Class: Bunny::Client

Inherits:
Qrack::Client show all
Defined in:
lib/ext/bunny-0.6.0/lib/bunny/client08.rb

Overview

DESCRIPTION:

The Client class provides the major Bunny API methods.

Constant Summary

Constants inherited from Qrack::Client

Qrack::Client::CONNECT_TIMEOUT, Qrack::Client::RETRY_DELAY

Instance Attribute Summary collapse

Attributes inherited from Qrack::Client

#channel, #channels, #connecting, #exchanges, #heartbeat, #host, #logfile, #logging, #message_in, #message_out, #port, #queues, #spec, #status, #vhost

Instance Method Summary collapse

Methods inherited from Qrack::Client

#close, #connected?, #connecting?, #next_payload, #read, #returned_message, #switch_channel, #write

Constructor Details

#initialize(opts = {}) ⇒ Client

DESCRIPTION:

Sets up a Bunny::Client object ready for connection to a broker/server. Client.status is set to :not_connected.

OPTIONS:

  • :host => 'hostname' (default = 'localhost')

  • :port => portno (default = 5672 or 5671 if :ssl set to true)

  • :vhost => 'vhostname' (default = '/')

  • :user => 'username' (default = 'guest')

  • :pass => 'password' (default = 'guest')

  • :ssl => true or false (default = false) - If set to true, ssl encryption will be used and port will default to 5671.

  • :verify_ssl => true or false (default = true) - If ssl is enabled, this will cause OpenSSL to validate the server certificate unless this parameter is set to false.

  • :logfile => 'logfilepath' (default = nil)

  • :logging => true or false (default) - If set to true, session information is sent to STDOUT if :logfile has not been specified. Otherwise, session information is written to :logfile.

  • :insist => true or false (default) - In a configuration with multiple load-sharing servers, the server may respond to a Connection::Open method with a Connection::Redirect. The insist option, if set to true, tells the server that the client is insisting on a connection to the specified server.

  • :frame_max => maximum frame size in bytes (default = 131072)

  • :channel_max => maximum number of channels (default = 0 no maximum)

  • :heartbeat => number of seconds (default = 0 no heartbeat)

  • :connect_timeout => number of seconds before Qrack::ConnectionTimeout is raised (default = 5)



49
50
51
52
53
54
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 49

def initialize(opts = {})
			super
			@spec = '0-8'
			@port = opts[:port] || (opts[:ssl] ? Qrack::Protocol::SSL_PORT : Qrack::Protocol::PORT)
  @insist = opts[:insist]
end

Instance Attribute Details

#ticket ⇒ Object

Returns the value of attribute ticket.



13
14
15
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 13

def ticket
  @ticket
end

Instance Method Details

#check_response(received_method, expected_method, err_msg, err_class = Bunny::ProtocolError) ⇒ Object

DESCRIPTION:

Checks response from AMQP methods and takes appropriate action



64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 64

def check_response(received_method, expected_method, err_msg, err_class = Bunny::ProtocolError)
	case
		when received_method.is_a?(Qrack::Protocol::Connection::Close)
			# Clean up the socket
			close_socket
			
			raise Bunny::ForcedConnectionCloseError,
				"Error Reply Code: #{received_method.reply_code}\nError Reply Text: #{received_method.reply_text}"
				
		when received_method.is_a?(Qrack::Protocol::Channel::Close)
			# Clean up the channel
			channel.active = false

			raise Bunny::ForcedChannelCloseError,
				"Error Reply Code: #{received_method.reply_code}\nError Reply Text: #{received_method.reply_text}"
				
		when !received_method.is_a?(expected_method)
			raise err_class, err_msg
			
		else
			:response_ok
	end
end

#close_connection ⇒ Object 



88
89
90
91
92
93
94
95
96
97
98
99
100
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 88

def close_connection
			# Set client channel to zero
  switch_channel(0)
		
			send_frame(
   Qrack::Protocol::Connection::Close.new(:reply_code => 200, :reply_text => 'Goodbye', :class_id => 0, :method_id => 0)
 )
	
			method = next_method
			
			check_response(method, Qrack::Protocol::Connection::CloseOk, "Error closing connection")
 
end

#create_channel ⇒ Object 



102
103
104
105
106
107
108
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 102

def create_channel
	channels.each do |c|
		return c if (!c.open? and c.number != 0)
	end
	# If no channel to re-use instantiate new one
	Bunny::Channel.new(self)
end

