Class: Qpid::Proton::Messenger

Inherits:
Object
  • Object
show all
Includes:
ExceptionHandling
Defined in:
lib/qpid_proton/messenger.rb

Overview

The Messenger class defines a high level interface for sending and receiving Messages. Every Messenger contains a single logical queue of incoming messages and a single logical queue of outgoing messages. These messages in these queues may be destined for, or originate from, a variety of addresses.

The messenger interface is single-threaded. All methods except one ( #interrupt ) are intended to be used from within the messenger thread.

Sending & Receiving Messages

The Messenger class works in conjuction with the Message class. The Message class is a mutable holder of message content.

The put method copies its Message to the outgoing queue, and may send queued messages if it can do so without blocking. The send method blocks until it has sent the requested number of messages, or until a timeout interrupts the attempt.

Similarly, the recv method receives messages into the incoming queue, and may block as it attempts to receive the requested number of messages, or until timeout is reached. It may receive fewer than the requested number. The get method pops the eldest Message off the incoming queue and copies it into the Message object that you supply. It will not block.

The blocking attribute allows you to turn off blocking behavior entirely, in which case send and recv will do whatever they can without blocking, and then return. You can then look at the number of incoming and outgoing messages to see how much outstanding work still remains.

Class Method Summary collapse

Instance Method Summary collapse

Methods included from ExceptionHandling

#check_for_error

Constructor Details

#initialize(name = nil) ⇒ Messenger

Creates a new Messenger.

The name parameter is optional. If one is not provided then a unique name is generated.

Options

  • name - the name (def. nil)



71
72
73
74
75
 
# File 'lib/qpid_proton/messenger.rb', line 71

def initialize(name = nil)
  @impl = Cproton.pn_messenger(name)
  @selectables = {}
  ObjectSpace.define_finalizer(self, self.class.finalize!(@impl))
end

Class Method Details

.finalize!(impl) ⇒ Object

:nodoc:



77
78
79
80
81
 
# File 'lib/qpid_proton/messenger.rb', line 77

def self.finalize!(impl) # :nodoc:
  proc {
    Cproton.pn_messenger_free(impl)
  }
end

Instance Method Details

#accept(tracker = nil) ⇒ Object

Signal the sender that you have acted on the Message pointed to by the tracker. If no tracker is supplied, then all messages that have been returned by the get method are accepted, except those that have already been auto-settled by passing beyond your incoming window size.

Options

  • tracker - the tracker

Raises:

  • (TypeError) 


528
529
530
531
532
533
534
535
536
537
 
# File 'lib/qpid_proton/messenger.rb', line 528

def accept(tracker = nil)
  raise TypeError.new("invalid tracker: #{tracker}") unless tracker.nil? or valid_tracker?(tracker)
  if tracker.nil? then
    tracker = self.incoming_tracker
    flag = Cproton::PN_CUMULATIVE
  else
    flag = 0
  end
  check_for_error(Cproton.pn_messenger_accept(@impl, tracker.impl, flag))
end

#blocking=(blocking) ⇒ Object

Sets the blocking mode.



136
137
138
 
# File 'lib/qpid_proton/messenger.rb', line 136

def blocking=(blocking)
  Cproton.pn_messenger_set_blocking(@impl, blocking)
end

#blocking? ⇒ Boolean

Returns true if blocking mode is enabled.

Enable or disable blocking behavior during message sending and receiving. This affects every blocking call, with the exception of work(). Currently, the affected calls are send, recv, and stop.

Returns:

  • (Boolean) 


131
132
133
 
# File 'lib/qpid_proton/messenger.rb', line 131

def blocking?
  Cproton.pn_messenger_is_blocking(@impl)
end

#certificate ⇒ Object

Returns the path to a certificate file.



239
240
241
 
# File 'lib/qpid_proton/messenger.rb', line 239

def certificate
  Cproton.pn_messenger_get_certificate(@impl)
end

#certificate=(certificate) ⇒ Object

Path to a certificate file for the Messenger.

