Body.Promise.reject(this[INTERNALS].error);
+	}
+
+	let body = this.body;
+
+	// body is null
+	if (body === null) {
+		return Body.Promise.resolve(Buffer.alloc(0));
+	}
+
+	// body is blob
+	if (isBlob(body)) {
+		body = body.stream();
+	}
+
+	// body is buffer
+	if (Buffer.isBuffer(body)) {
+		return Body.Promise.resolve(body);
+	}
+
+	// istanbul ignore if: should never happen
+	if (!(body instanceof Stream)) {
+		return Body.Promise.resolve(Buffer.alloc(0));
+	}
+
+	// body is stream
+	// get ready to actually consume the body
+	let accum = [];
+	let accumBytes = 0;
+	let abort = false;
+
+	return new Body.Promise(function (resolve, reject) {
+		let resTimeout;
+
+		// allow timeout on slow response body
+		if (_this4.timeout) {
+			resTimeout = setTimeout(function () {
+				abort = true;
+				reject(new FetchError(`Response timeout while trying to fetch ${_this4.url} (over ${_this4.timeout}ms)`, 'body-timeout'));
+			}, _this4.timeout);
+		}
+
+		// handle stream errors
+		body.on('error', function (err) {
+			if (err.name === 'AbortError') {
+				// if the request was aborted, reject with this Error
+				abort = true;
+				reject(err);
+			} else {
+				// other errors, such as incorrect content-encoding
+				reject(new FetchError(`Invalid response body while trying to fetch ${_this4.url}: ${err.message}`, 'system', err));
+			}
+		});
+
+		body.on('data', function (chunk) {
+			if (abort || chunk === null) {
+				return;
+			}
+
+			if (_this4.size && accumBytes + chunk.length > _this4.size) {
+				abort = true;
+				reject(new FetchError(`content size at ${_this4.url} over limit: ${_this4.size}`, 'max-size'));
+				return;
+			}
+
+			accumBytes += chunk.length;
+			accum.push(chunk);
+		});
+
+		body.on('end', function () {
+			if (abort) {
+				return;
+			}
+
+			clearTimeout(resTimeout);
+
+			try {
+				resolve(Buffer.concat(accum, accumBytes));
+			} catch (err) {
+				// handle streams that have accumulated too much data (issue #414)
+				reject(new FetchError(`Could not create Buffer from response body for ${_this4.url}: ${err.message}`, 'system', err));
+			}
+		});
+	});
+}
+
+/**
+ * Detect buffer encoding and convert to target encoding
+ * ref: http://www.w3.org/TR/2011/WD-html5-20110113/parsing.html#determining-the-character-encoding
+ *
+ * @param   Buffer  buffer    Incoming buffer
+ * @param   String  encoding  Target encoding
+ * @return  String
+ */
+function convertBody(buffer, headers) {
+	if (typeof convert !== 'function') {
+		throw new Error('The package `encoding` must be installed to use the textConverted() function');
+	}
+
+	const ct = headers.get('content-type');
+	let charset = 'utf-8';
+	let res, str;
+
+	// header
+	if (ct) {
+		res = /charset=([^;]*)/i.exec(ct);
+	}
+
+	// no charset in content type, peek at response body for at most 1024 bytes
+	str = buffer.slice(0, 1024).toString();
+
+	// html5
+	if (!res && str) {
+		res = /<meta.+?charset=(['"])(.+?)\1/i.exec(str);
+	}
+
+	// html4
+	if (!res && str) {
+		res = /<meta[\s]+?http-equiv=(['"])content-type\1[\s]+?content=(['"])(.+?)\2/i.exec(str);
+
+		if (res) {
+			res = /charset=(.*)/i.exec(res.pop());
+		}
+	}
+
+	// xml
+	if (!res && str) {
+		res = /<\?xml.+?encoding=(['"])(.+?)\1/i.exec(str);
+	}
+
+	// found charset
+	if (res) {
+		charset = res.pop();
+
+		// prevent decode issues when sites use incorrect encoding
+		// ref: https://hsivonen.fi/encoding-menu/
+		if (charset === 'gb2312' || charset === 'gbk') {
+			charset = 'gb18030';
+		}
+	}
+
+	// turn raw buffers into a single utf-8 buffer
+	return convert(buffer, 'UTF-8', charset).toString();
+}
+
+/**
+ * Detect a URLSearchParams object
+ * ref: https://github.com/bitinn/node-fetch/issues/296#issuecomment-307598143
+ *
+ * @param   Object  obj     Object to detect by type or brand
+ * @return  String
+ */
+function isURLSearchParams(obj) {
+	// Duck-typing as a necessary condition.
+	if (typeof obj !== 'object' || typeof obj.append !== 'function' || typeof obj.delete !== 'function' || typeof obj.get !== 'function' || typeof obj.getAll !== 'function' || typeof obj.has !== 'function' || typeof obj.set !== 'function') {
+		return false;
+	}
+
+	// Brand-checking and more duck-typing as optional condition.
