github.com/jingruilea/kubeedge@v1.2.0-beta.0.0.20200410162146-4bb8902b3879/cloud/pkg/csidriver/uds.go (about)

     1  /*
     2  Copyright 2019 The KubeEdge Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package csidriver
    18  
    19  import (
    20  	"net"
    21  
    22  	"k8s.io/klog"
    23  )
    24  
    25  const (
    26  	// DefaultBufferSize represents default buffer size
    27  	DefaultBufferSize = 10480
    28  )
    29  
    30  // UnixDomainSocket struct
    31  type UnixDomainSocket struct {
    32  	filename   string
    33  	buffersize int
    34  }
    35  
    36  // NewUnixDomainSocket create new socket
    37  func NewUnixDomainSocket(filename string, buffersize ...int) *UnixDomainSocket {
    38  	size := DefaultBufferSize
    39  	if buffersize != nil {
    40  		size = buffersize[0]
    41  	}
    42  	us := UnixDomainSocket{filename: filename, buffersize: size}
    43  	return &us
    44  }
    45  
    46  // Connect for client
    47  func (us *UnixDomainSocket) Connect() (net.Conn, error) {
    48  	// parse
    49  	proto, addr, err := parseEndpoint(us.filename)
    50  	if err != nil {
    51  		klog.Errorf("failed to parseEndpoint: %v", err)
    52  		return nil, err
    53  	}
    54  
    55  	// dial
    56  	c, err := net.Dial(proto, addr)
    57  	if err != nil {
    58  		klog.Errorf("failed to dial: %v", err)
    59  		return nil, err
    60  	}
    61  	return c, nil
    62  }
    63  
    64  // Send msg for client
    65  func (us *UnixDomainSocket) Send(c net.Conn, context string) (string, error) {
    66  	// send msg
    67  	_, err := c.Write([]byte(context))
    68  	if err != nil {
    69  		klog.Errorf("failed to write buffer: %v", err)
    70  		return "", err
    71  	}
    72  
    73  	// read response
    74  	buf := make([]byte, us.buffersize)
    75  	nr, err := c.Read(buf)
    76  	if err != nil {
    77  		klog.Errorf("failed to read buffer: %v", err)
    78  		return "", err
    79  	}
    80  	return string(buf[0:nr]), nil
    81  }