This certificate is used when the Messenger accepts or establishes SSL/TLS connections. This property must be specified for the Messenger to accept incoming SSL/TLS connections and to establish client authenticated outgoing SSL/TLS connection. Non client authenticated outgoing SSL/TLS connections do not require this property.

Options

  • certificate - the certificate



233
234
235
 
# File 'lib/qpid_proton/messenger.rb', line 233

def certificate=(certificate)
  Cproton.pn_messenger_set_certificate(@impl, certificate)
end

#deadline ⇒ Object 



159
160
161
162
 
# File 'lib/qpid_proton/messenger.rb', line 159

def deadline
  tstamp = Cproton.pn_messenger_deadline(@impl)
  return tstamp / 1000.0 unless tstamp.nil?
end

#errno ⇒ Object

Returns the most recent error number.



172
173
174
 
# File 'lib/qpid_proton/messenger.rb', line 172

def errno
  Cproton.pn_messenger_errno(@impl)
end

#error ⇒ Object

Returns the most recent error message.



178
179
180
 
# File 'lib/qpid_proton/messenger.rb', line 178

def error
  Cproton.pn_error_text(Cproton.pn_messenger_error(@impl))
end

#error? ⇒ Boolean

Reports whether an error occurred.

Returns:

  • (Boolean) 


166
167
168
 
# File 'lib/qpid_proton/messenger.rb', line 166

def error?
  !Cproton.pn_messenger_errno(@impl).zero?
end

#get(msg = nil) ⇒ Object

Moves the message from the head of the incoming message queue into the supplied message object. Any content in the supplied message will be overwritten. A tracker for the incoming Message is returned. The tracker can later be used to communicate your acceptance or rejection of the Message.

If no message is provided in the argument, then one is created. In either case, the one returned will be the fetched message.

Options

  • msg - the (optional) Message instance to be used



329
330
331
332
333
334
335
336
337
338
339
 
# File 'lib/qpid_proton/messenger.rb', line 329

def get(msg = nil)
  msg_impl = nil
  if msg.nil? then
    msg_impl = nil
  else
    msg_impl = msg.impl
  end
  check_for_error(Cproton.pn_messenger_get(@impl, msg_impl))
  msg.post_decode unless msg.nil?
  return incoming_tracker
end

#incoming ⇒ Object

Returns the number of messages in the incoming queue that have not been retrieved.



401
402
403
 
# File 'lib/qpid_proton/messenger.rb', line 401

def incoming
  Cproton.pn_messenger_incoming(@impl)
end

#incoming_tracker ⇒ Object

Returns a Tracker for the most recently received message.



512
513
514
515
516
 
# File 'lib/qpid_proton/messenger.rb', line 512

def incoming_tracker
  impl = Cproton.pn_messenger_incoming_tracker(@impl)
  return nil if impl == -1
  Qpid::Proton::Tracker.new(impl)
end

#incoming_window ⇒ Object

Returns the incoming window.



617
618
619
 
# File 'lib/qpid_proton/messenger.rb', line 617

def incoming_window
  Cproton.pn_messenger_get_incoming_window(@impl)
end

#incoming_window=(window) ⇒ Object

Sets the incoming window.

The Messenger will track the remote status of this many incoming deliveries after they have been accepted or rejected.

Messages enter this window only when you take them into your application using get(). If your incoming window size is n, and you get n+1 messages without explicitly accepting or rejecting the oldest message, then the message that passes beyond the edge of the incoming window will be assigned the default disposition of its link.

Options

  • window - the window size

Raises:

  • (TypeError) 


610
611
612
613
 
# File 'lib/qpid_proton/messenger.rb', line 610

def incoming_window=(window)
  raise TypeError.new("invalid window: #{window}") unless valid_window?(window)
  check_for_error(Cproton.pn_messenger_set_incoming_window(@impl, window))
end

#interrupt ⇒ Object

Attempts interrupting of the messenger thread.

