| /* |
| * |
| * Copyright 2019 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 client is an example client. |
| package main |
| |
| import ( |
| "context" |
| "flag" |
| "fmt" |
| "log" |
| "time" |
| |
| "google.golang.org/grpc" |
| pb "google.golang.org/grpc/examples/features/proto/echo" |
| "google.golang.org/grpc/keepalive" |
| ) |
| |
| var addr = flag.String("addr", "localhost:50052", "the address to connect to") |
| |
| var kacp = keepalive.ClientParameters{ |
| Time: 10 * time.Second, // send pings every 10 seconds if there is no activity |
| Timeout: time.Second, // wait 1 second for ping ack before considering the connection dead |
| PermitWithoutStream: true, // send pings even without active streams |
| } |
| |
| func main() { |
| flag.Parse() |
| |
| conn, err := grpc.Dial(*addr, grpc.WithInsecure(), grpc.WithKeepaliveParams(kacp)) |
| if err != nil { |
| log.Fatalf("did not connect: %v", err) |
| } |
| defer conn.Close() |
| |
| c := pb.NewEchoClient(conn) |
| |
| ctx, cancel := context.WithTimeout(context.Background(), 3*time.Minute) |
| defer cancel() |
| fmt.Println("Performing unary request") |
| res, err := c.UnaryEcho(ctx, &pb.EchoRequest{Message: "keepalive demo"}) |
| if err != nil { |
| log.Fatalf("unexpected error from UnaryEcho: %v", err) |
| } |
| fmt.Println("RPC response:", res) |
| select {} // Block forever; run with GODEBUG=http2debug=2 to observe ping frames and GOAWAYs due to idleness. |
| } |