go.nanomsg.org/mangos/v3@v3.4.3-0.20240217232803-46464076f1f5/examples/pair/pair.go (about)

     1  // Copyright 2018 The Mangos Authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use file except in compliance with the License.
     5  // You may obtain a copy of the license at
     6  //
     7  //    http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  // pair implements a pair example.  node0 is a listening
    16  // pair socket, and node1 is a dialing pair socket.
    17  //
    18  // To use:
    19  //
    20  //   $ go build .
    21  //   $ url=tcp://127.0.0.1:40899
    22  //   $ ./pair node0 $url & node0=$!
    23  //   $ ./pair node1 $url & node1=$!
    24  //   $ sleep 3
    25  //   $ kill $node0 $node1
    26  //
    27  package main
    28  
    29  import (
    30  	"fmt"
    31  	"os"
    32  	"time"
    33  
    34  	"go.nanomsg.org/mangos/v3"
    35  	"go.nanomsg.org/mangos/v3/protocol/pair"
    36  
    37  	// register transports
    38  	_ "go.nanomsg.org/mangos/v3/transport/all"
    39  )
    40  
    41  func die(format string, v ...interface{}) {
    42  	fmt.Fprintln(os.Stderr, fmt.Sprintf(format, v...))
    43  	os.Exit(1)
    44  }
    45  
    46  func sendName(sock mangos.Socket, name string) {
    47  	fmt.Printf("%s: SENDING \"%s\"\n", name, name)
    48  	if err := sock.Send([]byte(name)); err != nil {
    49  		die("failed sending: %s", err)
    50  	}
    51  }
    52  
    53  func recvName(sock mangos.Socket, name string) {
    54  	var msg []byte
    55  	var err error
    56  	if msg, err = sock.Recv(); err == nil {
    57  		fmt.Printf("%s: RECEIVED: \"%s\"\n", name, string(msg))
    58  	}
    59  }
    60  
    61  func sendRecv(sock mangos.Socket, name string) {
    62  	for {
    63  		sock.SetOption(mangos.OptionRecvDeadline, 100*time.Millisecond)
    64  		recvName(sock, name)
    65  		time.Sleep(time.Second)
    66  		sendName(sock, name)
    67  	}
    68  }
    69  
    70  func node0(url string) {
    71  	var sock mangos.Socket
    72  	var err error
    73  	if sock, err = pair.NewSocket(); err != nil {
    74  		die("can't get new pair socket: %s", err)
    75  	}
    76  	if err = sock.Listen(url); err != nil {
    77  		die("can't listen on pair socket: %s", err.Error())
    78  	}
    79  	sendRecv(sock, "node0")
    80  }
    81  
    82  func node1(url string) {
    83  	var sock mangos.Socket
    84  	var err error
    85  
    86  	if sock, err = pair.NewSocket(); err != nil {
    87  		die("can't get new pair socket: %s", err.Error())
    88  	}
    89  	if err = sock.Dial(url); err != nil {
    90  		die("can't dial on pair socket: %s", err.Error())
    91  	}
    92  	sendRecv(sock, "node1")
    93  }
    94  
    95  func main() {
    96  	if len(os.Args) > 2 && os.Args[1] == "node0" {
    97  		node0(os.Args[2])
    98  		os.Exit(0)
    99  	}
   100  	if len(os.Args) > 2 && os.Args[1] == "node1" {
   101  		node1(os.Args[2])
   102  		os.Exit(0)
   103  	}
   104  	fmt.Fprintf(os.Stderr, "Usage: pair node0|node1 <URL>\n")
   105  	os.Exit(1)
   106  }