[all] Promote component.UseLocalHostAsDefaultHost feature gate to beta (#33658)

**Description:** <Describe what has changed.>
<!--Ex. Fixing a bug - Describe the bug and how this fixes the issue.
Ex. Adding a feature - Explain what this achieves.-->

Counterpart to open-telemetry/opentelemetry-collector/pull/10352.

**Link to tracking Issue:**
open-telemetry/opentelemetry-collector/issues/8510

Author: mx-psi

.chloggen/mx-psi_localhost-fg.yaml

@@ -0,0 +1,45 @@
+# Use this changelog template to create an entry for release notes.
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: breaking
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: all
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "Promote `component.UseLocalHostAsDefaultHost` feature gate to beta. This changes default endpoints from 0.0.0.0 to localhost"
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [30702]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext: |
+  This change affects the following components:
+    - extension/awsproxy
+    - extension/health_check
+    - extension/health_checkv2
+    - extension/jaegerremotesampling
+    - internal/aws/proxy
+    - processor/remotetap
+    - receiver/awsfirehose
+    - receiver/awsxray
+    - receiver/influxdb
+    - receiver/jaeger
+    - receiver/loki
+    - receiver/opencensus
+    - receiver/sapm
+    - receiver/signalfx
+    - receiver/skywalking
+    - receiver/splunk_hec
+    - receiver/zipkin
+    - receiver/zookeeper
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

extension/awsproxy/README.md

@@ -39,9 +39,9 @@ extensions:
 ### endpoint (Optional)
 The TCP address and port on which this proxy listens for requests.
 
-Default: `0.0.0.0:2000`
+Default: `localhost:2000`
 
-The `component.UseLocalHostAsDefaultHost` feature gate changes this to localhost:2000. This will become the default in a future release.
+You can temporarily disable the `component.UseLocalHostAsDefaultHost` feature gate to change this to `0.0.0.0:2000`. This feature gate will be removed in a future release.
 
 
 ### proxy_address (Optional)

extension/awsproxy/factory_test.go

@@ -28,7 +28,7 @@ func TestFactory_CreateDefaultConfig(t *testing.T) {
 	assert.Equal(t, &Config{
 		ProxyConfig: proxy.Config{
 			TCPAddrConfig: confignet.TCPAddrConfig{
-				Endpoint: "0.0.0.0:2000",
+				Endpoint: "localhost:2000",
 			},
 		},
 	}, cfg)

extension/healthcheckextension/README.md

@@ -28,7 +28,7 @@ liveness and/or readiness probe on Kubernetes.
 
 The following settings are required:
 
-- `endpoint` (default = 0.0.0.0:13133): Address to publish the health check status. For full list of `ServerConfig` refer [here](https://github.com/open-telemetry/opentelemetry-collector/tree/main/config/confighttp). The `component.UseLocalHostAsDefaultHost` feature gate changes this to localhost:13133. This will become the default in a future release.
+- `endpoint` (default = localhost:13133): Address to publish the health check status. For full list of `ServerConfig` refer [here](https://github.com/open-telemetry/opentelemetry-collector/tree/main/config/confighttp). You can temporarily disable the `component.UseLocalHostAsDefaultHost` feature gate to change this to 0.0.0.0:13133. This feature gate will be removed in a future release.
 - `path` (default = "/"): Specifies the path to be configured for the health check server.
 - `response_body` (default = ""): Specifies a static body that overrides the default response returned by the health check service. 
 

extension/healthcheckextension/factory_test.go

@@ -20,7 +20,7 @@ func TestFactory_CreateDefaultConfig(t *testing.T) {
 	cfg := createDefaultConfig()
 	assert.Equal(t, &Config{
 		ServerConfig: confighttp.ServerConfig{
-			Endpoint: "0.0.0.0:13133",
+			Endpoint: "localhost:13133",
 		},
 		CheckCollectorPipeline: defaultCheckCollectorPipelineSettings(),
 		Path:                   "/",

extension/healthcheckv2extension/README.md

@@ -38,7 +38,7 @@ liveness and/or readiness probe on Kubernetes.
 
 The following settings are required:
 
-- `endpoint` (default = 0.0.0.0:13133): Address to publish the health check status. For full list of `ServerConfig` refer [here](https://github.com/open-telemetry/opentelemetry-collector/tree/main/config/confighttp). The `component.UseLocalHostAsDefaultHost` feature gate changes this to localhost:13133. This will become the default in a future release.
+- `endpoint` (default = localhost:13133): Address to publish the health check status. For full list of `ServerConfig` refer [here](https://github.com/open-telemetry/opentelemetry-collector/tree/main/config/confighttp). You can temporarily disable the `component.UseLocalHostAsDefaultHost` feature gate to change this to 0.0.0.0:13133. This feature gate will be removed in a future release.
 - `path` (default = "/"): Specifies the path to be configured for the health check server.
 - `response_body` (default = ""): Specifies a static body that overrides the default response returned by the health check service.
 - `check_collector_pipeline:` (deprecated and ignored): Settings of collector pipeline health check
@@ -425,4 +425,4 @@ begin streaming.
 There are plans to provide the ability to export status events as OTLP logs adhering to the event
 semantic conventions.
 
