lib/amqp/channel.rb in amqp-0.7.5 vs lib/amqp/channel.rb in amqp-0.8.0.beta1
- old
+ new
@@ -1,655 +1,633 @@
# encoding: utf-8
-require "amqp/collection"
+require "amqp/exchange"
+require "amqp/queue"
module AMQP
- # The top-level class for building AMQP clients. This class contains several
- # convenience methods for working with queues and exchanges. Many calls
- # delegate/forward to subclasses, but this is the preferred API. The subclass
- # API is subject to change while this high-level API will likely remain
- # unchanged as the library evolves. All code examples will be written using
- # the AMQP API.
+ # To quote {AMQP 0.9.1 specification http://bit.ly/hw2ELX}:
#
- # Below is a somewhat complex example that demonstrates several capabilities
- # of the library. The example starts a clock using a +fanout+ exchange which
- # is used for 1 to many communications. Each consumer generates a queue to
- # receive messages and do some operation (in this case, print the time).
- # One consumer prints messages every second while the second consumer prints
- # messages every 2 seconds. After 5 seconds has elapsed, the 1 second
- # consumer is deleted.
+ # AMQP is a multi-channelled protocol. Channels provide a way to multiplex
+ # a heavyweight TCP/IP connection into several light weight connections.
+ # This makes the protocol more “firewall friendly” since port usage is predictable.
+ # It also means that traffic shaping and other network QoS features can be easily employed.
+ # Channels are independent of each other and can perform different functions simultaneously
+ # with other channels, the available bandwidth being shared between the concurrent activities.
#
- # Of interest is the relationship of EventMachine to the process. All AMQP
- # operations must occur within the context of an EM.run block. We start
- # EventMachine in its own thread with an empty block; all subsequent calls
- # to the AMQP API add their blocks to the EM.run block. This demonstrates how
- # the library could be used to build up and tear down communications outside
- # the context of an EventMachine block and/or integrate the library with
- # other synchronous operations. See the EventMachine documentation for
- # more information.
#
- # require 'rubygems'
- # require 'mq'
+ # h2. RabbitMQ extensions.
#
- # thr = Thread.new { EM.run }
+ # AMQP gem supports several RabbitMQ extensions taht extend Channel functionality.
+ # Learn more in {file:docs/VendorSpecificExtensions.textile}
#
- # # turns on extreme logging
- # #AMQP.logging = true
#
- # def log *args
- # p args
- # end
+ # h2. Key methods
#
- # def publisher
- # clock = AMQP::Channel.fanout('clock')
- # EM.add_periodic_timer(1) do
- # puts
+ # Key methods of Channel class are
#
- # log :publishing, time = Time.now
- # clock.publish(Marshal.dump(time))
- # end
- # end
+ # * {Channel#queue}
+ # * {Channel#default_exchange}
+ # * {Channel#direct}
+ # * {Channel#fanout}
+ # * {Channel#topic}
+ # * {Channel#close}
#
- # def one_second_consumer
- # AMQP::Channel.queue('every second').bind(AMQP::Channel.fanout('clock')).subscribe do |time|
- # log 'every second', :received, Marshal.load(time)
- # end
- # end
+ # Channel provides a number of convenience methods that instantiate queues and exchanges
+ # of various types associated with this channel:
#
- # def two_second_consumer
- # AMQP::Channel.queue('every 2 seconds').bind('clock').subscribe do |time|
- # time = Marshal.load(time)
- # log 'every 2 seconds', :received, time if time.sec % 2 == 0
- # end
- # end
+ # * {Channel#queue}
+ # * {Channel#default_exchange}
+ # * {Channel#direct}
+ # * {Channel#fanout}
+ # * {Channel#topic}
#
- # def delete_one_second
- # EM.add_timer(5) do
- # # delete the 'every second' queue
- # log 'Deleting [every second] queue'
- # AMQP::Channel.queue('every second').delete
- # end
- # end
+ # Channels are opened when objects is instantiated and closed using {#close} method when application no longer
+ # needs it.
#
- # publisher
- # one_second_consumer
- # two_second_consumer
- # delete_one_second
- # thr.join
- #
- # __END__
- #
- # [:publishing, Tue Jan 06 22:46:14 -0600 2009]
- # ["every second", :received, Tue Jan 06 22:46:14 -0600 2009]
- # ["every 2 seconds", :received, Tue Jan 06 22:46:14 -0600 2009]
- #
- # [:publishing, Tue Jan 06 22:46:16 -0600 2009]
- # ["every second", :received, Tue Jan 06 22:46:16 -0600 2009]
- # ["every 2 seconds", :received, Tue Jan 06 22:46:16 -0600 2009]
- #
- # [:publishing, Tue Jan 06 22:46:17 -0600 2009]
- # ["every second", :received, Tue Jan 06 22:46:17 -0600 2009]
- #
- # [:publishing, Tue Jan 06 22:46:18 -0600 2009]
- # ["every second", :received, Tue Jan 06 22:46:18 -0600 2009]
- # ["every 2 seconds", :received, Tue Jan 06 22:46:18 -0600 2009]
- # ["Deleting [every second] queue"]
- #
- # [:publishing, Tue Jan 06 22:46:19 -0600 2009]
- #
- # [:publishing, Tue Jan 06 22:46:20 -0600 2009]
- # ["every 2 seconds", :received, Tue Jan 06 22:46:20 -0600 2009]
- #
- class Channel
+ # @see http://bit.ly/hw2ELX AMQP 0.9.1 specification (Section 2.2.5)
+ class Channel < AMQ::Client::Channel
#
- # Behaviors
+ # API
#
- include EM::Deferrable
+ # AMQP connection this channel is part of
+ # @return [Connection]
+ attr_reader :connection
+ alias :conn :connection
+ # Status of this channel (one of: :opening, :closing, :open, :closed)
+ # @return [Symbol]
+ attr_reader :status
+ # @note We encourage you to not rely on default AMQP connection and pass connection parameter
+ # explicitly.
#
- # API
+ # @param [AMQ::Client::EventMachineAdapter] Connection to open this channel on. If not given, default AMQP
+ # connection (accessible via {AMQP.connection}) will be used.
+ # @param [Integer] Channel id. Must not be greater than max channel id client and broker
+ # negotiated on during connection setup. Almost always the right thing to do
+ # is to let AMQP gem pick channel identifier for you.
#
-
- # Returns a new channel. A channel is a bidirectional virtual
- # connection between the client and the AMQP server. Elsewhere in the
- # library the channel is referred to in parameter lists as +mq+.
+ # @example Instantiating a channel for default connection (accessible as AMQP.connection)
#
- # Optionally takes the result from calling AMQP::connect.
+ # AMQP.connect do |connection|
+ # AMQP::Channel.new(connection) do |channel|
+ # # channel is ready: set up your messaging flow by creating exchanges,
+ # # queues, binding them together and so on.
+ # end
+ # end
#
- # Rarely called directly by client code. This is implicitly called
- # by most instance methods. See #method_missing.
