update README.md

README.md

@@ -1,2 +1,106 @@
 # jaeger-middleware
 An extensively configurable Go web middleware that integrates Jaeger for distributed tracing.
+
+## Usage
+
+### Installation
+
+```bash
+go get github.com/makonike/jaeger-middleware
+```
+
+### Example
+
+#### Server
+
+```go
+func main() {
+	tp, _ := middleware.TracerProvider("http://localhost:14268/api/traces", false)
+	otel.SetTracerProvider(tp)
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	// Cleanly shutdown and flush telemetry when the application exits.
+	defer func(ctx context.Context) {
+		// Do not make the application hang when it is shutdown.
+		ctx, cancel = context.WithTimeout(ctx, time.Second*5)
+		defer cancel()
+		if err := tp.Shutdown(ctx); err != nil {
+			fmt.Println("failed to shutdown TracerProvider: ", err)
+		}
+	}(ctx)
+
+	server := grpc.NewServer(
+		grpc.UnaryInterceptor(middleware.NewJaegerServerMiddleware().UnaryInterceptor),
+		grpc.StreamInterceptor(middleware.NewJaegerServerMiddleware().StreamInterceptor),
+	)
+	proto.RegisterTestServiceServer(server, new(test.UserService))
+	list, err := net.Listen("tcp", ":50055")
+	if err != nil {
+		log.Fatal(err)
+	}
+	err = server.Serve(list)
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+```
+
+#### Client
+```go
+func main() {
+	tp, _ := middleware.TracerProvider("http://localhost:14268/api/traces", false)
+	otel.SetTracerProvider(tp)
+	var addr string
+	addr = ":50055"
+	ctx := context.WithValue(context.Background(), "trace-id", "cdde169b504ec847521a2cf1d1ffa9f9")
+	req := &proto.GetReq{
+		Name: "xxx",
+	}
+	conn, err := grpc.Dial(addr,
+		grpc.WithTransportCredentials(insecure.NewCredentials()),
+		grpc.WithUnaryInterceptor(middleware.NewJaegerClientMiddleware().UnaryClientInterceptor),
+		grpc.WithStreamInterceptor(middleware.NewJaegerClientMiddleware().StreamClientInterceptor),
+	)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer conn.Close()
+	client := proto.NewTestServiceClient(conn)
+	resp, err := client.Get(ctx, req)
+	assert.Nil(t, err)
+}
+```
+
+## Configuration
+
+At present, configuration exclusively relies on manipulation of environmental variables within the operating system. Hence, it is advisable to operate a distinct application within an individual container. This approach facilitates the accommodation of multiple applications on a single host, each employing distinct customized configurations.
+
+- CLUSTER_NAME, default default_cluster
+- NAMESPACE, default default_namespace
+- DEPLOYMENT, default default_deployment
+- SERVICE_NAME, default default_hostname
+- ENVIRONMENT, default default_pod
+- TRACE_HEADER, default trace-id
+
+The identifying key for the trace_id propagated across the chain of communication.
+
+- MAX_BOX_SIZE, default 10240
+
+If the size of the input body or the returned error message exceeds the MAX_BOX_SIZE, it will not be logged.
+
+- SERVER_ENABLED, default true 
+
+If configured as 'false,' the server middleware will remain inactive.
+
+- CLIENT_ENABLED=dev, default true
+
+If configured as 'false,' the client middleware will remain inactive.
+
+## Effect
+
+![img.png](/img/img.png)
+
+## Reference
+
+TODO

middleware/options.go

@@ -76,6 +76,9 @@ func DefaultOptions() Options {
 		if os.Getenv("ENVIRONMENT") != "" {
 			o.meta.Environment = os.Getenv("ENVIRONMENT")
 		}
+		if os.Getenv("TRACE_HEADER") != "" {
+			o.meta.Environment = os.Getenv("TRACE_HEADER")
+		}
 
 		o.maxBodySize = 10240
 		o.serverEnabled = true

middleware_test.go

@@ -54,7 +54,7 @@ func TestMiddlewareClient(t *testing.T) {
 	var addr string
 	addr = ":50055"
 	ctx := context.WithValue(context.Background(), "trace-id", "cdde169b504ec847521a2cf1d1ffa9f9")
-	req1 := &proto.GetReq{
+	req := &proto.GetReq{
 		Name: "www3",
 	}
 	conn, err := grpc.Dial(addr,
@@ -67,7 +67,7 @@ func TestMiddlewareClient(t *testing.T) {
 	}
 	defer conn.Close()
 	client := proto.NewTestServiceClient(conn)
-	resp, err := client.Get(ctx, req1)
+	resp, err := client.Get(ctx, req)
 	assert.Nil(t, err)
 	assert.Equal(t, "www", resp.GetName())
 }