#exchange(name, opts = {}) ⇒ Object

DESCRIPTION:

Declares an exchange to the broker/server. If the exchange does not exist, a new one is created using the arguments passed in. If the exchange already exists, the existing object is returned. If an error occurs a Bunny::ProtocolError is raised.

OPTIONS:

  • :type => one of :direct (default), :fanout, :topic, :headers

  • :passive => true or false - If set to true, the server will not create the exchange. The client can use this to check whether an exchange exists without modifying the server state.

  • :durable => true or false (default) - If set to true when creating a new exchange, the exchange will be marked as durable. Durable exchanges remain active when a server restarts. Non-durable exchanges (transient exchanges) are purged if/when a server restarts.

  • :auto_delete => true or false (default) - If set to true, the exchange is deleted when all queues have finished using it.

  • :nowait => true or false (default) - Ignored by Bunny, always false.

RETURNS:

Exchange



136
137
138
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 136

def exchange(name, opts = {})
    exchanges[name] || Bunny::Exchange.new(self, name, opts)
end

#init_connection ⇒ Object 



140
141
142
143
144
145
146
147
148
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 140

def init_connection
	write(Qrack::Protocol::HEADER)
    write([1, 1, Qrack::Protocol::VERSION_MAJOR, Qrack::Protocol::VERSION_MINOR].pack('C4'))

	frame = next_frame
	if frame.nil? or !frame.payload.is_a?(Qrack::Protocol::Connection::Start)
		raise Bunny::ProtocolError, 'Connection initiation failed'
	end
end

#next_frame(opts = {}) ⇒ Object

Raises:



150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 150

def next_frame(opts = {})
  frame = nil
			
			case
when channel.frame_buffer.size > 0
	frame = channel.frame_buffer.shift
when opts.has_key?(:timeout)
     Timeout::timeout(opts[:timeout], Qrack::ClientTimeout) do
       frame = Qrack::Transport::Frame.parse(buffer)
     end
   else
     frame = Qrack::Transport::Frame.parse(buffer)
  end
			
			@logger.info("received") { frame } if @logging
		
			raise Bunny::ConnectionError, 'No connection to server' if (frame.nil? and !connecting?)
			
			# Monitor server activity and discard heartbeats
			@message_in = true
			
			case
when frame.is_a?(Qrack::Transport::Heartbeat)
	next_frame(opts)
when frame.nil?
	frame
when ((frame.channel != channel.number) and (frame.channel != 0))
	channel.frame_buffer << frame
	next_frame(opts)
else
	frame
			end
			
end

#open_connection ⇒ Object

Raises:



185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 185

def open_connection
	send_frame(
      Qrack::Protocol::Connection::StartOk.new(
        {:platform => 'Ruby', :product => 'Bunny', :information => 'http://github.com/celldee/bunny', :version => VERSION},
        'AMQPLAIN',
        {:LOGIN => @user, :PASSWORD => @pass},
        'en_US'
      )
    )

    frame = next_frame
	raise Bunny::ProtocolError, "Connection failed - user: #{@user}" if frame.nil?
	
