validate schema against meta-schema

Author: epoberezkin

README.md

@@ -58,7 +58,7 @@ or
 // ...
 ajv.addSchema(schema, 'mySchema');
 var valid = ajv.validate('mySchema', data);
-if (!valid) console.log(ajv.errors);
+if (!valid) console.log(ajv.errorsText());
 // ...
 ```
 
@@ -80,6 +80,8 @@ Generate validating function and cache the compiled schema for future use.
 
 Validating function returns boolean and has properties `errors` with the errors from the last validation (`null` if there were no errors) and `schema` with the reference to the original schema. 
 
+Unless options `validateSchema` is false, the schema will be validated against meta-schema and if schema is invalid the errors will be logged. See [options](#options).
+
 
 ##### .validate(Object schema|String key|String ref, data) -> Boolean
 
@@ -120,13 +122,22 @@ Function should return validation result as `true` or `false`.
 Custom formats can be also added via `formats` option.
 
 
+##### .errorsText([Array<Object> errors [, Object options]]) -&gt; String
+
+Returns the text with all errors in a String. Options can have these properties:
+
+- separator: string used to separate errors, ", " is used by default.
+- dataVar: the variable name that dataPaths are prefixed with, "data" by default.
+
+
 ## Options
 
 - _allErrors_: check all rules collecting all errors. Default is to return after the first error.
 - _verbose_: include the reference to the part of the schema and validated data in errors (false by default).
 - _format_: formats validation mode ('fast' by default). Pass 'full' for more correct and slow validation or `false` not to validate formats at all. E.g., 25:00:00 and 2015/14/33 will be invalid time and date in 'full' mode but it will be valid in 'fast' mode.
 - _formats_: an object with custom formats. Keys and values will be passed to `addFormat` method.
 - _meta_: add [meta-schema](http://json-schema.org/documentation.html) so it can be used by other schemas (true by default).
+- _validateSchema: validate schema against meta-schema (true by default). `$schema` property in the schema can either be absent (draft-4 meta-schema will be used) or can be a reference to any previously added schema. If the validation fails, the errors will be logged.
 - _uniqueItems_: validate `uniqueItems` keyword (true by default).
 - _unicode_: calculate correct length of strings with unicode pairs (true by default). Pass `false` to use `.length` of strings that is faster, but gives "incorrect" lengths of strings with unicode pairs - each unicode pair is counted as two characters.
 - _beautify_: format the generated function with [js-beautify](https://github.com/beautify-web/js-beautify) (the validating function is generated without line-breaks). `npm install js-beautify` to use this option. `true` or js-beautify options can be passed.
@@ -141,6 +152,11 @@ npm test
 
 ## Changes history
 
+##### 0.5.0
+
+Schemas are validated against meta-schema before compilation
+
+
 ##### 0.4.1
 
 Custom formats support.

lib/ajv.js

@@ -33,6 +33,7 @@ function Ajv(opts) {
     this.addSchema = addSchema;
     this.getSchema = getSchema;
     this.addFormat = addFormat;
+    this.errorsText = errorsText;
 
     addInitialSchemas();
     addInitialFormats();
@@ -124,9 +125,9 @@ function Ajv(opts) {
         var id = resolve.normalizeId(schema.id);
         if (id) checkUnique(id);
 
-        // var ok = skipValidation || self.opts.validateSchema === false
-        //          || validateSchema(schema);
-        // if (!ok) throw new Error('schema is invalid');
+        var ok = skipValidation || self.opts.validateSchema === false
+                 || validateSchema(schema);
+        if (!ok) console.error('schema is invalid:\n', errorsText());
 
         resolve.ids.call(self, schema);
 
@@ -136,6 +137,20 @@ function Ajv(opts) {
     }
 
 
+    function errorsText(errors, opts) {
+        errors = errors || self.errors;
+        if (!errors) return 'No errors';
+        opts = opts || {};
+        var separator = opts.separator || ', ';
+        var dataVar = opts.dataVar || 'data';
+
+        var text = errors.reduce(function(txt, e) {
+            return e ? txt + e.keyword + ' ' + dataVar + e.dataPath + ': ' + e.message + separator : txt;
+        }, '');
+        return text.slice(0, -separator.length);
+    }
+
+
     function addFormat(name, format) {
         if (typeof format == 'string') format = new RegExp(format);
         self._formats[name] = format;

package.json

@@ -1,6 +1,6 @@
 {
   "name": "ajv",
-  "version": "0.4.15",
+  "version": "0.5.0",
   "description": "Another JSON schema Validator",
   "main": "lib/ajv.js",
   "scripts": {

spec/ajv.spec.js

@@ -39,10 +39,10 @@ describe('Ajv', function () {
       });
     })
 
-    it.skip('should throw if schema is invalid', function() {
-      should.throw(function() {
-        ajv.compile({ type: null });
-      });
+    it('should validate schema when it is compiled', function() {
+      ajv.errors = null;
+      ajv.compile({ type: null });
+      ajv.errors.length .should.be.greaterThan(0);
     });
   });
 

spec/json-schema.spec.js

@@ -31,8 +31,8 @@ var DEBUG = false;
 
 
 var Ajv = require('../lib/ajv')
-  , ajv = Ajv({ beautify: true, _debug: DEBUG })
-  , fullAjv = Ajv({ allErrors: true, verbose: true, format: 'full', beautify: true, _debug: DEBUG });
+  , ajv = Ajv({ beautify: DEBUG, _debug: DEBUG })
+  , fullAjv = Ajv({ allErrors: true, verbose: true, format: 'full', beautify: DEBUG, _debug: DEBUG });
 
 var remoteRefs = {
     'http://localhost:1234/integer.json': require('./JSON-Schema-Test-Suite/remotes/integer.json'),
@@ -64,7 +64,7 @@ function addTests(description, testsPath) {
       (skip ? describe.skip : describe) (file.name, function() {
         var testSets = require(file.path);
         testSets.forEach(function (testSet) {
-          // if (testSet.description != 'restoring root after ref resolution (#12)') return;
+          // if (testSet.description != 'change resolution scope') return;
           (testSet.skip ? describe.skip : describe)(testSet.description, function() {
             var validate, fullValidate;
           // it(testSet.description, function() {