+ # @example Instantiating a channel for explicitly given connection
#
- # EM.run do
- # channel = AMQP::Channel.new
- # end
+ # AMQP.connect do |connection|
+ # AMQP::Channel.new(connection) do |channel|
+ # # channel is ready: set up your messaging flow by creating exchanges,
+ # # queues, binding them together and so on.
+ # end
+ # end
#
- # EM.run do
- # channel = AMQP::Channel.new AMQP::connect
- # end
#
- def initialize(connection = nil)
+ # @yield [channel, open_ok] Yields open channel instance and AMQP method (channel.open-ok) instance. The latter is optional.
+ # @yieldparam [Channel] channel Channel that is successfully open
+ # @yieldparam [AMQP::Protocol::Channel::OpenOk] open_ok AMQP channel.open-ok) instance
+ #
+ #
+ # @api public
+ def initialize(connection = nil, id = self.class.next_channel_id, &block)
raise 'AMQP can only be used from within EM.run {}' unless EM.reactor_running?
- @_send_mutex = Mutex.new
- @get_queue_mutex = Mutex.new
-
@connection = connection || AMQP.start
- @queues_awaiting_declare_ok = Array.new
+ super(@connection, id)
- conn.callback { |c|
- @channel = c.add_channel(self)
- send Protocol::Channel::Open.new
- }
- end
+ @rpcs = Hash.new
+ # we need this deferrable to mimic what AMQP gem 0.7 does to enable
+ # the following (HIGHLY discouraged) style of programming some people use in their
+ # existing codebases:
+ #
+ # connection = AMQP.connect
+ # channel = AMQP::Channel.new(connection)
+ # queue = AMQP::Queue.new(channel)
+ #
+ # ...
+ #
+ # Read more about EM::Deferrable#callback behavior in EventMachine documentation. MK.
+ @channel_is_open_deferrable = AMQ::Client::EventMachineClient::Deferrable.new
- attr_reader :channel, :connection, :status
- alias :conn :connection
+ # only send channel.open when connection is actually open. Makes it possible to
+ # do c = AMQP.connect; AMQP::Channel.new(c) that is what some people do. MK.
+ @connection.on_open do
+ self.open do |*args|
+ @channel_is_open_deferrable.succeed
- attr_reader :queues_awaiting_declare_ok
+ block.call(*args) if block
+ end
+ end
+ end
+ def once_open(&block)
+ @channel_is_open_deferrable.callback(&block)
+ end # once_open(&block)
- def closed?
- @status.eql?(:closed)
- end
- def open?
- !self.closed?
- end # open?
-
- # Defines, intializes and returns an Exchange to act as an ingress
- # point for all published messages.
+ # Defines, intializes and returns a direct Exchange instance.
#
- # == Direct
- # A direct exchange is useful for 1:1 communication between a publisher and
- # subscriber. Messages are routed to the queue with a binding that shares
- # the same name as the exchange. Alternately, the messages are routed to
- # the bound queue that shares the same name as the routing key used for
- # defining the exchange. This exchange type does not honor the +:key+ option
- # when defining a new instance with a name. It _will_ honor the +:key+ option
- # if the exchange name is the empty string.
- # Allocating this exchange without a name _or_ with the empty string
- # will use the internal 'amq.direct' exchange.
+ # Learn more about direct exchanges in {Exchange Exchange class documentation}.
#
- # Any published message, regardless of its persistence setting, is thrown
- # away by the exchange when there are no queues bound to it.
#
- # # exchange is named 'foo'
- # exchange = AMQP::Channel.direct('foo')
+ # @param [String] name (amq.direct) Exchange name.
#
- # # or, the exchange can use the default name (amq.direct) and perform
- # # routing comparisons using the :key
- # exchange = AMQP::Channel.direct("", :key => 'foo')
- # exchange.publish('some data') # will be delivered to queue bound to 'foo'
+ # @option opts [Boolean] :passive (false) If set, the server will not create the exchange if it does not
+ # already exist. The client can use this to check whether an exchange
+ # exists without modifying the server state.
#
- # queue = AMQP::Channel.queue('foo')
- # # can receive data since the queue name and the exchange key match exactly
- # queue.pop { |data| puts "received data [#{data}]" }
+ # @option opts [Boolean] :durable (false) If set when creating a new exchange, the exchange will be marked as
+ # durable. Durable exchanges and their bindings are recreated upon a server
+ # restart (information about them is persisted). Non-durable (transient) exchanges
+ # do not survive if/when a server restarts (information about them is stored exclusively
+ # in RAM).
#
- # == Options
- # * :passive => true | false (default false)
- # If set, the server will not create the exchange if it does not
- # already exist. The client can use this to check whether an exchange
- # exists without modifying the server state.
#
- # * :durable => true | false (default false)
- # If set 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.
+ # @option opts [Boolean] :auto_delete (false) If set, the exchange is deleted when all queues have finished
+ # using it. The server waits for a short period of time before
+ # determining the exchange is unused to give time to the client code
+ # to bind a queue to it.
#
- # A transient exchange (the default) is stored in memory-only. The
- # exchange and all bindings will be lost on a server restart.
- # It makes no sense to publish a persistent message to a transient
- # exchange.
+ # @option opts [Boolean] :internal (default false) If set, the exchange may not be used directly by publishers, but
+ # only when bound to other exchanges. Internal exchanges are used to
+ # construct wiring that is not visible to applications. This is a RabbitMQ-specific
+ # extension.
#
- # Durable exchanges and their bindings are recreated upon a server
- # restart. Any published messages not routed to a bound queue are lost.
+ # @option opts [Boolean] :nowait (true) If set, the server will not respond to the method. The client should
+ # not wait for a reply method. If the server could not complete the
+ # method it will raise a channel or connection exception.
#
- # * :auto_delete => true | false (default false)
- # If set, the exchange is deleted when all queues have finished
- # using it. The server waits for a short period of time before
- # determining the exchange is unused to give time to the client code
- # to bind a queue to it.
#
- # If the exchange has been previously declared, this option is ignored
- # on subsequent declarations.
+ # @raise [AMQP::Error] Raised when exchange is redeclared with parameters different from original declaration.
+ # @raise [AMQP::Error] Raised when exchange is declared with :passive => true and the exchange does not exist.
#
- # * :internal => true | false (default false)
- # If set, the exchange may not be used directly by publishers, but
- # only when bound to other exchanges. Internal exchanges are used to
- # construct wiring that is not visible to applications.
#
- # * :nowait => true | false (default true)
- # If set, the server will not respond to the method. The client should
- # not wait for a reply method. If the server could not complete the
- # method it will raise a channel or connection exception.
+ # @example Using default pre-declared direct exchange and no callbacks (pseudo-synchronous style)
#
- # == Exceptions
- # Doing any of these activities are illegal and will raise AMQP::Error.
