AMQP 0.9.1 protocol binding

Edit this page

You use the AMQP 0.9.1 binding to connect Ditto with message brokers like RabbitMQ for consuming and publishing messages.

TL;DR: Configure an AMQP 0.9.1 connection with connectionType: "amqp-091". Source addresses are queue names, and target addresses use the format exchange_name/routing_key.

Overview

The AMQP 0.9.1 protocol binding lets you consume messages from AMQP 0.9.1 brokers via sources and publish messages via targets.

When you send messages in Ditto Protocol format (UTF-8 encoded strings), set the content-type to:

application/vnd.eclipse.ditto+json

For other payload formats, configure a payload mapping.

AMQP 0.9.1 properties

Ditto interprets these AMQP 0.9.1 properties:

content-type – defines the Ditto Protocol content type
correlation-id – correlates request messages to responses

Connection URI format

amqp://user:password@hostname:5672/vhost

Use amqps:// for TLS-secured connections.

Source configuration

The common source configuration applies. Source addresses are AMQP 0.9.1 queue names:

{
  "addresses": ["queueName"],
  "authorizationContext": ["ditto:inbound-auth-subject"]
}

Source acknowledgement handling

When you configure acknowledgement requests:

Successful acknowledgements – Ditto sends an Ack for the received deliveryTag
Failed with redelivery needed – Ditto sends a Nack with requeue: true
Failed without redelivery – Ditto sends a Nack with requeue: false

Target configuration

The common target configuration applies. The target address combines the exchange name and routing key:

{
  "address": "exchangeName/routingKey",
  "topics": [
    "_/_/things/twin/events",
    "_/_/things/live/messages"
  ],
  "authorizationContext": ["ditto:outbound-auth-subject"]
}

The target address supports placeholders.

Target acknowledgement handling

When you configure issued acknowledgement labels:

Status	Condition
`200`	Message successfully ACKed by the broker
`400`	Broker does not support publisher confirms
`503`	Broker negatively confirmed the message

Specific configuration options

There are no AMQP 0.9.1-specific configuration properties.

Example connection JSON

{
  "id": "rabbit-example-connection-123",
  "connectionType": "amqp-091",
  "connectionStatus": "open",
  "failoverEnabled": true,
  "uri": "amqp://user:password@localhost:5672/vhost",
  "sources": [{
    "addresses": ["queueName"],
    "authorizationContext": ["ditto:inbound-auth-subject"]
  }],
  "targets": [{
    "address": "exchangeName/routingKey",
    "topics": [
      "_/_/things/twin/events",
      "_/_/things/live/messages"
    ],
    "authorizationContext": ["ditto:outbound-auth-subject"]
  }]
}