-[grpc_health_v1 service]: https://github.com/grpc/grpc-proto/blob/master/grpc/health/v1/health.proto
+[grpc_health_v1 service]: https://github.com/grpc/grpc-proto/blob/master/grpc/health/v1/health.proto

extension/jaegerremotesampling/README.md

@@ -14,10 +14,10 @@
 This extension allows serving sampling strategies following the Jaeger's remote sampling API. This extension can be configured to proxy requests to a backing remote sampling server, which could potentially be a Jaeger Collector down the pipeline, or a static JSON file from the local file system.
 
 By default, two listeners are made available:
-- `0.0.0.0:5778`, following the legacy remote sampling endpoint as defined by Jaeger
-- `0.0.0.0:14250`, following the gRPC remote sampling endpoint, also defined by Jaeger
+- `localhost:5778`, following the legacy remote sampling endpoint as defined by Jaeger
+- `localhost:14250`, following the gRPC remote sampling endpoint, also defined by Jaeger
 
-The `component.UseLocalHostAsDefaultHost` feature gate changes this to localhost:9943. This will become the default in a future release.
+You can temporarily disable the `component.UseLocalHostAsDefaultHost` feature gate to change this to `0.0.0.0:5778` and `0.0.0.0:14250` respectively. This feature gate will be removed in a future release.
 
 
 Note that the port `14250` will clash with the Jaeger Receiver. When both are used, it's recommended to change this extension to use another port.

extension/jaegerremotesampling/config_test.go

@@ -29,9 +29,9 @@ func TestLoadConfig(t *testing.T) {
 		{
 			id: component.NewID(metadata.Type),
 			expected: &Config{
-				HTTPServerConfig: &confighttp.ServerConfig{Endpoint: "0.0.0.0:5778"},
+				HTTPServerConfig: &confighttp.ServerConfig{Endpoint: "localhost:5778"},
 				GRPCServerConfig: &configgrpc.ServerConfig{NetAddr: confignet.AddrConfig{
-					Endpoint:  "0.0.0.0:14250",
+					Endpoint:  "localhost:14250",
 					Transport: confignet.TransportTypeTCP,
 				}},
 				Source: Source{
@@ -44,9 +44,9 @@ func TestLoadConfig(t *testing.T) {
 		{
 			id: component.NewIDWithName(metadata.Type, "1"),
 			expected: &Config{
-				HTTPServerConfig: &confighttp.ServerConfig{Endpoint: "0.0.0.0:5778"},
+				HTTPServerConfig: &confighttp.ServerConfig{Endpoint: "localhost:5778"},
 				GRPCServerConfig: &configgrpc.ServerConfig{NetAddr: confignet.AddrConfig{
-					Endpoint:  "0.0.0.0:14250",
+					Endpoint:  "localhost:14250",
 					Transport: confignet.TransportTypeTCP,
 				}},
 				Source: Source{

extension/jaegerremotesampling/factory_test.go

@@ -18,9 +18,9 @@ import (
 func TestCreateDefaultConfig(t *testing.T) {
 	// prepare and test
 	expected := &Config{
-		HTTPServerConfig: &confighttp.ServerConfig{Endpoint: "0.0.0.0:5778"},
+		HTTPServerConfig: &confighttp.ServerConfig{Endpoint: "localhost:5778"},
 		GRPCServerConfig: &configgrpc.ServerConfig{NetAddr: confignet.AddrConfig{
-			Endpoint:  "0.0.0.0:14250",
+			Endpoint:  "localhost:14250",
 			Transport: confignet.TransportTypeTCP,
 		}},
 	}

internal/common/localhostgate/featuregate.go

@@ -23,7 +23,7 @@ const UseLocalHostAsDefaultHostID = "component.UseLocalHostAsDefaultHost"
 var UseLocalHostAsDefaultHostfeatureGate = mustRegisterOrLoad(
 	featuregate.GlobalRegistry(),
 	UseLocalHostAsDefaultHostID,
-	featuregate.StageAlpha,
+	featuregate.StageBeta,
 	featuregate.WithRegisterDescription("controls whether server-like receivers and extensions such as the OTLP receiver use localhost as the default host for their endpoints"),
 )
 
@@ -60,8 +60,8 @@ func EndpointForPort(port int) string {
 // LogAboutUseLocalHostAsDefault logs about the upcoming change from 0.0.0.0 to localhost on server-like components.
 func LogAboutUseLocalHostAsDefault(logger *zap.Logger) {
 	if !UseLocalHostAsDefaultHostfeatureGate.IsEnabled() {
-		logger.Warn(
-			"The default endpoints for all servers in components will change to use localhost instead of 0.0.0.0 in a future version. Use the feature gate to preview the new default.",
+		logger.Info(
+			"The default endpoints for all servers in components have changed to use localhost instead of 0.0.0.0. Use the feature gate to temporarily revert to the previous default.",
 			zap.String("feature gate ID", UseLocalHostAsDefaultHostID),
 		)
 	}