- # * redeclare an already-declared exchange to a different type
- # * :passive => true and the exchange does not exist (NOT_FOUND)
+ # # an exchange application A will be using to publish updates
+ # # to some search index
+ # exchange = channel.direct("index.updates")
#
+ # # In the same (or different) process declare a queue that broker will
+ # # generate name for, bind it to aforementioned exchange using method chaining
+ # queue = channel.queue("").
+ # # queue will be receiving messages that were published with
+ # # :routing_key attribute value of "search.index.updates"
+ # bind(exchange, :routing_key => "search.index.updates").
+ # # register a callback that will be run when messages arrive
+ # subscribe { |header, message| puts("Received #{message}") }
+ #
+ # # now publish a new document contents for indexing,
+ # # message will be delivered to the queue we declared and bound on the line above
+ # exchange.publish(document.content, :routing_key => "search.index.updates")
+ #
+ #
+ # @example Instantiating a direct exchange using {Channel#direct} with a callback
+ #
+ # AMQP.connect do |connection|
+ # AMQP::Channel.new(connection) do |channel|
+ # channel.direct("email.replies_listener") do |exchange, declare_ok|
+ # # by now exchange is ready and waiting
+ # end
+ # end
+ # end
+ #
+ #
+ # @see Channel#default_exchange
+ # @see Exchange
+ # @see Exchange#initialize
+ # @see http://bit.ly/hw2ELX AMQP 0.9.1 specification (Section 3.1.3.1)
+ #
+ # @return [Exchange]
+ # @api public
def direct(name = 'amq.direct', opts = {}, &block)
- if exchange = self.exchanges.find { |exchange| exchange.name == name }
+ if exchange = find_exchange(name)
extended_opts = Exchange.add_default_options(:direct, name, opts, block)
validate_parameters_match!(exchange, extended_opts)
exchange
else
- self.exchanges << Exchange.new(self, :direct, name, opts, &block)
+ register_exchange(Exchange.new(self, :direct, name, opts, &block))
end
end
# Returns exchange object with the same name as default (aka unnamed) exchange.
# Default exchange is a direct exchange and automatically routes messages to
# queues when routing key matches queue name exactly. This feature is known as
# "automatic binding" (of queues to default exchange).
#
# *Use default exchange when you want to route messages directly to specific queues*
# (queue names are known, you don't mind this kind of coupling between applications).
+ #
+ #
+ # @example Using default exchange to publish messages to queues with known names
+ # AMQP.start(:host => 'localhost') do |connection|
+ # ch = AMQP::Channel.new(connection)
+ #
+ # queue1 = ch.queue("queue1").subscribe do |payload|
+ # puts "[#{queue1.name}] => #{payload}"
+ # end
+ # queue2 = ch.queue("queue2").subscribe do |payload|
+ # puts "[#{queue2.name}] => #{payload}"
+ # end
+ # queue3 = ch.queue("queue3").subscribe do |payload|
+ # puts "[#{queue3.name}] => #{payload}"
+ # end
+ # queues = [queue1, queue2, queue3]
+ #
+ # # Rely on default direct exchange binding, see section 2.1.2.4 Automatic Mode in AMQP 0.9.1 spec.
+ # exchange = AMQP::Exchange.default
+ # EM.add_periodic_timer(1) do
+ # q = queues.sample
+ #
+ # exchange.publish "Some payload from #{Time.now.to_i}", :routing_key => q.name
+ # end
+ # end
+ #
+ #
+ #
+ # @see Exchange
+ # @see http://bit.ly/hw2ELX AMQP 0.9.1 specification (Section 2.1.2.4)
+ #
+ # @return [Exchange]
+ # @api public
def default_exchange
Exchange.default(self)
end
-
- # Defines, intializes and returns an Exchange to act as an ingress
- # point for all published messages.
+ # Defines, intializes and returns a fanout Exchange instance.
#
- # == Fanout
- # A fanout exchange is useful for 1:N communication where one publisher
- # feeds multiple subscribers. Like direct exchanges, messages published
- # to a fanout exchange are delivered to queues whose name matches the
- # exchange name (or are bound to that exchange name). Each queue gets
- # its own copy of the message.
+ # Learn more about fanout exchanges in {Exchange Exchange class documentation}.
#
- # Any published message, regardless of its persistence setting, is thrown
- # away by the exchange when there are no queues bound to it.
#
- # Like the direct exchange type, this exchange type does not honor the
- # +:key+ option when defining a new instance with a name. It _will_ honor
- # the +:key+ option if the exchange name is the empty string.
- # Allocating this exchange without a name _or_ with the empty string
- # will use the internal 'amq.fanout' exchange.
+ # @param [String] name (amq.fanout) Exchange name.
#
- # EM.run do
- # clock = AMQP::Channel.fanout('clock')
- # EM.add_periodic_timer(1) do
- # puts "\npublishing #{time = Time.now}"
- # clock.publish(Marshal.dump(time))
- # end
+ # @option opts [Boolean] :passive (false) If set, the server will not create the exchange if it does not
+ # already exist. The client can use this to check whether an exchange
+ # exists without modifying the server state.
#
- # amq = AMQP::Channel.queue('every second')
- # amq.bind(AMQP::Channel.fanout('clock')).subscribe do |time|
- # puts "every second received #{Marshal.load(time)}"
- # end
+ # @option opts [Boolean] :durable (false) If set when creating a new exchange, the exchange will be marked as
+ # durable. Durable exchanges and their bindings are recreated upon a server
+ # restart (information about them is persisted). Non-durable (transient) exchanges
+ # do not survive if/when a server restarts (information about them is stored exclusively
+ # in RAM).
#
- # # note the string passed to #bind
- # AMQP::Channel.queue('every 5 seconds').bind('clock').subscribe do |time|
- # time = Marshal.load(time)
- # puts "every 5 seconds received #{time}" if time.strftime('%S').to_i%5 == 0
- # end
- # end
#
- # == Options
- # * :passive => true | false (default false)
- # If set, the server will not create the exchange if it does not
- # already exist. The client can use this to check whether an exchange
- # exists without modifying the server state.
+ # @option opts [Boolean] :auto_delete (false) If set, the exchange is deleted when all queues have finished
+ # using it. The server waits for a short period of time before
+ # determining the exchange is unused to give time to the client code
+ # to bind a queue to it.
#
- # * :durable => true | false (default false)
- # If set 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.
+ # @option opts [Boolean] :internal (default false) If set, the exchange may not be used directly by publishers, but
+ # only when bound to other exchanges. Internal exchanges are used to
+ # construct wiring that is not visible to applications. This is a RabbitMQ-specific
+ # extension.
#
- # A transient exchange (the default) is stored in memory-only. The
- # exchange and all bindings will be lost on a server restart.
- # It makes no sense to publish a persistent message to a transient
- # exchange.
+ # @option opts [Boolean] :nowait (true) If set, the server will not respond to the method. The client should
+ # not wait for a reply method. If the server could not complete the
+ # method it will raise a channel or connection exception.
#
- # Durable exchanges and their bindings are recreated upon a server
- # restart. Any published messages not routed to a bound queue are lost.