The Messenger interface is single-threaded, and this is the only function intended to be called from outside of is thread.

Call this from a non-Messenger thread to interrupt it while it is blocking. This will cause a ::InterruptError to be raised.

If there is no currently blocking call, then the next blocking call will be affected, even if it is within the same thread that originated the interrupt.



371
372
373
 
# File 'lib/qpid_proton/messenger.rb', line 371

def interrupt
  check_for_error(Cproton.pn_messenger_interrupt(@impl))
end

#name ⇒ Object

Returns the name.



85
86
87
 
# File 'lib/qpid_proton/messenger.rb', line 85

def name
  Cproton.pn_messenger_name(@impl)
end

#outgoing ⇒ Object

Returns the number messages in the outgoing queue that have not been transmitted.



394
395
396
 
# File 'lib/qpid_proton/messenger.rb', line 394

def outgoing
  Cproton.pn_messenger_outgoing(@impl)
end

#outgoing_tracker ⇒ Object

Returns a Tracker for the message most recently sent via the put method.



504
505
506
507
508
 
# File 'lib/qpid_proton/messenger.rb', line 504

def outgoing_tracker
  impl = Cproton.pn_messenger_outgoing_tracker(@impl)
  return nil if impl == -1
  Qpid::Proton::Tracker.new(impl)
end

#outgoing_window ⇒ Object

Returns the outgoing window.



641
642
643
 
# File 'lib/qpid_proton/messenger.rb', line 641

def outgoing_window
  Cproton.pn_messenger_get_outgoing_window(@impl)
end

#outgoing_window=(window) ⇒ Object

Sets the outgoing window.

The Messenger will track the remote status of this many outgoing deliveries after calling send. A Message enters this window when you call the put() method with the message. If your outgoing window size is n, and you call put n+1 times, status information will no longer be available for the first message.

Options

  • window - the window size

Raises:

  • (TypeError) 


634
635
636
637
 
# File 'lib/qpid_proton/messenger.rb', line 634

def outgoing_window=(window)
  raise TypeError.new("invalid window: #{window}") unless valid_window?(window)
  check_for_error(Cproton.pn_messenger_set_outgoing_window(@impl, window))
end

#passive=(mode) ⇒ Object

Turns passive mode on or off.

When set to passive mode, Messenger will not attempt to perform I/O operations internally. In this mode it is necesssary to use the Selectable type to drive any I/O needed to perform requestioned actions.

In this mode Messenger will never block.



155
156
157
 
# File 'lib/qpid_proton/messenger.rb', line 155

def passive=(mode)
  Cproton.pn_messenger_set_passive(@impl, mode)
end

#passive? ⇒ Boolean

Returns true if passive mode is enabled.

Returns:

  • (Boolean) 


142
143
144
 
# File 'lib/qpid_proton/messenger.rb', line 142

def passive?
  Cproton.pn_messenger_is_passive(@impl)
end

#password ⇒ Object

Returns the password property for the Messenger.private_key file.



102
103
104
 
# File 'lib/qpid_proton/messenger.rb', line 102

def password
  Cproton.pn_messenger_get_password(@impl)
end

#password=(password) ⇒ Object

This property contains the password for the Messenger.private_key file, or nil if the file is not encrypted.

Arguments

  • password - the password



96
97
98
 
# File 'lib/qpid_proton/messenger.rb', line 96

def password=(password)
  check_for_error(Cproton.pn_messenger_set_password(@impl, password))
end

#private_key ⇒ Object

Returns the path to a private key file.



260
261
262
 
# File 'lib/qpid_proton/messenger.rb', line 260

def private_key
  Cproton.pn_messenger_get_private_key(@impl)
end

#private_key=(key) ⇒ Object

Path to a private key file for the Messenger.

