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AMQP 0-9-1 Operation Binding v0.3.0 ​

The AMQP operation binding provides detailed control over message routing and delivery behavior in AMQP 0-9-1. It allows you to configure properties such as message expiration, priority, delivery mode, and routing destinations.

Overview ​

This binding allows you to define AMQP-specific properties for publish and subscribe operations. These properties give you fine-grained control over how messages are handled by the broker.

Operation Properties ​

PropertyTypeDescription
expirationintegerTTL (Time-To-Live) for the message in milliseconds. It MUST be greater than or equal to zero.
userIdstringIdentifies the user who has sent the message.
cc[string]The routing keys the message should be routed to at the time of publishing.
priorityintegerA priority for the message. Higher numbers indicate higher priority.
deliveryModeintegerDelivery mode of the message. 1 for transient, 2 for persistent.
mandatorybooleanIf true, the message is returned to the publisher if it cannot be routed to any queue.
bcc[string]Like cc but the routing keys are not passed to the consumer.
timestampbooleanIf true, the message MUST include a timestamp property.
ackbooleanIf true, the consumer should acknowledge the message.
bindingVersionstringThe version of this binding. For v0.3.0, this MUST be 0.3.0.

Examples ​

Persistent, High-Priority Message ​

This example shows a message that is durable, has a high priority, and must be routed.

yaml
operations:
  highPriorityTask:
    bindings:
      amqp:
        deliveryMode: 2 # Persistent
        priority: 10
        mandatory: true
        timestamp: true
        ack: true
        bindingVersion: '0.3.0'

Message with Expiration and CC Routing ​

This example defines a transient message that expires after 60 seconds and is routed to specific logging and analytics queues via the cc property.

yaml
operations:
  userSignup:
    bindings:
      amqp:
        expiration: 60000 # 1 minute
        deliveryMode: 1 # Transient
        cc:
          - user.logs
          - user.analytics
        userId: 'system'
        ack: true
        bindingVersion: '0.3.0'

Blind Carbon Copy (BCC) for Auditing ​

This example uses bcc to route a copy of the message to an audit trail without the consumer's knowledge.

yaml
operations:
  processPayment:
    bindings:
      amqp:
        deliveryMode: 2 # Persistent
        bcc:
          - external.audit.trail
        mandatory: true
        ack: true
        bindingVersion: '0.3.0'

Use Cases ​

Task Queues with Priority ​

Set the priority property to ensure high-priority tasks (e.g., password resets) are processed before lower-priority ones (e.g., batch processing).

Reliable Messaging ​

For critical messages, set deliveryMode to 2 (persistent), mandatory to true, and require consumer acknowledgments with ack: true to ensure guaranteed delivery.

Event Auditing ​

Use the bcc field to silently send copies of events to a separate, secure queue or exchange for auditing and compliance purposes, without altering the primary message flow.

Temporary Notifications ​

Use the expiration property for time-sensitive notifications that should be discarded if not consumed quickly, preventing stale data from being processed.

Versioning ​

This binding is for version 0.3.0 of the AMQP binding specification.