#
- # * :auto_delete => true | false (default false)
- # If set, the exchange is deleted when all queues have finished
- # using it. The server waits for a short period of time before
- # determining the exchange is unused to give time to the client code
- # to bind a queue to it.
+ # @raise [AMQP::Error] Raised when exchange is redeclared with parameters different from original declaration.
+ # @raise [AMQP::Error] Raised when exchange is declared with :passive => true and the exchange does not exist.
#
- # If the exchange has been previously declared, this option is ignored
- # on subsequent declarations.
#
- # * :internal => true | false (default false)
- # If set, the exchange may not be used directly by publishers, but
- # only when bound to other exchanges. Internal exchanges are used to
- # construct wiring that is not visible to applications.
+ # @example Using fanout exchange to deliver messages to multiple consumers
#
- # * :nowait => true | false (default true)
- # If set, the server will not respond to the method. The client should
- # not wait for a reply method. If the server could not complete the
- # method it will raise a channel or connection exception.
+ # # open up a channel
+ # # declare a fanout exchange
+ # # declare 3 queues, binds them
+ # # publish a message
#
- # == Exceptions
- # Doing any of these activities are illegal and will raise AMQP::Error.
- # * redeclare an already-declared exchange to a different type
- # * :passive => true and the exchange does not exist (NOT_FOUND)
+ # @see Exchange
+ # @see Exchange#initialize
+ # @see Channel#default_exchange
+ # @see http://bit.ly/hw2ELX AMQP 0.9.1 specification (Section 3.1.3.2)
#
+ # @return [Exchange]
+ # @api public
def fanout(name = 'amq.fanout', opts = {}, &block)
- if exchange = self.exchanges.find { |exchange| exchange.name == name }
+ if exchange = find_exchange(name)
extended_opts = Exchange.add_default_options(:fanout, name, opts, block)
validate_parameters_match!(exchange, extended_opts)
exchange
else
- self.exchanges << Exchange.new(self, :fanout, name, opts, &block)
+ register_exchange(Exchange.new(self, :fanout, name, opts, &block))
end
end
- # Defines, intializes and returns an Exchange to act as an ingress
- # point for all published messages.
+
+ # Defines, intializes and returns a topic Exchange instance.
#
- # == Topic
- # A topic exchange allows for messages to be published to an exchange
- # tagged with a specific routing key. The Exchange uses the routing key
- # to determine which queues to deliver the message. Wildcard matching
- # is allowed. The topic must be declared using dot notation to separate
- # each subtopic.
+ # Learn more about topic exchanges in {Exchange Exchange class documentation}.
#
- # This is the only exchange type to honor the +key+ hash key for all
- # cases.
+ # @param [String] name (amq.topic) Exchange name.
#
- # Any published message, regardless of its persistence setting, is thrown
- # away by the exchange when there are no queues bound to it.
#
- # As part of the AMQP standard, each server _should_ predeclare a topic
- # exchange called 'amq.topic' (this is not required by the standard).
- # Allocating this exchange without a name _or_ with the empty string
- # will use the internal 'amq.topic' exchange.
+ # @option opts [Boolean] :passive (false) If set, the server will not create the exchange if it does not
+ # already exist. The client can use this to check whether an exchange
+ # exists without modifying the server state.
#
- # The classic example is delivering market data. When publishing market
- # data for stocks, we may subdivide the stream based on 2
- # characteristics: nation code and trading symbol. The topic tree for
- # Apple Computer would look like:
- # 'stock.us.aapl'
- # For a foreign stock, it may look like:
- # 'stock.de.dax'
+ # @option opts [Boolean] :durable (false) If set when creating a new exchange, the exchange will be marked as
+ # durable. Durable exchanges and their bindings are recreated upon a server
+ # restart (information about them is persisted). Non-durable (transient) exchanges
+ # do not survive if/when a server restarts (information about them is stored exclusively
+ # in RAM).
#
- # When publishing data to the exchange, bound queues subscribing to the
- # exchange indicate which data interests them by passing a routing key
- # for matching against the published routing key.
#
- # EM.run do
- # exch = AMQP::Channel.topic("stocks")
- # keys = ['stock.us.aapl', 'stock.de.dax']
+ # @option opts [Boolean] :auto_delete (false) If set, the exchange is deleted when all queues have finished
+ # using it. The server waits for a short period of time before
+ # determining the exchange is unused to give time to the client code
+ # to bind a queue to it.
#
- # EM.add_periodic_timer(1) do # every second
- # puts
- # exch.publish(10+rand(10), :routing_key => keys[rand(2)])
- # end
+ # @option opts [Boolean] :internal (default false) If set, the exchange may not be used directly by publishers, but
+ # only when bound to other exchanges. Internal exchanges are used to
+ # construct wiring that is not visible to applications. This is a RabbitMQ-specific
+ # extension.
#
- # # match against one dot-separated item
- # AMQP::Channel.queue('us stocks').bind(exch, :key => 'stock.us.*').subscribe do |price|
- # puts "us stock price [#{price}]"
- # end
+ # @option opts [Boolean] :nowait (true) If set, the server will not respond to the method. The client should
+ # not wait for a reply method. If the server could not complete the
+ # method it will raise a channel or connection exception.
#
- # # match against multiple dot-separated items
- # AMQP::Channel.queue('all stocks').bind(exch, :key => 'stock.#').subscribe do |price|
- # puts "all stocks: price [#{price}]"
- # end
#
- # # require exact match
- # AMQP::Channel.queue('only dax').bind(exch, :key => 'stock.de.dax').subscribe do |price|
- # puts "dax price [#{price}]"
- # end
- # end
+ # @raise [AMQP::Error] Raised when exchange is redeclared with parameters different from original declaration.
+ # @raise [AMQP::Error] Raised when exchange is declared with :passive => true and the exchange does not exist.
#
- # For matching, the '*' (asterisk) wildcard matches against one
- # dot-separated item only. The '#' wildcard (hash or pound symbol)
- # matches against 0 or more dot-separated items. If none of these
- # symbols are used, the exchange performs a comparison looking for an
- # exact match.
#
- # == Options
- # * :passive => true | false (default false)
- # If set, the server will not create the exchange if it does not
- # already exist. The client can use this to check whether an exchange
- # exists without modifying the server state.
+ # @example Using topic exchange to deliver relevant news updates
+ # AMQP.connect do |connection|
+ # channel = AMQP::Channel.new(connection)
+ # exchange = channel.topic("pub/sub")
#
- # * :durable => true | false (default false)
- # If set 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.
+ # # Subscribers.
+ # channel.queue("development").bind(exchange, :key => "technology.dev.#").subscribe do |payload|
+ # puts "A new dev post: '#{payload}'"
+ # end
+ # channel.queue("ruby").bind(exchange, :key => "technology.#.ruby").subscribe do |payload|
+ # puts "A new post about Ruby: '#{payload}'"
+ # end
#
- # A transient exchange (the default) is stored in memory-only. The
- # exchange and all bindings will be lost on a server restart.