+	return obj.constructor.name === 'URLSearchParams' || Object.prototype.toString.call(obj) === '[object URLSearchParams]' || typeof obj.sort === 'function';
+}
+
+/**
+ * Check if `obj` is a W3C `Blob` object (which `File` inherits from)
+ * @param  {*} obj
+ * @return {boolean}
+ */
+function isBlob(obj) {
+	return typeof obj === 'object' && typeof obj.arrayBuffer === 'function' && typeof obj.type === 'string' && typeof obj.stream === 'function' && typeof obj.constructor === 'function' && typeof obj.constructor.name === 'string' && /^(Blob|File)$/.test(obj.constructor.name) && /^(Blob|File)$/.test(obj[Symbol.toStringTag]);
+}
+
+/**
+ * Clone body given Res/Req instance
+ *
+ * @param   Mixed  instance  Response or Request instance
+ * @return  Mixed
+ */
+function clone(instance) {
+	let p1, p2;
+	let body = instance.body;
+
+	// don't allow cloning a used body
+	if (instance.bodyUsed) {
+		throw new Error('cannot clone body after it is used');
+	}
+
+	// check that body is a stream and not form-data object
+	// note: we can't clone the form-data object without having it as a dependency
+	if (body instanceof Stream && typeof body.getBoundary !== 'function') {
+		// tee instance body
+		p1 = new PassThrough();
+		p2 = new PassThrough();
+		body.pipe(p1);
+		body.pipe(p2);
+		// set instance body to teed body and return the other teed body
+		instance[INTERNALS].body = p1;
+		body = p2;
+	}
+
+	return body;
+}
+
+/**
+ * Performs the operation "extract a `Content-Type` value from |object|" as
+ * specified in the specification:
+ * https://fetch.spec.whatwg.org/#concept-bodyinit-extract
+ *
+ * This function assumes that instance.body is present.
+ *
+ * @param   Mixed  instance  Any options.body input
+ */
+function extractContentType(body) {
+	if (body === null) {
+		// body is null
+		return null;
+	} else if (typeof body === 'string') {
+		// body is string
+		return 'text/plain;charset=UTF-8';
+	} else if (isURLSearchParams(body)) {
+		// body is a URLSearchParams
+		return 'application/x-www-form-urlencoded;charset=UTF-8';
+	} else if (isBlob(body)) {
+		// body is blob
+		return body.type || null;
+	} else if (Buffer.isBuffer(body)) {
+		// body is buffer
+		return null;
+	} else if (Object.prototype.toString.call(body) === '[object ArrayBuffer]') {
+		// body is ArrayBuffer
+		return null;
+	} else if (ArrayBuffer.isView(body)) {
+		// body is ArrayBufferView
+		return null;
+	} else if (typeof body.getBoundary === 'function') {
+		// detect form data input from form-data module
+		return `multipart/form-data;boundary=${body.getBoundary()}`;
+	} else if (body instanceof Stream) {
+		// body is stream
+		// can't really do much about this
+		return null;
+	} else {
+		// Body constructor defaults other things to string
+		return 'text/plain;charset=UTF-8';
+	}
+}
+
+/**
+ * The Fetch Standard treats this as if "total bytes" is a property on the body.
+ * For us, we have to explicitly get it with a function.
+ *
+ * ref: https://fetch.spec.whatwg.org/#concept-body-total-bytes
+ *
+ * @param   Body    instance   Instance of Body
+ * @return  Number?            Number of bytes, or null if not possible
+ */
+function getTotalBytes(instance) {
+	const body = instance.body;
+
+
+	if (body === null) {
+		// body is null
+		return 0;
+	} else if (isBlob(body)) {
+		return body.size;
+	} else if (Buffer.isBuffer(body)) {
+		// body is buffer
+		return body.length;
+	} else if (body && typeof body.getLengthSync === 'function') {
+		// detect form data input from form-data module
+		if (body._lengthRetrievers && body._lengthRetrievers.length == 0 || // 1.x
+		body.hasKnownLength && body.hasKnownLength()) {
+			// 2.x
+			return body.getLengthSync();
+		}
+		return null;
+	} else {
+		// body is stream
+		return null;
+	}
+}
+
+/**
+ * Write a Body to a Node.js WritableStream (e.g. http.Request) object.
+ *
+ * @param   Body    instance   Instance of Body
+ * @return  Void
+ */
+function writeToStream(dest, instance) {
+	const body = instance.body;
+
+
+	if (body === null) {
+		// body is null
+		dest.end();
+	} else if (isBlob(body)) {
+		body.stream().pipe(dest);
+	} else if (Buffer.isBuffer(body)) {
+		// body is buffer
+		dest.write(body);
+		dest.end();
+	} else {
+		// body is stream
+		body.pipe(dest);
+	}
+}
+
+// expose Promise
+Body.Promise = global.Promise;
+
+/**
+ * headers.js
+ *
+ * Headers class offers convenient helpers
+ */
+
+const invalidTokenRegex = /[^\^_`a-zA-Z\-0-9!#$%&'*+.|~]/;
+const invalidHeaderCharRegex = /[^\t\x20-\x7e\x80-\xff]/;
+
+function validateName(name) {
+	name = `${name}`;
+	if (invalidTokenRegex.test(name) || name === '') {
+		throw new TypeError(`${name} is not a legal HTTP header name`);
+	}
+}
+
+function validateValue(value) {
+	value = `${value}`;
+	if (invalidHeaderCharRegex.test(value)) {
+		throw new TypeError(`${value} is not a legal HTTP header value`);
+	}
+}
+
+/**
+ * Find the key in the map object given a header name.
+ *
+ * Returns undefined if not found.
+ *
+ * @param   String  name  Header name
+ * @return  String|Undefined
+ */
+function find(map, name) {
+	name = name.toLowerCase();
+	for (const key in map) {
+		if (key.toLowerCase() === name) {
+			return key;
+		}
+	}
+	return undefined;
+}
+
+const MAP = Symbol('map');
+class Headers {
+	/**
+  * Headers class
+  *
+  * @param   Object  headers  Response headers
+  * @return  Void
+  */
+	constructor() {
+		let init = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : undefined;
+
+		this[MAP] = Object.create(null);
+
+		if (init instanceof Headers) {
+			const rawHeaders = init.raw();
+			const headerNames = Object.keys(rawHeaders);
+
+			for (const headerName of headerNames) {
+				for (const value of rawHeaders[headerName]) {
+					this.append(headerName, value);
+				}
+			}
+
+			return;
+		}
+
+		// We don't worry about converting prop to ByteString here as append()
+		// will handle it.
