11.4. Link Properties

reliability

one of: unreliable, at-least-once, at-most-once ^[a], exactly-once ^[b]

Currently only unreliable and at-least-once are supported. See the footnotes for further details.

Reliability indicates the level of link reliability requested by the sender or receiver. unreliable and at-most-once are currently treated as synonyms, and allow messages to be lost if a broker crashes or the connection to a broker is lost. at-least-once guarantees that a message is not lost, but duplicates may be received. exactly-once guarantees that a message is not lost, and is delivered precisely once.

durable

One of: True, False.

Indicates whether the link survives a loss of volatile storage e.g. if the broker is restarted.

x-declare

A nested map whose values correspond to the valid fields of an AMQP 0-10 queue-declare command.

These values can be used to customize the subscription queue in the case of receiving from an exchange. Note however that they are protocol specific.

x-subscribe

A nested map whose values correspond to the valid fields of an AMQP 0-10 message-subscribe command.

These values can be used to customize the subscription.

x-bindings

A nested list each of whose entries is a map that may contain fields (queue, exchange, key and arguments) describing an AMQP 0-10 binding.

These bindings are established during resolution independent of the create option. They are considered logically part of the linking process rather than of node creation.

filter

A map containing name, descriptor, and value, describing an AMQP 1.0 filter.

name