- # It makes no sense to publish a persistent message to a transient
- # exchange.
+ # # Let's publish some data.
+ # exchange.publish "Ruby post", :routing_key => "technology.dev.ruby"
+ # exchange.publish "Erlang post", :routing_key => "technology.dev.erlang"
+ # exchange.publish "Sinatra post", :routing_key => "technology.web.ruby"
+ # exchange.publish "Jewelery post", :routing_key => "jewelery.ruby"
+ # end
#
- # Durable exchanges and their bindings are recreated upon a server
- # restart. Any published messages not routed to a bound queue are lost.
#
- # * :auto_delete => true | false (default false)
- # If set, the exchange is deleted when all queues have finished
- # using it. The server waits for a short period of time before
- # determining the exchange is unused to give time to the client code
- # to bind a queue to it.
+ # @example Using topic exchange to deliver geographically-relevant data
+ # AMQP.connect do |connection|
+ # channel = AMQP::Channel.new(connection)
+ # exchange = channel.topic("pub/sub")
#
- # If the exchange has been previously declared, this option is ignored
- # on subsequent declarations.
+ # # Subscribers.
+ # channel.queue("americas.north").bind(exchange, :routing_key => "americas.north.#").subscribe do |headers, payload|
+ # puts "An update for North America: #{payload}, routing key is #{headers.routing_key}"
+ # end
+ # channel.queue("americas.south").bind(exchange, :routing_key => "americas.south.#").subscribe do |headers, payload|
+ # puts "An update for South America: #{payload}, routing key is #{headers.routing_key}"
+ # end
+ # channel.queue("us.california").bind(exchange, :routing_key => "americas.north.us.ca.*").subscribe do |headers, payload|
+ # puts "An update for US/California: #{payload}, routing key is #{headers.routing_key}"
+ # end
+ # channel.queue("us.tx.austin").bind(exchange, :routing_key => "#.tx.austin").subscribe do |headers, payload|
+ # puts "An update for Austin, TX: #{payload}, routing key is #{headers.routing_key}"
+ # end
+ # channel.queue("it.rome").bind(exchange, :routing_key => "europe.italy.rome").subscribe do |headers, payload|
+ # puts "An update for Rome, Italy: #{payload}, routing key is #{headers.routing_key}"
+ # end
+ # channel.queue("asia.hk").bind(exchange, :routing_key => "asia.southeast.hk.#").subscribe do |headers, payload|
+ # puts "An update for Hong Kong: #{payload}, routing key is #{headers.routing_key}"
+ # end
#
- # * :internal => true | false (default false)
- # If set, the exchange may not be used directly by publishers, but
- # only when bound to other exchanges. Internal exchanges are used to
- # construct wiring that is not visible to applications.
+ # exchange.publish("San Diego update", :routing_key => "americas.north.us.ca.sandiego").
+ # publish("Berkeley update", :routing_key => "americas.north.us.ca.berkeley").
+ # publish("San Francisco update", :routing_key => "americas.north.us.ca.sanfrancisco").
+ # publish("New York update", :routing_key => "americas.north.us.ny.newyork").
+ # publish("São Paolo update", :routing_key => "americas.south.brazil.saopaolo").
+ # publish("Hong Kong update", :routing_key => "asia.southeast.hk.hongkong").
+ # publish("Kyoto update", :routing_key => "asia.southeast.japan.kyoto").
+ # publish("Shanghai update", :routing_key => "asia.southeast.prc.shanghai").
+ # publish("Rome update", :routing_key => "europe.italy.roma").
+ # publish("Paris update", :routing_key => "europe.france.paris")
+ # end
#
- # * :nowait => true | false (default true)
- # If set, the server will not respond to the method. The client should
- # not wait for a reply method. If the server could not complete the
- # method it will raise a channel or connection exception.
+ # @see Exchange
+ # @see Exchange#initialize
+ # @see http://www.rabbitmq.com/faq.html#Binding-and-Routing RabbitMQ FAQ on routing & wildcards
+ # @see http://bit.ly/hw2ELX AMQP 0.9.1 specification (Section 3.1.3.3)
#
- # == Exceptions
- # Doing any of these activities are illegal and will raise AMQP::Error.
- # * redeclare an already-declared exchange to a different type
- # * :passive => true and the exchange does not exist (NOT_FOUND)
- #
+ # @return [Exchange]
+ # @api public
def topic(name = 'amq.topic', opts = {}, &block)
- if exchange = self.exchanges.find { |exchange| exchange.name == name }
+ if exchange = find_exchange(name)
extended_opts = Exchange.add_default_options(:topic, name, opts, block)
validate_parameters_match!(exchange, extended_opts)
exchange
else
- self.exchanges << Exchange.new(self, :topic, name, opts, &block)
+ register_exchange(Exchange.new(self, :topic, name, opts, &block))
end
end
- # Defines, intializes and returns an Exchange to act as an ingress
- # point for all published messages.
+
+ # Defines, intializes and returns a headers Exchange instance.
#
- # == Headers
- # A headers exchange allows for messages to be published to an exchange
+ # Learn more about headers exchanges in {Exchange Exchange class documentation}.
#
- # Any published message, regardless of its persistence setting, is thrown
- # away by the exchange when there are no queues bound to it.
+ # @param [String] name (amq.match) Exchange name.
#
- # As part of the AMQP standard, each server _should_ predeclare a headers
- # exchange called 'amq.match' (this is not required by the standard).
- # Allocating this exchange without a name _or_ with the empty string
- # will use the internal 'amq.match' exchange.
+ # @option opts [Boolean] :passive (false) If set, the server will not create the exchange if it does not
+ # already exist. The client can use this to check whether an exchange
+ # exists without modifying the server state.
#
- # TODO: The classic example is ...
+ # @option opts [Boolean] :durable (false) If set when creating a new exchange, the exchange will be marked as
+ # durable. Durable exchanges and their bindings are recreated upon a server
+ # restart (information about them is persisted). Non-durable (transient) exchanges
+ # do not survive if/when a server restarts (information about them is stored exclusively
+ # in RAM).
#
- # When publishing data to the exchange, bound queues subscribing to the
- # exchange indicate which data interests them by passing arguments
- # for matching against the headers in published messages. The
- # form of the matching can be controlled by the 'x-match' argument, which
- # may be 'any' or 'all'. If unspecified (in RabbitMQ at least), it defaults
- # to "all".
#
- # A value of 'all' for 'x-match' implies that all values must match (i.e.
- # it does an AND of the headers ), while a value of 'any' implies that
- # at least one should match (ie. it does an OR).
+ # @option opts [Boolean] :auto_delete (false) If set, the exchange is deleted when all queues have finished
+ # using it. The server waits for a short period of time before
+ # determining the exchange is unused to give time to the client code
+ # to bind a queue to it.