	method = frame.payload

    if method.is_a?(Qrack::Protocol::Connection::Tune)
      send_frame(
        Qrack::Protocol::Connection::TuneOk.new( :channel_max => @channel_max, :frame_max => @frame_max, :heartbeat => @heartbeat)
      )
    end

    send_frame(
      Qrack::Protocol::Connection::Open.new(:virtual_host => @vhost, :capabilities => '', :insist => @insist)
    )

    case method = next_method
    when Qrack::Protocol::Connection::OpenOk
      :ok
    when Qrack::Protocol::Connection::Redirect
		raise Bunny::ConnectionError, "Cannot connect to the specified server - host: #{@host}, port: #{@port}" if @insist
		
      @host, @port = method.host.split(':')
      close_socket
    else
      raise Bunny::ProtocolError, 'Cannot open connection'
    end
end

#qos(opts = {}) ⇒ Object

DESCRIPTION:

Requests a specific quality of service. The QoS can be specified for the current channel or for all channels on the connection. The particular properties and semantics of a QoS method always depend on the content class semantics. Though the QoS method could in principle apply to both peers, it is currently meaningful only for the server.

Options:

  • :prefetch_size => size in no. of octets (default = 0) - The client can request that

messages be sent in advance so that when the client finishes processing a message, the following message is already held locally, rather than needing to be sent down the channel. Prefetching gives a performance improvement. This field specifies the prefetch window size in octets. The server will send a message in advance if it is equal to or smaller in size than the available prefetch size (and also falls into other prefetch limits). May be set to zero, meaning “no specific limit”, although other prefetch limits may still apply. The prefetch-size is ignored if the no-ack option is set.

  • :prefetch_count => no. messages (default = 1) - Specifies a prefetch window in terms

of whole messages. This field may be used in combination with the prefetch-size field; a message will only be sent in advance if both prefetch windows (and those at the channel and connection level) allow it. The prefetch-count is ignored if the no-ack option is set.

  • :global => true or false (default) - By default the QoS settings apply to the current channel only. If set to

true, they are applied to the entire connection.

RETURNS:

:qos_ok if successful.



255
256
257
258
259
260
261
262
263
264
265
266
267
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 255

def qos(opts = {})

  send_frame(
    Qrack::Protocol::Basic::Qos.new({ :prefetch_size => 0, :prefetch_count => 1, :global => false }.merge(opts))
  )

			method = next_method
			
			check_response(method, Qrack::Protocol::Basic::QosOk, "Error specifying Quality of Service")

  # return confirmation
  :qos_ok
end

#queue(name = nil, opts = {}) ⇒ Object

DESCRIPTION:

Declares a queue to the broker/server. If the queue does not exist, a new one is created using the arguments passed in. If the queue already exists, a reference to it is created, provided that the arguments passed in do not conflict with the existing attributes of the queue. If an error occurs a Bunny::ProtocolError is raised.

OPTIONS:

  • :passive => true or false (default) - If set to true, the server will not create the queue. The client can use this to check whether a queue exists without modifying the server state.

  • :durable => true or false (default) - If set to true when creating a new queue, the queue will be marked as durable. Durable queues remain active when a server restarts. Non-durable queues (transient queues) are purged if/when a server restarts. Note that durable queues do not necessarily hold persistent messages, although it does not make sense to send persistent messages to a transient queue.

  • :exclusive => true or false (default) - If set to true, requests an exclusive queue. Exclusive queues may only be consumed from by the current connection. Setting the ‘exclusive’ flag always implies ‘auto-delete’.

  • :auto_delete => true or false (default) - If set to true, the queue is deleted when all consumers have finished using it. Last consumer can be cancelled either explicitly or because its channel is closed. If there has never been a consumer on the queue, it is not deleted.

  • :nowait => true or false (default) - Ignored by Bunny, always false.

RETURNS:

Queue



303
304
305
306
307
308
309
310
311
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 303

def queue(name = nil, opts = {})
   if name.is_a?(Hash)
     opts = name
     name = nil
   end

   # Queue is responsible for placing itself in the list of queues
   queues[name] || Bunny::Queue.new(self, name, opts)
end

#recover(opts = {}) ⇒ Object

DESCRIPTION:

Asks the broker to redeliver all unacknowledged messages on a specified channel. Zero or more messages may be redelivered.

