[internal/aws/proxy] adopt component.UseLocalHostAsDefaultHost feature gate (open-telemetry#30987)

Description:
internal/aws/proxy adopts `component.UseLocalHostAsDefaultHost` feature
gate

Link to tracking Issue:

open-telemetry#30702

Fixes
open-telemetry#30986

Documentation:
Updated docs.

---------

Co-authored-by: Pablo Baeyens <[email protected]>
Co-authored-by: Pablo Baeyens <[email protected]>

Author: 2 people

.chloggen/mx-psi_internal-localhostgate.yaml

@@ -20,6 +20,7 @@ subtext: |
     - extension/awsproxy
     - extension/health_check
     - extension/jaegerremotesampling
+    - internal/aws/proxy
     - processor/remotetap
     - receiver/awsfirehose
     - receiver/awsxray

internal/aws/proxy/cfg.go

@@ -6,6 +6,8 @@ package proxy // import "github.com/open-telemetry/opentelemetry-collector-contr
 import (
 	"go.opentelemetry.io/collector/config/confignet"
 	"go.opentelemetry.io/collector/config/configtls"
+
+	"github.com/open-telemetry/opentelemetry-collector-contrib/internal/common/localhostgate"
 )
 
 // Config is the configuration for the local TCP proxy server.
@@ -43,7 +45,7 @@ type Config struct {
 func DefaultConfig() *Config {
 	return &Config{
 		TCPAddr: confignet.TCPAddr{
-			Endpoint: "0.0.0.0:2000",
+			Endpoint: localhostgate.EndpointForPort(2000),
 		},
 		ProxyAddress: "",
 		TLSSetting: configtls.TLSClientSetting{

receiver/awsxrayreceiver/README.md

@@ -63,6 +63,8 @@ The TCP address and port on which this receiver listens for calls from the X-Ray
 
 Default: `0.0.0.0:2000`
 
+The `component.UseLocalHostAsDefaultHost` feature gate changes this to localhost:2000. This will become the default in a future release.
+
 ### proxy_address (Optional)
 Defines the proxy address that the local TCP server forwards HTTP requests to AWS X-Ray backend through. If left unconfigured, requests will be sent directly.