#
- # TODO: document behavior when either the binding or the message is missing
- # a header present in the other
+ # @option opts [Boolean] :internal (default false) If set, the exchange may not be used directly by publishers, but
+ # only when bound to other exchanges. Internal exchanges are used to
+ # construct wiring that is not visible to applications. This is a RabbitMQ-specific
+ # extension.
#
- # TODO: insert example
+ # @option opts [Boolean] :nowait (true) If set, the server will not respond to the method. The client should
+ # not wait for a reply method. If the server could not complete the
+ # method it will raise a channel or connection exception.
#
- # == Options
- # * :passive => true | false (default false)
- # If set, the server will not create the exchange if it does not
- # already exist. The client can use this to check whether an exchange
- # exists without modifying the server state.
#
- # * :durable => true | false (default false)
- # If set 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.
+ # @raise [AMQP::Error] Raised when exchange is redeclared with parameters different from original declaration.
+ # @raise [AMQP::Error] Raised when exchange is declared with :passive => true and the exchange does not exist.
#
- # A transient exchange (the default) is stored in memory-only. The
- # exchange and all bindings will be lost on a server restart.
- # It makes no sense to publish a persistent message to a transient
- # exchange.
#
- # Durable exchanges and their bindings are recreated upon a server
- # restart. Any published messages not routed to a bound queue are lost.
+ # @example Using fanout exchange to deliver messages to multiple consumers
#
- # * :auto_delete => true | false (default false)
- # If set, the exchange is deleted when all queues have finished
- # using it. The server waits for a short period of time before
- # determining the exchange is unused to give time to the client code
- # to bind a queue to it.
+ # # TODO
#
- # If the exchange has been previously declared, this option is ignored
- # on subsequent declarations.
#
- # * :internal => true | false (default false)
- # If set, the exchange may not be used directly by publishers, but
- # only when bound to other exchanges. Internal exchanges are used to
- # construct wiring that is not visible to applications.
+ # @see Exchange
+ # @see Exchange#initialize
+ # @see Channel#default_exchange
+ # @see http://bit.ly/hw2ELX AMQP 0.9.1 specification (Section 3.1.3.3)
#
- # * :nowait => true | false (default true)
- # If set, the server will not respond to the method. The client should
- # not wait for a reply method. If the server could not complete the
- # method it will raise a channel or connection exception.
- #
- # == Exceptions
- # Doing any of these activities are illegal and will raise AMQP::Error.
- # * redeclare an already-declared exchange to a different type
- # * :passive => true and the exchange does not exist (NOT_FOUND)
- # * using a value other than "any" or "all" for "x-match"
+ # @return [Exchange]
+ # @api public
def headers(name = 'amq.match', opts = {}, &block)
- if exchange = self.exchanges.find { |exchange| exchange.name == name }
+ if exchange = find_exchange(name)
extended_opts = Exchange.add_default_options(:headers, name, opts, block)
validate_parameters_match!(exchange, extended_opts)
exchange
else
- self.exchanges << Exchange.new(self, :headers, name, opts, &block)
+ register_exchange(Exchange.new(self, :headers, name, opts, &block))
end
end
- # Queues store and forward messages. Queues can be configured in the server
- # or created at runtime. Queues must be attached to at least one exchange
- # in order to receive messages from publishers.
+
+ # Declares and returns a Queue instance associated with this channel. See {Queue Queue class documentation} for
+ # more information about queues.
#
- # Like an Exchange, queue names starting with 'amq.' are reserved for
- # internal use. Attempts to create queue names in violation of this
- # reservation will raise AMQP::Error (ACCESS_REFUSED).
+ # To make broker generate queue name for you (a classic example is exclusive
+ # queues that are only used for a short period of time), pass empty string
+ # as name value. Then queue will get it's name as soon as broker's response
+ # (queue.declare-ok) arrives. Note that in this case, block is required.
#
- # It is not supported to create a queue without a name; some string
- # (even the empty string) must be passed in the +name+ parameter.
#
- # == Options
- # * :passive => true | false (default false)
- # If set, the server will not create the queue if it does not
- # already exist. The client can use this to check whether the queue
- # exists without modifying the server state.
+ # Like for exchanges, queue names starting with 'amq.' cannot be modified and
+ # should not be used by applications.
#
- # * :durable => true | false (default false)
- # If set 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 (though it is
- # allowed).
+ # @example Declaring a queue in a mail delivery app using Channel#queue without a block
+ # AMQP.connect do |connection|
+ # AMQP::Channel.new(connection) do |ch|
+ # # message producers will be able to send messages to this queue
+ # # using direct exchange and routing key = "mail.delivery"
+ # queue = ch.queue("mail.delivery", :durable => true)
+ # queue.subscribe do |headers, payload|
+ # # ...
+ # end
+ # end
+ # end
#
- # Again, note the durability property on a queue has no influence on
- # the persistence of published messages. A durable queue containing
- # transient messages will flush those messages on a restart.
+ # @example Declaring a server-named exclusive queue that receives all messages related to events, using a block.
+ # AMQP.connect do |connection|
+ # AMQP::Channel.new(connection) do |ch|
+ # # message producers will be able to send messages to this queue
+ # # using amq.topic exchange with routing keys that begin with "events"
+ # ch.queue("", :exclusive => true) do |queue|
+ # queue.bind(ch.exchange("amq.topic"), :routing_key => "events.#").subscribe do |headers, payload|
+ # # ...
+ # end
+ # end
+ # end
+ # end
#
- # If the queue has already been declared, any redeclaration will
- # ignore this setting. A queue may only be declared durable the
- # first time when it is created.
+ # @param [String] name Queue name. If you want a server-named queue, you can omit the name (note that in this case, using block is mandatory).
+ # See {Queue Queue class documentation} for discussion of queue lifecycles and when use of server-named queues
+ # is optimal.
#
- # * :exclusive => true | false (default false)
- # Exclusive queues may only be consumed from by the current connection.
- # Setting the 'exclusive' flag always implies 'auto-delete'. Only a
- # single consumer is allowed to remove messages from this queue.
+ # @option opts [Boolean] :passive (false) If set, the server will not create the exchange if it does not
+ # already exist. The client can use this to check whether an exchange
+ # exists without modifying the server state.
#
- # The default is a shared queue. Multiple clients may consume messages
- # from this queue.
+ # @option opts [Boolean] :durable (false) If set when creating a new exchange, the exchange will be marked as
+ # durable. Durable exchanges and their bindings are recreated upon a server
+ # restart (information about them is persisted). Non-durable (transient) exchanges
+ # do not survive if/when a server restarts (information about them is stored exclusively
+ # in RAM). Any remaining messages in the queue will be purged when the queue
+ # is deleted regardless of the message's persistence setting.
#
- # Attempting to redeclare an already-declared queue as :exclusive => true
- # will raise AMQP::Error.
#
- # * :auto_delete = true | false (default false)
- # If set, 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 was no consumer ever on the queue, it
- # won't be deleted.