+		if (init == null) ; else if (typeof init === 'object') {
+			const method = init[Symbol.iterator];
+			if (method != null) {
+				if (typeof method !== 'function') {
+					throw new TypeError('Header pairs must be iterable');
+				}
+
+				// sequence<sequence<ByteString>>
+				// Note: per spec we have to first exhaust the lists then process them
+				const pairs = [];
+				for (const pair of init) {
+					if (typeof pair !== 'object' || typeof pair[Symbol.iterator] !== 'function') {
+						throw new TypeError('Each header pair must be iterable');
+					}
+					pairs.push(Array.from(pair));
+				}
+
+				for (const pair of pairs) {
+					if (pair.length !== 2) {
+						throw new TypeError('Each header pair must be a name/value tuple');
+					}
+					this.append(pair[0], pair[1]);
+				}
+			} else {
+				// record<ByteString, ByteString>
+				for (const key of Object.keys(init)) {
+					const value = init[key];
+					this.append(key, value);
+				}
+			}
+		} else {
+			throw new TypeError('Provided initializer must be an object');
+		}
+	}
+
+	/**
+  * Return combined header value given name
+  *
+  * @param   String  name  Header name
+  * @return  Mixed
+  */
+	get(name) {
+		name = `${name}`;
+		validateName(name);
+		const key = find(this[MAP], name);
+		if (key === undefined) {
+			return null;
+		}
+
+		return this[MAP][key].join(', ');
+	}
+
+	/**
+  * Iterate over all headers
+  *
+  * @param   Function  callback  Executed for each item with parameters (value, name, thisArg)
+  * @param   Boolean   thisArg   `this` context for callback function
+  * @return  Void
+  */
+	forEach(callback) {
+		let thisArg = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : undefined;
+
+		let pairs = getHeaders(this);
+		let i = 0;
+		while (i < pairs.length) {
+			var _pairs$i = pairs[i];
+			const name = _pairs$i[0],
+			      value = _pairs$i[1];
+
+			callback.call(thisArg, value, name, this);
+			pairs = getHeaders(this);
+			i++;
+		}
+	}
+
+	/**
+  * Overwrite header values given name
+  *
+  * @param   String  name   Header name
+  * @param   String  value  Header value
+  * @return  Void
+  */
+	set(name, value) {
+		name = `${name}`;
+		value = `${value}`;
+		validateName(name);
+		validateValue(value);
+		const key = find(this[MAP], name);
+		this[MAP][key !== undefined ? key : name] = [value];
+	}
+
+	/**
+  * Append a value onto existing header
+  *
+  * @param   String  name   Header name
+  * @param   String  value  Header value
+  * @return  Void
+  */
+	append(name, value) {
+		name = `${name}`;
+		value = `${value}`;
+		validateName(name);
+		validateValue(value);
+		const key = find(this[MAP], name);
+		if (key !== undefined) {
+			this[MAP][key].push(value);
+		} else {
+			this[MAP][name] = [value];
+		}
+	}
+
+	/**
+  * Check for header name existence
+  *
+  * @param   String   name  Header name
+  * @return  Boolean
+  */
+	has(name) {
+		name = `${name}`;
+		validateName(name);
+		return find(this[MAP], name) !== undefined;
+	}
+
+	/**
+  * Delete all header values given name
+  *
+  * @param   String  name  Header name
+  * @return  Void
+  */
+	delete(name) {
+		name = `${name}`;
+		validateName(name);
+		const key = find(this[MAP], name);
+		if (key !== undefined) {
+			delete this[MAP][key];
+		}
+	}
+
+	/**
+  * Return raw headers (non-spec api)
+  *
+  * @return  Object
+  */
+	raw() {
+		return this[MAP];
+	}
+
+	/**
+  * Get an iterator on keys.
+  *
+  * @return  Iterator
+  */
+	keys() {
+		return createHeadersIterator(this, 'key');
+	}
+
+	/**
+  * Get an iterator on values.
+  *
+  * @return  Iterator
+  */
+	values() {
+		return createHeadersIterator(this, 'value');
+	}
+
+	/**
+  * Get an iterator on entries.
+  *
+  * This is the default iterator of the Headers object.
+  *
+  * @return  Iterator
+  */
+	[Symbol.iterator]() {
+		return createHeadersIterator(this, 'key+value');
+	}
+}
+Headers.prototype.entries = Headers.prototype[Symbol.iterator];
+
+Object.defineProperty(Headers.prototype, Symbol.toStringTag, {
+	value: 'Headers',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+Object.defineProperties(Headers.prototype, {
+	get: { enumerable: true },
+	forEach: { enumerable: true },
+	set: { enumerable: true },
+	append: { enumerable: true },
+	has: { enumerable: true },
+	delete: { enumerable: true },
+	keys: { enumerable: true },
+	values: { enumerable: true },
+	entries: { enumerable: true }
+});
+
+function getHeaders(headers) {
+	let kind = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 'key+value';
+
+	const keys = Object.keys(headers[MAP]).sort();
+	return keys.map(kind === 'key' ? function (k) {
+		return k.toLowerCase();
+	} : kind === 'value' ? function (k) {
+		return headers[MAP][k].join(', ');
+	} : function (k) {
+		return [k.toLowerCase(), headers[MAP][k].join(', ')];
+	});
+}
+
+const INTERNAL = Symbol('internal');
+
+function createHeadersIterator(target, kind) {
+	const iterator = Object.create(HeadersIteratorPrototype);
+	iterator[INTERNAL] = {
+		target,
+		kind,
+		index: 0
+	};
+	return iterator;
+}
+
+const HeadersIteratorPrototype = Object.setPrototypeOf({
+	next() {
+		// istanbul ignore if
+		if (!this || Object.getPrototypeOf(this) !== HeadersIteratorPrototype) {
+			throw new TypeError('Value of `this` is not a HeadersIterator');
+		}
+
+		var _INTERNAL = this[INTERNAL];
+		const target = _INTERNAL.target,
+		      kind = _INTERNAL.kind,
+		      index = _INTERNAL.index;
+
+		const values = getHeaders(target, kind);
+		const len = values.length;
+		if (index >= len) {
+			return {
+				value: undefined,
+				done: true
+			};
+		}
+
+		this[INTERNAL].index = index + 1;
+
+		return {
+			value: values[index],
+			done: false
+		};
+	}
+}, Object.getPrototypeOf(Object.getPrototypeOf([][Symbol.iterator]())));
+
+Object.defineProperty(HeadersIteratorPrototype, Symbol.toStringTag, {
+	value: 'HeadersIterator',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+/**
+ * Export the Headers object in a form that Node.js can consume.
