extension: address review feedback

Author: jijo-OO7

extension/example_test.go

@@ -0,0 +1,65 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package extension_test
+
+import (
+	"context"
+	"fmt"
+
+	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/extension"
+)
+
+// exampleExtension is a minimal extension that reports its lifecycle.
+type exampleExtension struct {
+	id component.ID
+}
+
+// Start is called by the Collector when the extension is started.
+func (e *exampleExtension) Start(_ context.Context, _ component.Host) error {
+	fmt.Printf("extension %q started\n", e.id)
+	return nil
+}
+
+// Shutdown is called by the Collector when the extension is stopped.
+func (e *exampleExtension) Shutdown(_ context.Context) error {
+	fmt.Printf("extension %q stopped\n", e.id)
+	return nil
+}
+
+func createExampleConfig() component.Config {
+	return struct{}{}
+}
+
+func createExampleExtension(_ context.Context, set extension.Settings, _ component.Config) (extension.Extension, error) {
+	return &exampleExtension{id: set.ID}, nil
+}
+
+// Example demonstrates how a Factory creates an extension using Settings.ID.
+func Example() {
+	extType := component.MustNewType("example")
+
+	factory := extension.NewFactory(
+		extType,
+		createExampleConfig,
+		createExampleExtension,
+		component.StabilityLevelDevelopment,
+	)
+
+	settings := extension.Settings{
+		ID: component.NewID(extType),
+	}
+
+	ext, err := factory.Create(context.Background(), settings, factory.CreateDefaultConfig())
+	if err != nil {
+		panic(err)
+	}
+
+	_ = ext.Start(context.Background(), nil)
+	_ = ext.Shutdown(context.Background())
+
+	// Output:
+	// extension "example" started
+	// extension "example" stopped
+}