+ # @option opts [Boolean] :auto_delete (false) If set, the exchange is deleted when all queues have finished
+ # using it. The server waits for a short period of time before
+ # determining the exchange is unused to give time to the client code
+ # to bind a queue to it.
#
- # The server waits for a short period of time before
- # determining the queue is unused to give time to the client code
- # to bind a queue to it.
+ # @option opts [Boolean] :exclusive (false) Exclusive queues may only be used by a single connection.
+ # Exclusivity also implies that queue is automatically deleted when connection
+ # is closed. Only one consumer is allowed to remove messages from exclusive queue.
#
- # If the queue has been previously declared, this option is ignored
- # on subsequent declarations.
+ # @option opts [Boolean] :nowait (true) If set, the server will not respond to the method. The client should
+ # not wait for a reply method. If the server could not complete the
+ # method it will raise a channel or connection exception.
#
- # Any remaining messages in the queue will be purged when the queue
- # is deleted regardless of the message's persistence setting.
#
- # * :nowait => true | false (default true)
- # If set, the server will not respond to the method. The client should
- # not wait for a reply method. If the server could not complete the
- # method it will raise a channel or connection exception.
+ # @raise [AMQP::Error] Raised when queue is redeclared with parameters different from original declaration.
+ # @raise [AMQP::Error] Raised when queue is declared with :passive => true and the queue does not exist.
+ # @raise [AMQP::Error] Raised when queue is declared with :exclusive => true and queue with that name already exist.
#
- def queue(name, opts = {}, &block)
- raise ArgumentError, "queue name must not be nil. Use '' (empty string) for server-named queues." if name.nil?
-
- if name && !name.empty? && (queue = self.queues.find { |queue| queue.name == name })
+ #
+ # @yield [queue, declare_ok] Yields successfully declared queue instance and AMQP method (queue.declare-ok) instance. The latter is optional.
+ # @yieldparam [Queue] queue Queue that is successfully declared and is ready to be used.
+ # @yieldparam [AMQP::Protocol::Queue::DeclareOk] declare_ok AMQP queue.declare-ok) instance.
+ #
+ # @see Queue
+ # @see Queue#initialize
+ # @see http://bit.ly/hw2ELX AMQP 0.9.1 specification (Section 2.1.4)
+ #
+ # @return [Queue]
+ # @api public
+ def queue(name = AMQ::Protocol::EMPTY_STRING, opts = {}, &block)
+ if name && !name.empty? && (queue = find_queue(name))
extended_opts = Queue.add_default_options(name, opts, block)
validate_parameters_match!(queue, extended_opts)
queue
else
- q = Queue.new(self, name, opts, &block)
- self.queues << q
+ queue = if block.nil?
+ Queue.new(self, name, opts)
+ else
+ shim = Proc.new { |q, method|
+ queue = find_queue(method.queue)
+ if block.arity == 1
+ block.call(queue)
+ else
+ block.call(queue, method.consumer_count, method.message_count)
+ end
+ }
+ Queue.new(self, name, opts, &shim)
+ end
- q
+ register_queue(queue)
end
end
+ # Returns true if channel is not closed.
+ # @return [Boolean]
+ # @api public
+ def open?
+ self.status == :opened || self.status == :opening
+ end # open?
+
+
def queue!(name, opts = {}, &block)
- self.queues.add! Queue.new(self, name, opts, &block)
+ # TODO
+ raise NotImplementedError.new
end
- # Takes a channel, queue and optional object.
+
+ # Instantiates and returns an RPC instance associated with this channel.
#
# The optional object may be a class name, module name or object
# instance. When given a class or module name, the object is instantiated
# during this setup. The passed queue is automatically subscribed to so
# it passes all messages (and their arguments) to the object.
@@ -664,319 +642,113 @@
# which does all of the heavy lifting with the proxy. Some client
# elsewhere must call this method *with* the optional block so that
# there is a valid destination. Failure to do so will just enqueue
# marshalled messages that are never consumed.
#
- # EM.run do
- # server = AMQP::Channel.new.rpc('hash table node', Hash)
+ # @example Use of RPC
#
- # client = AMQP::Channel.new.rpc('hash table node')
- # client[:now] = Time.now
- # client[:one] = 1
+ # # TODO
#
- # client.values do |res|
- # p 'client', :values => res
- # end
#
- # client.keys do |res|
- # p 'client', :keys => res
- # EM.stop_event_loop
- # end
- # end
- #
+ # @param [String, Queue] Queue to be used by RPC server.
+ # @return [RPC]
+ # @api public
def rpc(name, obj = nil)
- rpcs[name] ||= RPC.new(self, name, obj)
+ RPC.new(self, name, obj)
end
- def close(&block)
- @on_close = block
- if @deferred_status == :succeeded
- send Protocol::Channel::Close.new(:reply_code => 200,
- :reply_text => 'bye',
- :method_id => 0,
- :class_id => 0)
- else
- @closing = true
- end
- end
- # Define a message and callback block to be executed on all
- # errors.
- def self.error msg = nil, &blk
- if blk
- @error_callback = blk
- else
- @error_callback.call(msg) if @error_callback and msg
- end
- end
-
- def prefetch(size)
- @prefetch_size = size
-
- send Protocol::Basic::Qos.new(:prefetch_size => 0, :prefetch_count => size, :global => false)
-
- self
- end
-
- # Asks the broker to redeliver all unacknowledged messages on this
- # channel.
+ # Define a callback to be run on channel-level exception.
#
- # * requeue (default false)
- # If this parameter is false, the message will be redelivered to the original recipient.
- # If this flag is true, the server will attempt to requeue the message, potentially then
- # delivering it to an alternative subscriber.
+ # @param [String] msg Error message
#
- def recover(requeue = false)
- send Protocol::Basic::Recover.new(:requeue => requeue)
- self
+ # @api public
+ def self.error(msg = nil, &block)
+ # TODO
+ raise NotImplementedError.new
end
- # Returns a hash of all the exchange proxy objects.
+ # @param [Fixnum] size
+ # @param [Boolean] global (false)
#
- # Not typically called by client code.
- def exchanges
- @exchanges ||= AMQP::Collection.new
- end
-
- # Returns a hash of all the queue proxy objects.
+ # @return [Channel] self
#
- # Not typically called by client code.
- def queues
- @queues ||= AMQP::Collection.new
- end
+ # @api public
+ def prefetch(size, global = false, &block)
+ # RabbitMQ as of 2.3.1 does not support prefetch_size.
+ self.qos(0, size, global, &block)
- def get_queue
- if block_given?
- @get_queue_mutex.synchronize {
- yield( @get_queue ||= [] )
- }
- end
+ self
end
+
+
# Returns a hash of all rpc proxy objects.
#
- # Not typically called by client code.
+ # Most of the time, this method is not
+ # called by application code.
+ # @api plugin
def rpcs
- @rcps ||= {}
+ @rpcs.values
end
- # Queue objects keyed on their consumer tags.
- #
- # Not typically called by client code.
