Class: SimpleIPC::Socket

Inherits:
Object
  • Object
show all
Defined in:
lib/simple_ipc.rb

Overview

Wrapper class exposing the same API for UNIXSocket and UDPSocket classes.

Instance Method Summary collapse

Constructor Details

#initialize(args = {}) ⇒ Socket

Default initialization hash is:

{
  :port => 5000,       # port, only used for UDPSockets
  :host => LOCALHOST,  # Host to talk with, only used for UDPSockets
  :kind => :unix,      # kind of socket, either :unix or :udp
  :force => true       # if true, force removing of stale socket files
}

Parameters:

  • args (Hash) (defaults to: {}) —

    a hash of config values



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# File 'lib/simple_ipc.rb', line 36

def initialize(args = {})
  @cfg = {
    :port => 5000,
    :host => LOCALHOST,
    :kind => :unix,
    :force => true    
  }
  @cfg.merge! args
  case @cfg[:kind]
  when :unix
    @socket_file = "/tmp/#{$0}.sok"
    @socket = nil
  when :udp
    @socket = UDPSocket.new
  else
    raise ArgumentError, "Either :unix or :udp allowed"
  end
  @open = false
end

Instance Method Details

#close ⇒ Object

Closes the socket and removes the socket file if it exists.



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# File 'lib/simple_ipc.rb', line 111

def close
  @socket.close
  @open = false
  FileUtils::rm(@socket_file) if @socket_file
end

#connect ⇒ Object

Opens the connection. Only has to be called once before sending messages. Only used for client sockets.



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# File 'lib/simple_ipc.rb', line 58

def connect
  return false if @open
  case @cfg[:kind]
  when :unix
    @socket = UNIXSocket.open(@socket_file)
  when :udp
    @socket.connect(@cfg[:host], @cfg[:port])
  end
  @open = true
end

#listen ⇒ Object

Listens for incoming messages, i.e. becomes a server. If @cfg is true, it also silently removes any existing stale socket file, otherwise stops.

Raises:

  • (Errno::EADDRINUSE) —

    when @cfg is false and a socket file already exists



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# File 'lib/simple_ipc.rb', line 80

def listen
  case @cfg[:kind]
  when :unix
    @socket = UNIXServer.open(@socket_file).accept
  when :udp
    @socket.bind(BROADCAST, @cfg[:port])
  end
rescue Errno::EADDRINUSE
  if @cfg[:force] then
    FileUtils::rm(@socket_file)
    retry
  else
    raise Errno::EADDRINUSE, $!
  end
end

#print(string) ⇒ Object

Sends a String through the socket.

Parameters:

  • string (String) —

    the message to be sent



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# File 'lib/simple_ipc.rb', line 71

def print(string)
  @socket.print(string)
end

#recv_nonblock(bytes) ⇒ String

Receives a message of length bytes in non-blocking way.

Parameters:

  • bytes (Integer) —

    the number of characters to be read

Returns:

  • (String) 


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# File 'lib/simple_ipc.rb', line 106

def recv_nonblock(bytes)
  @socket.recv_nonblock(bytes)
end

#recvfrom(bytes) ⇒ String

Receives a message of length bytes.

Parameters:

  • bytes (Integer) —

    the number of characters to be read

Returns:

  • (String) 


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# File 'lib/simple_ipc.rb', line 99

def recvfrom(bytes)
  @socket.recvfrom(bytes)
end