+ *
+ * @param   Headers  headers
+ * @return  Object
+ */
+function exportNodeCompatibleHeaders(headers) {
+	const obj = Object.assign({ __proto__: null }, headers[MAP]);
+
+	// http.request() only supports string as Host header. This hack makes
+	// specifying custom Host header possible.
+	const hostHeaderKey = find(headers[MAP], 'Host');
+	if (hostHeaderKey !== undefined) {
+		obj[hostHeaderKey] = obj[hostHeaderKey][0];
+	}
+
+	return obj;
+}
+
+/**
+ * Create a Headers object from an object of headers, ignoring those that do
+ * not conform to HTTP grammar productions.
+ *
+ * @param   Object  obj  Object of headers
+ * @return  Headers
+ */
+function createHeadersLenient(obj) {
+	const headers = new Headers();
+	for (const name of Object.keys(obj)) {
+		if (invalidTokenRegex.test(name)) {
+			continue;
+		}
+		if (Array.isArray(obj[name])) {
+			for (const val of obj[name]) {
+				if (invalidHeaderCharRegex.test(val)) {
+					continue;
+				}
+				if (headers[MAP][name] === undefined) {
+					headers[MAP][name] = [val];
+				} else {
+					headers[MAP][name].push(val);
+				}
+			}
+		} else if (!invalidHeaderCharRegex.test(obj[name])) {
+			headers[MAP][name] = [obj[name]];
+		}
+	}
+	return headers;
+}
+
+const INTERNALS$1 = Symbol('Response internals');
+
+// fix an issue where "STATUS_CODES" aren't a named export for node <10
+const STATUS_CODES = http.STATUS_CODES;
+
+/**
+ * Response class
+ *
+ * @param   Stream  body  Readable stream
+ * @param   Object  opts  Response options
+ * @return  Void
+ */
+class Response {
+	constructor() {
+		let body = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : null;
+		let opts = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
+
+		Body.call(this, body, opts);
+
+		const status = opts.status || 200;
+		const headers = new Headers(opts.headers);
+
+		if (body != null && !headers.has('Content-Type')) {
+			const contentType = extractContentType(body);
+			if (contentType) {
+				headers.append('Content-Type', contentType);
+			}
+		}
+
+		this[INTERNALS$1] = {
+			url: opts.url,
+			status,
+			statusText: opts.statusText || STATUS_CODES[status],
+			headers,
+			counter: opts.counter
+		};
+	}
+
+	get url() {
+		return this[INTERNALS$1].url || '';
+	}
+
+	get status() {
+		return this[INTERNALS$1].status;
+	}
+
+	/**
+  * Convenience property representing if the request ended normally
+  */
+	get ok() {
+		return this[INTERNALS$1].status >= 200 && this[INTERNALS$1].status < 300;
+	}
+
+	get redirected() {
+		return this[INTERNALS$1].counter > 0;
+	}
+
+	get statusText() {
+		return this[INTERNALS$1].statusText;
+	}
+
+	get headers() {
+		return this[INTERNALS$1].headers;
+	}
+
+	/**
+  * Clone this response
+  *
+  * @return  Response
+  */
+	clone() {
+		return new Response(clone(this), {
+			url: this.url,
+			status: this.status,
+			statusText: this.statusText,
+			headers: this.headers,
+			ok: this.ok,
+			redirected: this.redirected
+		});
+	}
+}
+
+Body.mixIn(Response.prototype);
+
+Object.defineProperties(Response.prototype, {
+	url: { enumerable: true },
+	status: { enumerable: true },
+	ok: { enumerable: true },
+	redirected: { enumerable: true },
+	statusText: { enumerable: true },
+	headers: { enumerable: true },
+	clone: { enumerable: true }
+});
+
+Object.defineProperty(Response.prototype, Symbol.toStringTag, {
+	value: 'Response',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+const INTERNALS$2 = Symbol('Request internals');
+
+// fix an issue where "format", "parse" aren't a named export for node <10
+const parse_url = Url.parse;
+const format_url = Url.format;
+
+const streamDestructionSupported = 'destroy' in Stream.Readable.prototype;
+
+/**
+ * Check if a value is an instance of Request.