- def consumers
- @consumers ||= {}
- end
- def reset
- @deferred_status = nil
- @channel = nil
- @queues_awaiting_declare_ok = Array.new
-
- initialize @connection
-
- @consumers = {}
-
- exs = @exchanges
- @exchanges = AMQP::Collection.new
- exs.each { |e| e.reset } if exs
-
- qus = @queues
- @queues = AMQP::Collection.new
- qus.each { |q| q.reset } if qus
-
- prefetch(@prefetch_size) if @prefetch_size
- end
-
-
#
# Implementation
#
- # May raise a AMQP::Channel::Error exception when the frame payload contains a
- # Protocol::Channel::Close object.
+
+ # Resets channel state (for example, list of registered queue objects and so on).
#
- # This usually occurs when a client attempts to perform an illegal
- # operation. A short, and incomplete, list of potential illegal operations
- # follows:
- # * publish a message to a deleted exchange (NOT_FOUND)
- # * declare an exchange using the reserved 'amq.' naming structure (ACCESS_REFUSED)
+ # Most of the time, this method is not
+ # called by application code.
#
- def process_frame(frame)
- log :received, frame
+ # @private
+ # @api plugin
+ def reset
+ # TODO
+ raise NotImplementedError.new
+ end
- case frame
- when Frame::Header
- @header = frame.payload
- @body = ''
- check_content_completion
+ # @private
+ # @api private
+ def self.channel_id_mutex
+ @channel_id_mutex ||= Mutex.new
+ end
- when Frame::Body
- @body << frame.payload
- check_content_completion
+ # @return [Fixnum]
+ # @private
+ # @api private
+ def self.next_channel_id
+ channel_id_mutex.synchronize do
+ @last_channel_id ||= 0
+ @last_channel_id += 1
- when Frame::Method
- handle_method(frame)
+ @last_channel_id
end
- end # process_frame
+ end
+ # @private
+ # @api plugin
+ def register_rpc(rpc)
+ raise ArgumentError, "argument is nil!" unless rpc
- def send(*args)
- conn.callback { |c|
- @_send_mutex.synchronize do
- args.each do |data|
- unless self.closed?
- data.ticket = @ticket if @ticket and data.respond_to? :ticket=
- log :sending, data
- c.send data, :channel => @channel
- else
- unless data.class == AMQP::Protocol::Channel::CloseOk
- raise ChannelClosedError.new(self)
- end
- end
- end
- end
- }
- end # send
+ @rpcs[rpc.name] = rpc
+ end # register_rpc(rpc)
+ # @private
+ # @api plugin
+ def find_rpc(name)
+ @rpcs[name]
+ end
- def check_content_completion
- if @body.length >= @header.size
- @header.properties.update(@method.arguments)
- @consumer.receive @header, @body if @consumer
- @body = @header = @consumer = @method = nil
- end
- end # check_content_completion
protected
- def handle_method(frame)
- case method = frame.payload
- when Protocol::Channel::OpenOk
- send Protocol::Access::Request.new(:realm => '/data',
- :read => true,
- :write => true,
- :active => true,
- :passive => true)
-
- when Protocol::Access::RequestOk
- @ticket = method.ticket
- callback {
- send Protocol::Channel::Close.new(:reply_code => 200,
- :reply_text => 'bye',
- :method_id => 0,
- :class_id => 0)
- } if @closing
- succeed
-
- when Protocol::Basic::CancelOk
- if @consumer = consumers[ method.consumer_tag ]
- @consumer.cancelled
- else
- AMQP::Channel.error "Basic.CancelOk for invalid consumer tag: #{method.consumer_tag}"
- end
-
- when Protocol::Exchange::DeclareOk
- # We can't use exchanges[method.exchange] because if the name would
- # be an empty string, then AMQP broker generated a random one.
- exchanges = self.exchanges.select { |exchange| exchange.opts[:nowait].eql?(false) }
- exchange = exchanges.reverse.find { |exchange| exchange.status.eql?(:unfinished) }
- exchange.receive_response method
-
- when Protocol::Queue::DeclareOk
- queue = @queues_awaiting_declare_ok.shift
-
- queue.receive_status method
- when Protocol::Queue::BindOk
- # We can't use queues[method.queue] because if the name would
- # be an empty string, then AMQP broker generated a random one.
- queues = self.queues.select { |queue| queue.sync_bind }
- queue = queues.reverse.find { |queue| queue.status.eql?(:unbound) }
- queue.after_bind method
-
- when Protocol::Basic::Deliver, Protocol::Basic::GetOk
- @method = method
- @header = nil
- @body = ''
-
- if method.is_a? Protocol::Basic::GetOk
- @consumer = get_queue { |q| q.shift }
- AMQP::Channel.error "No pending Basic.GetOk requests" unless @consumer
- else
- @consumer = consumers[ method.consumer_tag ]
- AMQP::Channel.error "Basic.Deliver for invalid consumer tag: #{method.consumer_tag}" unless @consumer
- end
-
- when Protocol::Basic::GetEmpty
- if @consumer = get_queue { |q| q.shift }
- @consumer.receive nil, nil
- else
- AMQP::Channel.error "Basic.GetEmpty for invalid consumer"
- end
-
- when Protocol::Channel::Close
- @status = :closed
- AMQP::Channel.error "#{method.reply_text} in #{Protocol.classes[method.class_id].methods[method.method_id]} on #{@channel}"
-
- when Protocol::Channel::CloseOk
- @status = :closed
- @on_close && @on_close.call(self)
-
- @closing = false
- conn.callback { |c|
- c.channels.delete @channel
- c.close if c.channels.empty?
- }
-
- when Protocol::Basic::ConsumeOk
- if @consumer = consumers[ method.consumer_tag ]
- @consumer.confirm_subscribe
- else
- AMQP::Channel.error "Basic.ConsumeOk for invalid consumer tag: #{method.consumer_tag}"
- end
- when Protocol::Basic::Return
- @method = method
- end # case
- end # handle_method(frame)
-
-
-
- private
-
- def log(*args)
- return unless AMQP::logging
- pp args
- puts
- end # log
-
def validate_parameters_match!(entity, parameters)
unless entity.opts == parameters || parameters[:passive]
raise AMQP::IncompatibleOptionsError.new(entity.name, entity.opts, parameters)
end
end # validate_parameters_match!(entity, parameters)
end # Channel
end # AMQP
-
-
-MQ = AMQP::Channel
-
-#
-# Backwards compatibility with 0.6.x
-#
-
-class MQ
- # unique identifier
- def MQ.id
- Thread.current[:mq_id] ||= "#{`hostname`.strip}-#{Process.pid}-#{Thread.current.object_id}"
- end
-
- def MQ.default
- # TODO: clear this when connection is closed
- Thread.current[:mq] ||= MQ.new
- end
-
- # Allows for calls to all MQ instance methods. This implicitly calls
- # MQ.new so that a new channel is allocated for subsequent operations.
- def MQ.method_missing(meth, *args, &blk)
- MQ.default.__send__(meth, *args, &blk)
- end
-end