nanomsg.org/go/mangos/v2@v2.0.9-0.20200203084354-8a092611e461/examples/raw/client.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  package main
    16  
    17  import (
    18  	"encoding/binary"
    19  	"fmt"
    20  	"sync"
    21  
    22  	"nanomsg.org/go/mangos/v2"
    23  	"nanomsg.org/go/mangos/v2/protocol/req"
    24  
    25  	// register transports
    26  	_ "nanomsg.org/go/mangos/v2/transport/all"
    27  )
    28  
    29  // synchronize our output messaging so we don't overlap
    30  var lock sync.Mutex
    31  
    32  func clientWorker(url string, id int) {
    33  	var sock mangos.Socket
    34  	var m *mangos.Message
    35  	var err error
    36  
    37  	if sock, err = req.NewSocket(); err != nil {
    38  		die("can't get new req socket: %s", err.Error())
    39  	}
    40  
    41  	// Leave this in Cooked mode!
    42  
    43  	if err = sock.Dial(url); err != nil {
    44  		die("can't dial on req socket: %s", err.Error())
    45  	}
    46  
    47  	// send an empty messsage
    48  	m = mangos.NewMessage(1)
    49  	if err = sock.SendMsg(m); err != nil {
    50  		die("can't send request: %s", err.Error())
    51  	}
    52  
    53  	if m, err = sock.RecvMsg(); err != nil {
    54  		die("can't recv reply: %s", err.Error())
    55  	}
    56  	sock.Close()
    57  
    58  	if len(m.Body) != 4 {
    59  		die("bad response len: %d", len(m.Body))
    60  	}
    61  
    62  	worker := binary.BigEndian.Uint32(m.Body[0:])
    63  
    64  	lock.Lock()
    65  	fmt.Printf("Client: %4d   Server: %4d\n", id, worker)
    66  	lock.Unlock()
    67  }
    68  
    69  func client(url string, nworkers int) {
    70  
    71  	var wg sync.WaitGroup
    72  	for i := 0; i < nworkers; i++ {
    73  		wg.Add(1)
    74  		go func(i int) {
    75  			defer wg.Done()
    76  			clientWorker(url, i)
    77  		}(i)
    78  	}
    79  	wg.Wait()
    80  
    81  }