+ *
+ * @param   Mixed   input
+ * @return  Boolean
+ */
+function isRequest(input) {
+	return typeof input === 'object' && typeof input[INTERNALS$2] === 'object';
+}
+
+function isAbortSignal(signal) {
+	const proto = signal && typeof signal === 'object' && Object.getPrototypeOf(signal);
+	return !!(proto && proto.constructor.name === 'AbortSignal');
+}
+
+/**
+ * Request class
+ *
+ * @param   Mixed   input  Url or Request instance
+ * @param   Object  init   Custom options
+ * @return  Void
+ */
+class Request {
+	constructor(input) {
+		let init = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
+
+		let parsedURL;
+
+		// normalize input
+		if (!isRequest(input)) {
+			if (input && input.href) {
+				// in order to support Node.js' Url objects; though WHATWG's URL objects
+				// will fall into this branch also (since their `toString()` will return
+				// `href` property anyway)
+				parsedURL = parse_url(input.href);
+			} else {
+				// coerce input to a string before attempting to parse
+				parsedURL = parse_url(`${input}`);
+			}
+			input = {};
+		} else {
+			parsedURL = parse_url(input.url);
+		}
+
+		let method = init.method || input.method || 'GET';
+		method = method.toUpperCase();
+
+		if ((init.body != null || isRequest(input) && input.body !== null) && (method === 'GET' || method === 'HEAD')) {
+			throw new TypeError('Request with GET/HEAD method cannot have body');
+		}
+
+		let inputBody = init.body != null ? init.body : isRequest(input) && input.body !== null ? clone(input) : null;
+
+		Body.call(this, inputBody, {
+			timeout: init.timeout || input.timeout || 0,
+			size: init.size || input.size || 0
+		});
+
+		const headers = new Headers(init.headers || input.headers || {});
+
+		if (inputBody != null && !headers.has('Content-Type')) {
+			const contentType = extractContentType(inputBody);
+			if (contentType) {
+				headers.append('Content-Type', contentType);
+			}
+		}
+
+		let signal = isRequest(input) ? input.signal : null;
+		if ('signal' in init) signal = init.signal;
+
+		if (signal != null && !isAbortSignal(signal)) {
+			throw new TypeError('Expected signal to be an instanceof AbortSignal');
+		}
+
+		this[INTERNALS$2] = {
+			method,
+			redirect: init.redirect || input.redirect || 'follow',
+			headers,
+			parsedURL,
+			signal
+		};
+
+		// node-fetch-only options
+		this.follow = init.follow !== undefined ? init.follow : input.follow !== undefined ? input.follow : 20;
+		this.compress = init.compress !== undefined ? init.compress : input.compress !== undefined ? input.compress : true;
+		this.counter = init.counter || input.counter || 0;
+		this.agent = init.agent || input.agent;
+	}
+
+	get method() {
+		return this[INTERNALS$2].method;
+	}
+
+	get url() {
+		return format_url(this[INTERNALS$2].parsedURL);
+	}
+
+	get headers() {
+		return this[INTERNALS$2].headers;
+	}
+
+	get redirect() {
+		return this[INTERNALS$2].redirect;
+	}
+
+	get signal() {
+		return this[INTERNALS$2].signal;
+	}
+
+	/**
+  * Clone this request
+  *
+  * @return  Request
+  */
+	clone() {
+		return new Request(this);
+	}
+}
+
+Body.mixIn(Request.prototype);
+
+Object.defineProperty(Request.prototype, Symbol.toStringTag, {
+	value: 'Request',
+	writable: false,
+	enumerable: false,
+	configurable: true
+});
+
+Object.defineProperties(Request.prototype, {
+	method: { enumerable: true },
+	url: { enumerable: true },
+	headers: { enumerable: true },
+	redirect: { enumerable: true },
+	clone: { enumerable: true },
+	signal: { enumerable: true }
+});
+
+/**
+ * Convert a Request to Node.js http request options.
+ *
+ * @param   Request  A Request instance
+ * @return  Object   The options object to be passed to http.request
+ */
+function getNodeRequestOptions(request) {
+	const parsedURL = request[INTERNALS$2].parsedURL;
+	const headers = new Headers(request[INTERNALS$2].headers);
+
+	// fetch step 1.3
+	if (!headers.has('Accept')) {
+		headers.set('Accept', '*/*');
+	}
+
+	// Basic fetch
+	if (!parsedURL.protocol || !parsedURL.hostname) {
+		throw new TypeError('Only absolute URLs are supported');
+	}
+
+	if (!/^https?:$/.test(parsedURL.protocol)) {
+		throw new TypeError('Only HTTP(S) protocols are supported');
+	}
+
+	if (request.signal && request.body instanceof Stream.Readable && !streamDestructionSupported) {
+		throw new Error('Cancellation of streamed requests with AbortSignal is not supported in node < 8');
+	}
+
+	// HTTP-network-or-cache fetch steps 2.4-2.7
+	let contentLengthValue = null;
+	if (request.body == null && /^(POST|PUT)$/i.test(request.method)) {
+		contentLengthValue = '0';
+	}
+	if (request.body != null) {
+		const totalBytes = getTotalBytes(request);
+		if (typeof totalBytes === 'number') {
+			contentLengthValue = String(totalBytes);
+		}
+	}
+	if (contentLengthValue) {
+		headers.set('Content-Length', contentLengthValue);
+	}
+
+	// HTTP-network-or-cache fetch step 2.11
+	if (!headers.has('User-Agent')) {
+		headers.set('User-Agent', 'node-fetch/1.0 (+https://github.com/bitinn/node-fetch)');
+	}
+
+	// HTTP-network-or-cache fetch step 2.15
+	if (request.compress && !headers.has('Accept-Encoding')) {
+		headers.set('Accept-Encoding', 'gzip,deflate');
+	}
+
+	let agent = request.agent;
+	if (typeof agent === 'function') {
+		agent = agent(parsedURL);
+	}
+
+	if (!headers.has('Connection') && !agent) {
+		headers.set('Connection', 'close');
+	}
+
+	// HTTP-network fetch step 4.2
+	// chunked encoding is handled by Node.js
+
+	return Object.assign({}, parsedURL, {
+		method: request.method,
+		headers: exportNodeCompatibleHeaders(headers),
+		agent
+	});
+}
+
+/**
+ * abort-error.js
+ *
+ * AbortError interface for cancelled requests
+ */
+
+/**
+ * Create AbortError instance
+ *
+ * @param   String      message      Error message for human
+ * @return  AbortError
+ */
+function AbortError(message) {
+  Error.call(this, message);
+
+  this.type = 'aborted';
+  this.message = message;
+
+  // hide custom error implementation details from end-users
+  Error.captureStackTrace(this, this.constructor);
+}
+
