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NAME

AnyEvent::RabbitMQ::Channel - Abstraction of an AMQP channel.

SYNOPSIS

my $ch = $rf->open_channel();
$ch->declare_exchange(exchange => 'test_exchange');

DESCRIPTION

A RabbitMQ channel.

A channel is a light-weight virtual connection within a TCP connection to a RabbitMQ broker.

ARGUMENTS FOR open_channel

on_close

Callback invoked when the channel closes. Callback will be passed the incoming message that caused the close, if any.

on_return

Callback invoked when a mandatory or immediate message publish fails. Callback will be passed the incoming message, with accessors method_frame, header_frame, and body_frame.

METHODS

declare_exchange (%args)

Declare an exchange (to publish messages to) on the server.

Arguments:

on_success
on_failure
type

Default 'direct'

passive

Default 0

durable

Default 0

auto_delete

Default 0

internal

Default 0

exchange

The name of the exchange

bind_exchange

Binds an exchange to another exchange, with a routing key.

Arguments:

source

The name of the source exchange to bind

destination

The name of the destination exchange to bind

routing_key

The routing key to bind with

unbind_exchange

delete_exchange

declare_queue

Declare a queue (create it if it doesn't exist yet) for publishing messages to on the server.

my $done    = AnyEvent->condvar;
$channel->declare_queue(
   exchange    => $queue_exchange,
   queue       => $queueName,
   durable     => 0,
   auto_delete => 1,
   passive     => 0,
   arguments   => { 'x-expires' => 0, },
   on_success  => sub { $done->send; },
   on_failure  => sub {
       say "Unable to create queue $queueName";
       $done->send;
   },
);
$done->recv;

Arguments:

queue

Name of the queue to be declared. If the queue name is the empty string, RabbitMQ will create a unique name for the queue. This is useful for temporary/private reply queues.

on_success

Callback that is called when the queue was declared successfully. The argument to the callback is of type Net::AMQP::Frame::Method. To get the name of the Queue (if you declared it with an empty name), you can say

on_success => sub {
    my $method = shift;
    my $name   = $method->method_frame->queue;
};
on_failure

Callback that is called when the declaration of the queue has failed.

auto_delete

0 or 1, default 0

passive

0 or 1, default 0

durable

0 or 1, default 0

exclusive

0 or 1, default 0

no_ack

0 or 1, default 1

ticket

default 0

arguments

arguments is a hashref of additional parameters which RabbitMQ extensions may use. This list is not complete and your RabbitMQ server configuration will determine which arguments are valid and how they act.

x-expires

The queue will automatically be removed after being idle for this many milliseconds.

Default of 0 disables automatic queue removal.

bind_queue

Binds a queue to an exchange, with a routing key.

Arguments:

queue

The name of the queue to bind

exchange

The name of the exchange to bind

routing_key

The routing key to bind with

unbind_queue

purge_queue

Flushes the contents of a queue.

delete_queue

Deletes a queue. The queue may not have any active consumers.

consume

Subscribe to consume messages from a queue.

Arguments:

queue

The name of the queue to be consumed from.

on_consume

Callback called with an argument of the message which has been consumed.

The message is a hash reference, where the value to key header is an object of type Net::AMQP::Protocol::Basic::ContentHeader, body is a Net::AMQP::Frame::Body, and deliver a Net::AMQP::Frame::Method.

on_cancel

Callback called if consumption is cancelled. This may be at client request or as a side effect of queue deletion. (Notification of queue deletion is a RabbitMQ extension.)

consumer_tag

Identifies this consumer, will be auto-generated if you do not provide it, but you must supply a value if you want to be able to later cancel the subscription.

on_success

Callback called if the subscription was successful (before the first message is consumed).

on_failure

Callback called if the subscription fails for any reason.

no_ack

Pass through the no_ack flag. Defaults to 1. If set to 1, the server will not expect messages to be acknowledged.

publish

Publish a message to an exchange.

Arguments:

exchange

The name of the exchange to send the message to.

routing_key

The routing key with which to publish the message.

Hash of AMQP message header info, including the confusingly similar element "headers", which may contain arbitrary string key/value pairs.

body

The text body of the message to send.

mandatory

Boolean; if true, then if the message doesn't land in a queue (e.g. the exchange has no bindings), it will be "returned." (see "on_return")

immediate

Boolean; if true, then if the message cannot be delivered directly to a consumer, it will be "returned." (see "on_return")

on_ack

Callback called with the frame that acknowledges receipt (if channel is in confirm mode), typically Net::AMQP::Protocol::Basic::Ack.

on_nack

Callback called with the frame that declines receipt (if the channel is in confirm mode), typically Net::AMQP::Protocol::Basic::Nack or Net::AMQP::Protocol::Channel::Close.

on_return

In AMQP, a "returned" message is one that cannot be delivered in compliance with the immediate or mandatory flags.

If in confirm mode, this callback will be called with the frame that reports message return, typically Net::AMQP::Protocol::Basic::Return. If confirm mode is off or this callback is not provided, then the channel or connection objects' on_return callbacks (if any), will be called instead.

NOTE: If confirm mode is on, the on_ack or on_nack callback will be called whether or not on_return is called first.

cancel

Cancel a queue subscription.

Note that the cancellation will not take place at once, and further messages may be consumed before the subscription is cancelled. No further messages will be consumed after the on_success callback has been called.

Arguments:

consumer_tag

Identifies this consumer, needs to be the value supplied when the queue is initially consumed from.

on_success

Callback called if the subscription was successfully cancelled.

on_failure

Callback called if the subscription could not be cancelled for any reason.

get

Try to get a single message from a queue.

Arguments:

queue

Mandatory. Name of the queue to try to receive a message from.

on_success

Will be called either with either a message, or, if the queue is empty, a notification that there was nothing to collect from the queue.

on_failure

This callback will be called if an error is signalled on this channel.

no_ack

0 or 1, default 1

ack

qos

confirm

Put channel into confirm mode. In confirm mode, publishes are confirmed by the server, so the on_ack callback of publish works.

recover

select_tx

commit_tx

rollback_tx

AUTHOR, COPYRIGHT AND LICENSE

See AnyEvent::RabbitMQ for author(s), copyright and license.