Chapter 4. Examples

This chapter demonstrates the use of AMQ Ruby through example programs.

4.1. Sending messages

This client program connects to a server using <connection-url>, creates a sender for target <address>, sends a message containing <message-body>, closes the connection, and exits.

Example: Sending messages

require 'qpid_proton'

class SendHandler < Qpid::Proton::MessagingHandler
  def initialize(conn_url, address, message_body)
    super()

    @conn_url = conn_url
    @address = address
    @message_body = message_body
  end

  def on_container_start(container)
    conn = container.connect(@conn_url)
    conn.open_sender(@address)
  end

  def on_sender_open(sender)
    puts "SEND: Opened sender for target address '#{sender.target.address}'\n"
  end

  def on_sendable(sender)
    message = Qpid::Proton::Message.new(@message_body)
    sender.send(message)

    puts "SEND: Sent message '#{message.body}'\n"

    sender.close
    sender.connection.close
  end
end

if ARGV.size == 3
  conn_url, address, message_body = ARGV
else
  abort "Usage: send.rb <connection-url> <address> <message-body>\n"
end

handler = SendHandler.new(conn_url, address, message_body)
container = Qpid::Proton::Container.new(handler)
container.run

Running the example

To run the example program, copy it to a local file and invoke it using the ruby command.

$ ruby send.rb amqp://localhost queue1 hello

4.2. Receiving messages

This client program connects to a server using <connection-url>, creates a receiver for source <address>, and receives messages until it is terminated or it reaches <count> messages.

Example: Receiving messages

require 'qpid_proton'

class ReceiveHandler < Qpid::Proton::MessagingHandler
  def initialize(conn_url, address, desired)
    super()

    @conn_url = conn_url
    @address = address

    @desired = desired
    @received = 0
  end

  def on_container_start(container)
    conn = container.connect(@conn_url)
    conn.open_receiver(@address)
  end

  def on_receiver_open(receiver)
    puts "RECEIVE: Opened receiver for source address '#{receiver.source.address}'\n"
  end

  def on_message(delivery, message)
    puts "RECEIVE: Received message '#{message.body}'\n"

    @received += 1

    if @received == @desired
      delivery.receiver.close
      delivery.receiver.connection.close
    end
  end
end

if ARGV.size > 1
  conn_url, address = ARGV[0..1]
else
  abort "Usage: receive.rb <connection-url> <address> [<message-count>]\n"
end

begin
  desired = Integer(ARGV[2])
rescue TypeError
  desired = 0
end

handler = ReceiveHandler.new(conn_url, address, desired)
container = Qpid::Proton::Container.new(handler)
container.run

Running the example

To run the example program, copy it to a local file and invoke it using the ruby command.

$ ruby receive.rb amqp://localhost queue1