+AbortError.prototype = Object.create(Error.prototype);
+AbortError.prototype.constructor = AbortError;
+AbortError.prototype.name = 'AbortError';
+
+// fix an issue where "PassThrough", "resolve" aren't a named export for node <10
+const PassThrough$1 = Stream.PassThrough;
+const resolve_url = Url.resolve;
+
+/**
+ * Fetch function
+ *
+ * @param   Mixed    url   Absolute url or Request instance
+ * @param   Object   opts  Fetch options
+ * @return  Promise
+ */
+function fetch(url, opts) {
+
+	// allow custom promise
+	if (!fetch.Promise) {
+		throw new Error('native promise missing, set fetch.Promise to your favorite alternative');
+	}
+
+	Body.Promise = fetch.Promise;
+
+	// wrap http.request into fetch
+	return new fetch.Promise(function (resolve, reject) {
+		// build request object
+		const request = new Request(url, opts);
+		const options = getNodeRequestOptions(request);
+
+		const send = (options.protocol === 'https:' ? https : http).request;
+		const signal = request.signal;
+
+		let response = null;
+
+		const abort = function abort() {
+			let error = new AbortError('The user aborted a request.');
+			reject(error);
+			if (request.body && request.body instanceof Stream.Readable) {
+				request.body.destroy(error);
+			}
+			if (!response || !response.body) return;
+			response.body.emit('error', error);
+		};
+
+		if (signal && signal.aborted) {
+			abort();
+			return;
+		}
+
+		const abortAndFinalize = function abortAndFinalize() {
+			abort();
+			finalize();
+		};
+
+		// send request
+		const req = send(options);
+		let reqTimeout;
+
+		if (signal) {
+			signal.addEventListener('abort', abortAndFinalize);
+		}
+
+		function finalize() {
+			req.abort();
+			if (signal) signal.removeEventListener('abort', abortAndFinalize);
+			clearTimeout(reqTimeout);
+		}
+
+		if (request.timeout) {
+			req.once('socket', function (socket) {
+				reqTimeout = setTimeout(function () {
+					reject(new FetchError(`network timeout at: ${request.url}`, 'request-timeout'));
+					finalize();
+				}, request.timeout);
+			});
+		}
+
+		req.on('error', function (err) {
+			reject(new FetchError(`request to ${request.url} failed, reason: ${err.message}`, 'system', err));
+			finalize();
+		});
+
+		req.on('response', function (res) {
+			clearTimeout(reqTimeout);
+
+			const headers = createHeadersLenient(res.headers);
+
+			// HTTP fetch step 5
+			if (fetch.isRedirect(res.statusCode)) {
+				// HTTP fetch step 5.2
+				const location = headers.get('Location');
+
+				// HTTP fetch step 5.3
+				const locationURL = location === null ? null : resolve_url(request.url, location);
+
+				// HTTP fetch step 5.5
+				switch (request.redirect) {
+					case 'error':
+						reject(new FetchError(`redirect mode is set to error: ${request.url}`, 'no-redirect'));
+						finalize();
+						return;
+					case 'manual':
+						// node-fetch-specific step: make manual redirect a bit easier to use by setting the Location header value to the resolved URL.
+						if (locationURL !== null) {
+							// handle corrupted header
+							try {
+								headers.set('Location', locationURL);
+							} catch (err) {
+								// istanbul ignore next: nodejs server prevent invalid response headers, we can't test this through normal request
+								reject(err);
+							}
+						}
+						break;
+					case 'follow':
+						// HTTP-redirect fetch step 2
+						if (locationURL === null) {
+							break;
+						}
+
+						// HTTP-redirect fetch step 5
+						if (request.counter >= request.follow) {
+							reject(new FetchError(`maximum redirect reached at: ${request.url}`, 'max-redirect'));
+							finalize();
+							return;
+						}
+
+						// HTTP-redirect fetch step 6 (counter increment)
+						// Create a new Request object.
+						const requestOpts = {
+							headers: new Headers(request.headers),
+							follow: request.follow,
+							counter: request.counter + 1,
+							agent: request.agent,
+							compress: request.compress,
+							method: request.method,
+							body: request.body,
+							signal: request.signal,
+							timeout: request.timeout
+						};
+
+						// HTTP-redirect fetch step 9
+						if (res.statusCode !== 303 && request.body && getTotalBytes(request) === null) {
+							reject(new FetchError('Cannot follow redirect with body being a readable stream', 'unsupported-redirect'));
+							finalize();
+							return;
+						}
+
+						// HTTP-redirect fetch step 11
+						if (res.statusCode === 303 || (res.statusCode === 301 || res.statusCode === 302) && request.method === 'POST') {
+							requestOpts.method = 'GET';
+							requestOpts.body = undefined;
+							requestOpts.headers.delete('content-length');
+						}
+
+						// HTTP-redirect fetch step 15
+						resolve(fetch(new Request(locationURL, requestOpts)));
+						finalize();
+						return;
+				}
+			}
+
+			// prepare response
+			res.once('end', function () {
+				if (signal) signal.removeEventListener('abort', abortAndFinalize);
+			});
+			let body = res.pipe(new PassThrough$1());
+
+			const response_options = {
+				url: request.url,
+				status: res.statusCode,
+				statusText: res.statusMessage,
+				headers: headers,
+				size: request.size,
+				timeout: request.timeout,
+				counter: request.counter
+			};
+
+			// HTTP-network fetch step 12.1.1.3
+			const codings = headers.get('Content-Encoding');
+
+			// HTTP-network fetch step 12.1.1.4: handle content codings
+
+			// in following scenarios we ignore compression support
+			// 1. compression support is disabled
+			// 2. HEAD request
+			// 3. no Content-Encoding header
+			// 4. no content response (204)
+			// 5. content not modified response (304)
+			if (!request.compress || request.method === 'HEAD' || codings === null || res.statusCode === 204 || res.statusCode === 304) {
+				response = new Response(body, response_options);
+				resolve(response);
+				return;
+			}
+
+			// For Node v6+
+			// Be less strict when decoding compressed responses, since sometimes
+			// servers send slightly invalid responses that are still accepted
+			// by common browsers.