The property must be specified for the Messenger to accept incoming SSL/TLS connections and to establish client authenticated outgoing SSL/TLS connections. Non client authenticated SSL/TLS connections do not require this property.

Options

  • key - the key file



254
255
256
 
# File 'lib/qpid_proton/messenger.rb', line 254

def private_key=(key)
  Cproton.pn_messenger_set_private_key(@impl, key)
end

#put(message) ⇒ Object

Places the content contained in the message onto the outgoing queue of the Messenger.

This method will never block, however it will send any unblocked Messages in the outgoing queue immediately and leave any blocked Messages remaining in the outgoing queue. The send call may then be used to block until the outgoing queue is empty. The outgoing attribute may be used to check the depth of the outgoing queue.

Options

  • message - the message

Raises:

  • (TypeError) 


296
297
298
299
300
301
302
303
 
# File 'lib/qpid_proton/messenger.rb', line 296

def put(message)
  raise TypeError.new("invalid message: #{message}") if message.nil?
  raise ArgumentError.new("invalid message type: #{message.class}") unless message.kind_of?(Message)
  # encode the message first
  message.pre_encode
  check_for_error(Cproton.pn_messenger_put(@impl, message.impl))
  return outgoing_tracker
end

#receive(limit = -1)) ⇒ Object

Receives up to limit messages into the incoming queue. If no value for limit is supplied, this call will receive as many messages as it can buffer internally. If the Messenger is in blocking mode, this call will block until at least one Message is available in the incoming queue.

Options ====

  • limit - the maximum number of messages to receive



351
352
353
 
# File 'lib/qpid_proton/messenger.rb', line 351

def receive(limit = -1)
  check_for_error(Cproton.pn_messenger_recv(@impl, limit))
end

#receiving ⇒ Object 



355
356
357
 
# File 'lib/qpid_proton/messenger.rb', line 355

def receiving
  Cproton.pn_messenger_receiving(@impl)
end

#reject(tracker) ⇒ Object

Rejects the incoming message identified by the tracker. If no tracker is supplied, all messages that have been returned by the get method are rejected, except those that have already been auto-settled by passing beyond your outgoing window size.

Options

  • tracker - the tracker

Raises:

  • (TypeError) 


548
549
550
551
552
553
554
555
556
557
 
# File 'lib/qpid_proton/messenger.rb', line 548

def reject(tracker)
  raise TypeError.new("invalid tracker: #{tracker}") unless tracker.nil? or valid_tracker?(tracker)
  if tracker.nil? then
    tracker = self.incoming_tracker
    flag = Cproton::PN_CUMULATIVE
  else
    flag = 0
  end
  check_for_error(Cproton.pn_messenger_reject(@impl, tracker.impl, flag))
end

#rewrite(pattern, address) ⇒ Object

Similar to #route, except that the destination of the Message is determined before the message address is rewritten.

The outgoing address is only rewritten after routing has been finalized. If a message has an outgoing address of “amqp://0.0.0.0:5678”, and a rewriting rule that changes its outgoing address to “foo”, it will still arrive at the peer that is listening on “amqp://0.0.0.0:5678”, but when it arrives there, the receiver will see its outgoing address as “foo”.

The default rewrite rule removes username and password from addresses before they are transmitted.

Arguments

  • pattern - the outgoing address

  • address - the target address



481
482
483
 
# File 'lib/qpid_proton/messenger.rb', line 481

def rewrite(pattern, address)
  check_for_error(Cproton.pn_messenger_rewrite(@impl, pattern, address))
end

#route(pattern, address) ⇒ Object

Adds a routing rule to the Messenger’s internal routing table.

The route procedure may be used to influence how a Messenger will internally treat a given address or class of addresses. Every call to the route procedure will result in Messenger appending a routing rule to its internal routing table.

