chore: add example for component interceptor

example_test.go

@@ -53,7 +53,7 @@ func Example_componentRefAndCall() {
 // This example demonstrates how to use [kod.LazyInit] to defer component initialization until it is needed.
 func Example_componentLazyInit() {
 	kod.Run(context.Background(), func(ctx context.Context, app *helloworld.App) error {
-		app.HelloLazy.Get().SayHello(ctx)
+		app.HelloWorldLazy.Get().SayHello(ctx)
 		app.HelloWorld.Get().SayHello(ctx)
 		return nil
 	})
@@ -169,8 +169,8 @@ func Example_openTelemetryMetric() {
 	// helloWorld shutdown
 }
 
-// This example demonstrates how to use [kod.WithInterceptors] to provide a custom interceptor to the application.
-func Example_interceptor() {
+// This example demonstrates how to use [kod.WithInterceptors] to provide global interceptors to the application.
+func Example_interceptorGlobal() {
 	interceptor := interceptor.Interceptor(func(ctx context.Context, info interceptor.CallInfo, req, res []interface{}, next interceptor.HandleFunc) error {
 		fmt.Println("Before call")
 		err := next(ctx, info, req, res)
@@ -190,7 +190,21 @@ func Example_interceptor() {
 	// helloWorld shutdown
 }
 
-// This example demonstrates how to use built-in interceptors
+// This example demonstrates how to use [kod.WithInterceptors] to provide component-specific interceptors to the application.
+func Example_interceptorComponent() {
+	kod.Run(context.Background(), func(ctx context.Context, app *helloworld.App) error {
+		app.HelloWorldInterceptor.Get().SayHello(ctx)
+		return nil
+	})
+	// Output:
+	// helloWorld init
+	// Before call
+	// Hello, Interceptor!
+	// After call
+	// helloWorld shutdown
+}
+
+// This example demonstrates how to use built-in interceptors with [kod.WithInterceptors].
 // Such as [krecovery.Interceptor], [ktrace.Interceptor], and [kmetric.Interceptor] ...
 func Example_interceptorBuiltin() {
 	kod.Run(context.Background(), func(ctx context.Context, app *helloworld.App) error {

examples/helloworld/helloworld.go

@@ -5,14 +5,16 @@ import (
 	"fmt"
 
 	"github.com/go-kod/kod"
+	"github.com/go-kod/kod/interceptor"
 )
 
 type App struct {
 	kod.Implements[kod.Main]
 	kod.WithGlobalConfig[GlobalConfig]
 
-	HelloWorld kod.Ref[HelloWorld]
-	HelloLazy  kod.Ref[HelloLazy]
+	HelloWorld            kod.Ref[HelloWorld]
+	HelloWorldLazy        kod.Ref[HelloWorldLazy]
+	HelloWorldInterceptor kod.Ref[HelloWorldInterceptor]
 }
 
 type GlobalConfig struct {
@@ -44,21 +46,40 @@ func (h *helloWorld) Shutdown(ctx context.Context) error {
 	return nil
 }
 
-type lazyHelloBob struct {
-	kod.Implements[HelloLazy]
+type lazyHelloWorld struct {
+	kod.Implements[HelloWorldLazy]
 	kod.LazyInit
 }
 
-func (h *lazyHelloBob) Init(ctx context.Context) error {
+func (h *lazyHelloWorld) Init(ctx context.Context) error {
 	fmt.Println("lazyHelloBob init")
 	return nil
 }
 
-func (h *lazyHelloBob) SayHello(ctx context.Context) {
+func (h *lazyHelloWorld) SayHello(ctx context.Context) {
 	fmt.Println("Hello, Bob!")
 }
 
-func (h *lazyHelloBob) Shutdown(ctx context.Context) error {
+func (h *lazyHelloWorld) Shutdown(ctx context.Context) error {
 	fmt.Println("lazyHelloBob shutdown")
 	return nil
 }
+
+type helloWorldInterceptor struct {
+	kod.Implements[HelloWorldInterceptor]
+}
+
+func (h *helloWorldInterceptor) SayHello(ctx context.Context) {
+	fmt.Println("Hello, Interceptor!")
+}
+
+func (h *helloWorldInterceptor) Interceptors() []interceptor.Interceptor {
+	return []interceptor.Interceptor{
+		func(ctx context.Context, info interceptor.CallInfo, req, reply []any, invoker interceptor.HandleFunc) error {
+			fmt.Println("Before call")
+			err := invoker(ctx, info, req, reply)
+			fmt.Println("After call")
+			return err
+		},
+	}
+}