+			// Always using Z_SYNC_FLUSH is what cURL does.
+			const zlibOptions = {
+				flush: zlib.Z_SYNC_FLUSH,
+				finishFlush: zlib.Z_SYNC_FLUSH
+			};
+
+			// for gzip
+			if (codings == 'gzip' || codings == 'x-gzip') {
+				body = body.pipe(zlib.createGunzip(zlibOptions));
+				response = new Response(body, response_options);
+				resolve(response);
+				return;
+			}
+
+			// for deflate
+			if (codings == 'deflate' || codings == 'x-deflate') {
+				// handle the infamous raw deflate response from old servers
+				// a hack for old IIS and Apache servers
+				const raw = res.pipe(new PassThrough$1());
+				raw.once('data', function (chunk) {
+					// see http://stackoverflow.com/questions/37519828
+					if ((chunk[0] & 0x0F) === 0x08) {
+						body = body.pipe(zlib.createInflate());
+					} else {
+						body = body.pipe(zlib.createInflateRaw());
+					}
+					response = new Response(body, response_options);
+					resolve(response);
+				});
+				return;
+			}
+
+			// for br
+			if (codings == 'br' && typeof zlib.createBrotliDecompress === 'function') {
+				body = body.pipe(zlib.createBrotliDecompress());
+				response = new Response(body, response_options);
+				resolve(response);
+				return;
+			}
+
+			// otherwise, use response as-is
+			response = new Response(body, response_options);
+			resolve(response);
+		});
+
+		writeToStream(req, request);
+	});
+}
+/**
+ * Redirect code matching
+ *
+ * @param   Number   code  Status code
+ * @return  Boolean
+ */
+fetch.isRedirect = function (code) {
+	return code === 301 || code === 302 || code === 303 || code === 307 || code === 308;
+};
+
+// expose Promise
+fetch.Promise = global.Promise;
+
+export default fetch;
+export { Headers, Request, Response, FetchError };
diff --git a/deps/node-fetch/package.json b/deps/node-fetch/package.json
new file mode 100644
index 00000000000000..9fac99c624e741
--- /dev/null
+++ b/deps/node-fetch/package.json
@@ -0,0 +1,70 @@
+{
+  "author": {
+    "name": "David Frank"
+  },
+  "browser": "./browser.js",
+  "bugs": {
+    "url": "https://github.com/bitinn/node-fetch/issues"
+  },
+  "bundleDependencies": false,
+  "dependencies": {},
+  "deprecated": false,
+  "description": "A light-weight module that brings window.fetch to node.js",
+  "devDependencies": {
+    "@ungap/url-search-params": "^0.1.2",
+    "abort-controller": "^1.1.0",
+    "abortcontroller-polyfill": "^1.3.0",
+    "babel-core": "^6.26.3",
+    "babel-plugin-istanbul": "^4.1.6",
+    "babel-preset-env": "^1.6.1",
+    "babel-register": "^6.16.3",
+    "chai": "^3.5.0",
+    "chai-as-promised": "^7.1.1",
+    "chai-iterator": "^1.1.1",
+    "chai-string": "~1.3.0",
+    "codecov": "^3.3.0",
+    "cross-env": "^5.2.0",
+    "form-data": "^2.3.3",
+    "is-builtin-module": "^1.0.0",
+    "mocha": "^5.0.0",
+    "nyc": "11.9.0",
+    "parted": "^0.1.1",
+    "promise": "^8.0.3",
+    "resumer": "0.0.0",
+    "rollup": "^0.63.4",
+    "rollup-plugin-babel": "^3.0.7",
+    "string-to-arraybuffer": "^1.0.2",
+    "whatwg-url": "^5.0.0"
+  },
+  "engines": {
+    "node": "4.x || >=6.0.0"
+  },
+  "files": [
+    "lib/index.js",
+    "lib/index.mjs",
+    "lib/index.es.js",
+    "browser.js"
+  ],
+  "homepage": "https://github.com/bitinn/node-fetch",
+  "keywords": [
+    "fetch",
+    "http",
+    "promise"
+  ],
+  "license": "MIT",
+  "main": "lib/index",
+  "module": "lib/index.mjs",
+  "name": "node-fetch",
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/bitinn/node-fetch.git"
+  },
+  "scripts": {
+    "build": "cross-env BABEL_ENV=rollup rollup -c",
+    "coverage": "cross-env BABEL_ENV=coverage nyc --reporter json --reporter text mocha -R spec test/test.js && codecov -f coverage/coverage-final.json",
+    "prepare": "npm run build",
+    "report": "cross-env BABEL_ENV=coverage nyc --reporter lcov --reporter text mocha -R spec test/test.js",
+    "test": "cross-env BABEL_ENV=test mocha --require babel-register --throw-deprecation test/test.js"
+  },
+  "version": "2.6.0"
+}
\ No newline at end of file
diff --git a/lib/http.js b/lib/http.js
index 8582557446397e..4e7d45185b7849 100644
--- a/lib/http.js
+++ b/lib/http.js
@@ -34,6 +34,7 @@ const {
   Server,
   ServerResponse
 } = require('_http_server');
+const { getOptionValue } = require('internal/options');
 let maxHeaderSize;
 
 function createServer(opts, requestListener) {
@@ -88,3 +89,14 @@ Object.defineProperty(module.exports, 'globalAgent', {
     httpAgent.globalAgent = value;
   }
 });
+
+if (getOptionValue('--experimental-fetch')) {
+  const fetch = require('internal/fetch');
+  // https://url.spec.whatwg.org/#fetch
+  Object.defineProperty(module.exports, 'fetch', {
+    writable: true,
+    enumerable: false,
+    configurable: true,
+    value: fetch
+  });