Options:

  • :requeue => true or false (default) - If set to false, the message will be

redelivered to the original recipient. If set to true, the server will attempt to requeue the message, potentially then delivering it to an alternative subscriber.



328
329
330
331
332
333
334
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 328

def recover(opts = {})

  send_frame(
    Qrack::Protocol::Basic::Recover.new({ :requeue => false }.merge(opts))
  )

end

#request_access ⇒ Object 



336
337
338
339
340
341
342
343
344
345
346
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 336

def request_access
	send_frame(
      Qrack::Protocol::Access::Request.new(:realm => '/data', :read => true, :write => true, :active => true, :passive => true)
    )

    method = next_method
	
	check_response(method, Qrack::Protocol::Access::RequestOk, "Access denied")
    
    self.ticket = method.ticket
end

#send_frame(*args) ⇒ Object 



348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 348

def send_frame(*args)
  args.each do |data|
    data.ticket  = ticket if ticket and data.respond_to?(:ticket=)
    data         = data.to_frame(channel.number) unless data.is_a?(Qrack::Transport::Frame)
    data.channel = channel.number

    @logger.info("send") { data } if @logging
    write(data.to_s)

# Monitor client activity for heartbeat purposes
@message_out = true
  end

  nil
end

#send_heartbeat ⇒ Object 



364
365
366
367
368
369
370
371
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 364

def send_heartbeat
	# Create a new heartbeat frame
	hb = Qrack::Transport::Heartbeat.new('')		
	# Channel 0 must be used
	switch_channel(0) if @channel.number > 0			
	# Send the heartbeat to server
	send_frame(hb)
end

#start_session ⇒ Object Also known as: start

DESCRIPTION:

Opens a communication channel and starts a connection. If an error occurs, a Bunny::ProtocolError is raised. If successful, Client.status is set to :connected.

RETURNS:

:connected if successful.



386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 386

def start_session
			@connecting = true
			
  loop do
# Create/get socket
socket

# Initiate connection
init_connection

# Open connection
break if open_connection == :ok
  end

			# Open another channel because channel zero is used for specific purposes
			c = create_channel()
			c.open
			
			# Get access ticket
			request_access

			@connecting = false
			
			# return status
			@status = :connected
end

#tx_commit ⇒ Object

DESCRIPTION:

This method commits all messages published and acknowledged in the current transaction. A new transaction starts immediately after a commit.

RETURNS:

:commit_ok if successful.



428
429
430
431
432
433
434
435
436
437
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 428

def tx_commit
	send_frame(Qrack::Protocol::Tx::Commit.new())
	
	method = next_method
	
	check_response(method, Qrack::Protocol::Tx::CommitOk, "Error commiting transaction")

	# return confirmation
	:commit_ok
end

#tx_rollback ⇒ Object

DESCRIPTION:

This method abandons all messages published and acknowledged in the current transaction. A new transaction starts immediately after a rollback.

RETURNS:

:rollback_ok if successful.



452
453
454
455
456
457
458
459
460
461
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 452

def tx_rollback
	send_frame(Qrack::Protocol::Tx::Rollback.new())

	method = next_method
	
	check_response(method, Qrack::Protocol::Tx::RollbackOk, "Error rolling back transaction")

	# return confirmation
	:rollback_ok
end

#tx_select ⇒ Object

DESCRIPTION:

This method sets the channel to use standard transactions. The client must use this method at least once on a channel before using the Commit or Rollback methods.

RETURNS:

:select_ok if successful.



476
477
478
479
480
481
482
483
484
485
 
# File 'lib/ext/bunny-0.6.0/lib/bunny/client08.rb', line 476

def tx_select
	send_frame(Qrack::Protocol::Tx::Select.new())

	method = next_method
	
	check_response(method, Qrack::Protocol::Tx::SelectOk, "Error initiating transactions for current channel")

	# return confirmation
	:select_ok
end