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RabbitMQ Publish to Exchange#

This task publishes a message to a specified RabbitMQ exchange with a given routing key. It allows you to send data to different parts of your RabbitMQ infrastructure based on your configured exchanges and bindings.

Publish to Exchange Task

Inputs#

Name Data Type Description
Exchange Name String The name of the RabbitMQ exchange to publish the message to.
Exchange Type String The type of the exchange (e.g., direct, topic, fanout, headers). See Settings for details.
Key String The routing key to use when publishing the message.
Message String The message content to be published to the exchange.
Wait For Confirmation? Boolean If true, the task will wait for confirmation from RabbitMQ that the message has been received. Defaults to true.
Activate any Triggers the task to publish the message to the exchange.

Outputs#

Name Data Type Description
Success Boolean Emits true when the message is successfully published (and optionally confirmed).
Error Error Emits an Error object if publishing the message fails.

Settings#

On the General Tab, you have the usual settings and the following settings:

Name Data Type Default Description
Exchange Name String defaultExchange The identifier of RabbitMQ connection to use.
Exchange Type Enum fanout The type of the RabbitMQ exchange. Available options are: direct, topic, fanout, and custom.
Custom Exchange Type String If Exchange Type is set to custom, you must specify the custom exchange type here.
Key String defaultKey The topic key to publish to.
Message String The message to be sent.
Wait For Confirmation? Boolean false Should the system wait for confirmation.

Behavior#

The RabbitMQ Publish to Exchange task sends a message to a RabbitMQ Exchange for a particular topic. It also supports sending a message and expecting a confirmation from the RabbitMQ when Wait For Confirmation? is set to true.

When the Activate input is triggered, this task retrieves the configured exchange name, exchange type (potentially using the custom type if specified), routing key, and message from its input properties.

The Wait For Confirmation? setting determines whether the task waits for an acknowledgement from the RabbitMQ broker before emitting the Success output.

If the message is published successfully (and confirmed if Wait For Confirmation is true), the Success output emits true. If any error occurs during the publishing process (e.g., connection issues with RabbitMQ, invalid exchange name, routing errors), the error output will emit an Error object containing details about the failure.

Remarks#

  • This task is fundamental for sending messages within a RabbitMQ-based system. By configuring the exchange name, type, and routing key, you can precisely control where your messages are delivered.

  • Understanding the different RabbitMQ exchange types (direct, topic, fanout, headers) is crucial for correctly configuring this task.

    • Direct: Messages are routed to the queue(s) whose binding key exactly matches the routing key of the message.
    • Topic: Messages are routed to the queue(s) whose binding key matches a pattern. The routing key and binding key can contain wildcards (* for a single word, # for zero or more words).
    • Fanout: Messages are routed to all queues that are bound to the exchange, regardless of the routing key.
    • Headers: Messages are routed based on the headers attributes in the message. This type is less common and not directly exposed as a standard option in the settings but can be used via the "custom" exchange type if needed.

  • The "Custom Exchange Type" setting allows you to use exchange types not explicitly listed (like headers or any custom exchange type your RabbitMQ server might have).

  • Enabling "Wait for Confirmation" adds a layer of reliability, ensuring that your task is aware if a message was successfully received by the broker. However, it can slightly impact performance due to the added network round-trip.
  • It's important to handle the error output of this task to gracefully manage potential issues with RabbitMQ connectivity or message routing.