+}
diff --git a/lib/internal/fetch.js b/lib/internal/fetch.js
new file mode 100644
index 00000000000000..4965058ac9a17c
--- /dev/null
+++ b/lib/internal/fetch.js
@@ -0,0 +1,3 @@
+'use strict';
+
+module.exports = require('internal/deps/node-fetch/lib/index');
diff --git a/node.gyp b/node.gyp
index 091fe0470c4802..3ba82a42d08c46 100644
--- a/node.gyp
+++ b/node.gyp
@@ -30,6 +30,7 @@
       'lib/internal/bootstrap/loaders.js',
       'lib/internal/bootstrap/node.js',
       'lib/internal/bootstrap/pre_execution.js',
+      'lib/internal/fetch.js',
       'lib/internal/per_context/primordials.js',
       'lib/internal/per_context/setup.js',
       'lib/internal/per_context/domexception.js',
@@ -229,6 +230,7 @@
       'deps/acorn-plugins/acorn-private-class-elements/index.js',
       'deps/acorn-plugins/acorn-private-methods/index.js',
       'deps/acorn-plugins/acorn-static-class-features/index.js',
+      'deps/node-fetch/lib/index.js',
     ],
     'node_mksnapshot_exec': '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)node_mksnapshot<(EXECUTABLE_SUFFIX)',
     'mkcodecache_exec': '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)mkcodecache<(EXECUTABLE_SUFFIX)',
diff --git a/src/node_options.cc b/src/node_options.cc
index da7a49231fcb91..30aa772f105192 100644
--- a/src/node_options.cc
+++ b/src/node_options.cc
@@ -279,6 +279,10 @@ DebugOptionsParser::DebugOptionsParser() {
 }
 
 EnvironmentOptionsParser::EnvironmentOptionsParser() {
+  AddOption("--experimental-fetch",
+            "experimental WHATWG fetch support",
+            &EnvironmentOptions::experimental_fetch,
+            kAllowedInEnvironment);
   AddOption("--experimental-modules",
             "experimental ES Module support and caching modules",
             &EnvironmentOptions::experimental_modules,
diff --git a/src/node_options.h b/src/node_options.h
index 6b4eb89a9698a1..79102a1bdf8d92 100644
--- a/src/node_options.h
+++ b/src/node_options.h
@@ -91,6 +91,7 @@ class DebugOptions : public Options {
 class EnvironmentOptions : public Options {
  public:
   bool abort_on_uncaught_exception = false;
+  bool experimental_fetch = false;
   bool experimental_modules = false;
   std::string es_module_specifier_resolution;
   bool experimental_wasm_modules = false;
diff --git a/test/parallel/test-http-fetch.js b/test/parallel/test-http-fetch.js
new file mode 100644
index 00000000000000..cd6199e86e8ae9
--- /dev/null
+++ b/test/parallel/test-http-fetch.js
@@ -0,0 +1,24 @@
+// Flags: --experimental-fetch
+
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+const {fetch, Server} = require('http');
+
+const server = Server(common.mustCall((req, res) => {
+  res.writeHead(200, { 'Content-Type': 'text/plain' });
+  res.write('oh hi');
+  res.end();
+}));
+server.listen(0);
+
+server.on('listening', async () => {
+  const port = server.address().port;
+  const p = fetch(`http://localhost:${port}`);
+  assert(p instanceof fetch.Promise);
+  assert(p.then);
+  const res = await p;
+  const text = await res.text();
+  assert.strictEqual(text, 'oh hi');
+  server.close();
+});
diff --git a/tools/license-builder.sh b/tools/license-builder.sh
index d4c39203884df3..c116318b97c91b 100755
--- a/tools/license-builder.sh
+++ b/tools/license-builder.sh
@@ -106,4 +106,6 @@ addlicense "HdrHistogram" "deps/histogram" "$(cat ${rootdir}/deps/histogram/LICE
 addlicense "node-heapdump" "src/heap_utils.cc" \
            "$(curl -sL https://raw.githubusercontent.com/bnoordhuis/node-heapdump/0ca52441e46241ffbea56a389e2856ec01c48c97/LICENSE)"
 
+addlicense "node-fetch" "deps/node-fetch" "$(cat ${rootdir}/deps/node-fetch/LICENSE.md)"
+
 mv $tmplicense $licensefile
diff --git a/tools/update-node-fetch.sh b/tools/update-node-fetch.sh
new file mode 100755
index 00000000000000..812b4d80f0d7c1
--- /dev/null
+++ b/tools/update-node-fetch.sh
@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+
+# Shell script to update node-fetch in the source tree to the latest release.
+
+# Depends on npm, npx, and node being in $PATH.
+
+# This script must be be in the tools directory when it runs because it uses
+# $BASH_SOURCE[0] to determine directories to work in.
+
+cd "$( dirname "${BASH_SOURCE[0]}" )"
+rm -rf ../deps/node-fetch
+mkdir node-fetch-tmp
+cd node-fetch-tmp
+npm init --yes
+
+npm install --global-style --no-bin-links --production --no-package-lock node-fetch@latest
+cd node_modules/node-fetch
+
+# Use dmn to remove some unneeded files.
+npx dmn@2.2.2 -f clean
+# Use removeNPMAbsolutePaths to remove unused data in package.json.
+# This avoids churn as absolute paths can change from one dev to another.
+npx removeNPMAbsolutePaths@1.0.4 .
+
+cd ../../..
+mv node-fetch-tmp/node_modules/node-fetch ../deps/node-fetch
+rm -rf node-fetch-tmp/