snapshot of https://github.com/grpc/grpc-go.git (master, 2026-09-15; blobs > 131072B omitted)

examples/features/xds/client/main.go

@@ -0,0 +1,73 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Binary main implements a client for Greeter service using gRPC's client-side
+// support for xDS APIs.
+package main
+
+import (
+	"context"
+	"flag"
+	"log"
+	"strings"
+	"time"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials/insecure"
+	xdscreds "google.golang.org/grpc/credentials/xds"
+	pb "google.golang.org/grpc/examples/helloworld/helloworld"
+
+	_ "google.golang.org/grpc/xds" // To install the xds resolvers and balancers.
+)
+
+var (
+	target   = flag.String("target", "xds:///localhost:50051", "uri of the Greeter Server, e.g. 'xds:///helloworld-service:8080'")
+	name     = flag.String("name", "world", "name you wished to be greeted by the server")
+	xdsCreds = flag.Bool("xds_creds", false, "whether the server should use xDS APIs to receive security configuration")
+)
+
+func main() {
+	flag.Parse()
+
+	if !strings.HasPrefix(*target, "xds:///") {
+		log.Fatalf("-target must use a URI with scheme set to 'xds'")
+	}
+
+	creds := insecure.NewCredentials()
+	if *xdsCreds {
+		log.Println("Using xDS credentials...")
+		var err error
+		if creds, err = xdscreds.NewClientCredentials(xdscreds.ClientOptions{FallbackCreds: insecure.NewCredentials()}); err != nil {
+			log.Fatalf("failed to create client-side xDS credentials: %v", err)
+		}
+	}
+	conn, err := grpc.NewClient(*target, grpc.WithTransportCredentials(creds))
+	if err != nil {
+		log.Fatalf("grpc.NewClient(%s) failed: %v", *target, err)
+	}
+	defer conn.Close()
+
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	c := pb.NewGreeterClient(conn)
+	r, err := c.SayHello(ctx, &pb.HelloRequest{Name: *name})
+	if err != nil {
+		log.Fatalf("could not greet: %v", err)
+	}
+	log.Printf("Greeting: %s", r.GetMessage())
+}