[extension/httpforwarder] use default http client settings (open-tele…

…metry#29887)

**Description:**
Use confighttp.HTTPDefaultClientSettings when configuring the
HTTPClientSettings for the httpforwarder extension.

**Link to tracking Issue:**
open-telemetry#6641

.chloggen/httpforwarder_use_default_http_client_settings.yaml

@@ -0,0 +1,30 @@
+# 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: httpforwarder
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Use confighttp.HTTPDefaultClientSettings when configuring the HTTPClientSettings for the httpforwarder extension.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [6641]
+
+# (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: |
+  By default, the HTTP forwarder extension will now use the defaults set in the extension:
+  * The idle connection timeout is set to 90s.
+  * The max idle connection count is set to 100.
+
+# 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/httpforwarder/config_test.go

@@ -20,6 +20,8 @@ import (
 
 func TestLoadConfig(t *testing.T) {
 	t.Parallel()
+	maxIdleConns := 42
+	idleConnTimeout := 80 * time.Second
 
 	tests := []struct {
 		id       component.ID
@@ -40,7 +42,9 @@ func TestLoadConfig(t *testing.T) {
 					Headers: map[string]configopaque.String{
 						"otel_http_forwarder": "dev",
 					},
-					Timeout: 5 * time.Second,
+					MaxIdleConns:    &maxIdleConns,
+					IdleConnTimeout: &idleConnTimeout,
+					Timeout:         5 * time.Second,
 				},
 			},
 		},

extension/httpforwarder/factory.go

@@ -29,13 +29,13 @@ func NewFactory() extension.Factory {
 }
 
 func createDefaultConfig() component.Config {
+	httpClientSettings := confighttp.NewDefaultHTTPClientSettings()
+	httpClientSettings.Timeout = 10 * time.Second
 	return &Config{
 		Ingress: confighttp.HTTPServerSettings{
 			Endpoint: defaultEndpoint,
 		},
-		Egress: confighttp.HTTPClientSettings{
-			Timeout: 10 * time.Second,
-		},
+		Egress: httpClientSettings,
 	}
 }
 

extension/httpforwarder/testdata/config.yaml

@@ -6,4 +6,6 @@ http_forwarder/1:
     endpoint: http://target/
     headers:
       otel_http_forwarder: dev
+    idle_conn_timeout: 80s
+    max_idle_conns: 42
     timeout: 5s