Whenever a Message is presented to a Messenger for delivery, it will match the address of this message against the set of routing rules in order. The first rule to match will be triggered, and instead of routing based on the address presented in the message, the Messenger will route based on the address supplied in the rule.

The pattern matching syntax supports two types of matches, a ‘%’ will match any character except a ‘/’, and a ‘*’ will match any character including a ‘/’.

A routing address is specified as a normal AMQP address, however it may additionally use substitution variables from the pattern match that triggered the rule.

Arguments

  • pattern - the address pattern

  • address - the target address

Examples

# route messages sent to foo to the destionaty amqp://foo.com
messenger.route("foo", "amqp://foo.com")

# any message to foobar will be routed to amqp://foo.com/bar
messenger.route("foobar", "amqp://foo.com/bar")

# any message to bar/<path> will be routed to the same path within
# the amqp://bar.com domain
messenger.route("bar/*", "amqp://bar.com/$1")

# route all Message objects over TLS
messenger.route("amqp:*", "amqps:$1")

# supply credentials for foo
messenger.route("amqp://foo.com/*", "amqp://user:[email protected]/$1")

# supply credentials for all domains
messenger.route("amqp://*", "amqp://user:password@$1")

# route all addresses through a single proxy while preserving the
# original destination
messenger.route("amqp://%$/*", "amqp://user:password@proxy/$1/$2")

# route any address through a single broker
messenger.route("*", "amqp://user:password@broker/$1")



459
460
461
 
# File 'lib/qpid_proton/messenger.rb', line 459

def route(pattern, address)
  check_for_error(Cproton.pn_messenger_route(@impl, pattern, address))
end

#selectable ⇒ Object 



485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
 
# File 'lib/qpid_proton/messenger.rb', line 485

def selectable
  impl = Cproton.pn_messenger_selectable(@impl)

  # if we don't have any selectables, then return
  return nil if impl.nil?

  fd = Cproton.pn_selectable_fd(impl)

  selectable = @selectables[fd]
  if selectable.nil?
    selectable = Selectable.new(self, impl)
    @selectables[fd] = selectable
  end
  return selectable
end

#send(n = -1)) ⇒ Object

This call will block until the indicated number of messages have been sent, or until the operation times out. If n is -1 this call will block until all outgoing messages have been sent. If n is 0 then this call will send whatever it can without blocking.



311
312
313
 
# File 'lib/qpid_proton/messenger.rb', line 311

def send(n = -1)
  check_for_error(Cproton.pn_messenger_send(@impl, n))
end

#settle(tracker) ⇒ Object

Frees a Messenger from tracking the status associated with a given tracker. If you don’t supply a tracker, all outgoing messages up to the most recent will be settled.

Options

  • tracker - the tracker

Examples

Raises:

  • (TypeError) 


584
585
586
587
588
589
590
591
592
593
 
# File 'lib/qpid_proton/messenger.rb', line 584

def settle(tracker)
  raise TypeError.new("invalid tracker: #{tracker}") unless valid_tracker?(tracker)
  if tracker.nil? then
    tracker = self.incoming_tracker
    flag = Cproton::PN_CUMULATIVE
  else
    flag = 0
  end
  Cproton.pn_messenger_settle(@impl, tracker.impl, flag)
end

#start ⇒ Object

Currently a no-op placeholder. For future compatibility, do not send or recv messages before starting the Messenger.



186
187
188
 
# File 'lib/qpid_proton/messenger.rb', line 186

def start
  check_for_error(Cproton.pn_messenger_start(@impl))
end

#status(tracker) ⇒ Object

Gets the last known remote state of the delivery associated with the given tracker, as long as the Message is still within your outgoing window. (Also works on incoming messages that are still within your incoming queue. See TrackerStatus for details on the values returned.

Options

  • tracker - the tracker

Raises:

  • (TypeError) 


569
570
571
572
 
# File 'lib/qpid_proton/messenger.rb', line 569

def status(tracker)
  raise TypeError.new("invalid tracker: #{tracker}") unless valid_tracker?(tracker)
  Qpid::Proton::TrackerStatus.by_value(Cproton.pn_messenger_status(@impl, tracker.impl))
end

#stop ⇒ Object

Stops the Messenger, preventing it from sending or receiving any more messages.



193
194
195
 
# File 'lib/qpid_proton/messenger.rb', line 193

def stop
  check_for_error(Cproton.pn_messenger_stop(@impl))
end

#stopped ⇒ Object

Returns true iff a Messenger is in the stopped state. This function does not block.



200
201
202
 
# File 'lib/qpid_proton/messenger.rb', line 200

def stopped
  Cproton.pn_messenger_stopped(@impl)
end

#subscribe(address) ⇒ Object

Subscribes the Messenger to messages originating from the specified source. The source is an address as specified in the Messenger introduction with the following addition. If the domain portion of the address begins with the ‘~’ character, the Messenger will interpret the domain as host/port, bind to it, and listen for incoming messages. For example “~0.0.0.0”, “amqp://~0.0.0.0” will all bind to any local interface and listen for incoming messages. Ad address of # “amqps://~0.0.0.0” will only permit incoming SSL connections.

Raises:

  • (TypeError) 


214
215
216
217
218
219
 
# File 'lib/qpid_proton/messenger.rb', line 214

def subscribe(address)
  raise TypeError.new("invalid address: #{address}") if address.nil?
  subscription = Cproton.pn_messenger_subscribe(@impl, address)
  raise Qpid::Proton::ProtonError.new("Subscribe failed") if subscription.nil?
  Qpid::Proton::Subscription.new(subscription)
end

#timeout ⇒ Object

Returns the timeout period



121
122
123
 
# File 'lib/qpid_proton/messenger.rb', line 121

def timeout
  Cproton.pn_messenger_get_timeout(@impl)
end

#timeout=(timeout) ⇒ Object

Sets the timeout period, in milliseconds.

A negative timeout period implies an infinite timeout.

Options

  • timeout - the timeout period

Raises:

  • (TypeError) 


114
115
116
117
 
# File 'lib/qpid_proton/messenger.rb', line 114

def timeout=(timeout)
  raise TypeError.new("invalid timeout: #{timeout}") if timeout.nil?
  Cproton.pn_messenger_set_timeout(@impl, timeout)
end

#trusted_certificates ⇒ Object

The path to the databse of trusted certificates.



278
279
280
 
# File 'lib/qpid_proton/messenger.rb', line 278

def trusted_certificates
  Cproton.pn_messenger_get_trusted_certificates(@impl)
end

#trusted_certificates=(certificates) ⇒ Object

A path to a database of trusted certificates for use in verifying the peer on an SSL/TLS connection. If this property is nil, then the peer will not be verified.

Options

  • certificates - the certificates path



272
273
274
 
# File 'lib/qpid_proton/messenger.rb', line 272

def trusted_certificates=(certificates)
  Cproton.pn_messenger_set_trusted_certificates(@impl,certificates)
end

#unregister_selectable(fileno) ⇒ Object

Unregisters a selectable object.



646
647
648
 
# File 'lib/qpid_proton/messenger.rb', line 646

def unregister_selectable(fileno) # :nodoc:
  @selectables.delete(fileno)
end

#work(timeout = -1)) ⇒ Object

Sends or receives any outstanding messages queued for a Messenger.

This will block for the indicated timeout. This method may also do I/O other than sending and receiving messages. For example, closing connections after stop() has been called.



381
382
383
384
385
386
387
388
389
 
# File 'lib/qpid_proton/messenger.rb', line 381

def work(timeout=-1)
  err = Cproton.pn_messenger_work(@impl, timeout)
  if (err == Cproton::PN_TIMEOUT) then
    return false
  else
    check_for_error(err)
    return true
  end
end