RabbitMQ

Use RabbitMQ's Management HTTP API to publish and inspect messages, manage queue topology, and check broker health. Messages are published to exchanges and routed through bindings into queues.

The default acknowledgement mode requeues messages after reading them, so an inspection workflow can leave messages available to other consumers.

Before you start

The management plugin must be enabled and reachable from Sim. It listens on port 15672 by default and is separate from the AMQP port (5672). Self-hosted brokers enable it with rabbitmq-plugins enable rabbitmq_management; managed providers expose it as a management or console URL.
The management URL must use https unless the broker is on a loopback host. Credentials travel on every request as HTTP basic auth, so plain http to a remote broker would put them on the wire in the clear — Sim rejects it rather than sending them.
The user you authenticate as needs the management tag at minimum, plus read and write permissions on the virtual host you target. Administrative operations require broader permissions.
Publishing and reading messages over the HTTP API is convenient but not a high-throughput transport — RabbitMQ opens a new connection per request. It is well suited to workflow-rate traffic, inspection, and operational automation; a service consuming thousands of messages per second should use an AMQP client instead.
Queue statistics such as message and consumer counts are collected on an interval, so a queue declared moments ago may report them as empty until the broker's next sample.
Reading messages is bounded per call so one retrieval cannot exceed Sim's response limit. A batch is capped at 50 messages, payloads are truncated (each message reports whether it was), and a large batch shortens payloads further. AMQP properties and headers are returned in full — the broker offers no way to truncate them — so retrieving several messages carrying very large headers may still hit the limit; lower the count if that happens.

Use the block

Connect agents to a RabbitMQ broker through its Management HTTP API. Publish messages to exchanges, read messages off queues, declare queues, exchanges, bindings, and policies, and inspect broker health, queue depth, consumers, connections, and cluster nodes. Works with self-hosted brokers and managed offerings such as CloudAMQP as long as the management plugin is reachable.

Actions

RabbitMQ Publish Message

Publish a message to a RabbitMQ exchange with a routing key. Reports whether the message was routed to at least one queue.

Inputs and outputs

Parameter	Type	Required	Description
`host`	string	Yes	RabbitMQ Management API base URL, e.g. https://rabbit.example.com:15672. Must use https unless the broker is on a loopback host.
`username`	string	Yes	RabbitMQ username
`password`	string	Yes	RabbitMQ password
`vhost`	string	No	Virtual host to operate on. Defaults to /
`exchange`	string	No	Exchange to publish to. Leave empty to publish to the default exchange, which routes by queue name. Empty is a valid value, so this is not required.
`routingKey`	string	Yes	Routing key. When publishing to the default exchange this is the target queue name.
`payload`	string	Yes	Message body to publish
`payloadEncoding`	string	No	How the payload is encoded: string (default) or base64
`properties`	string	No	AMQP basic properties as a JSON object, e.g. {"delivery_mode":2,"content_type":"application/json"}
`headers`	string	No	Message headers as a JSON object, e.g. {"source":"sim"}

Parameter	Type	Required	Description
`host`	string	Yes	RabbitMQ Management API base URL, e.g. https://rabbit.example.com:15672. Must use https unless the broker is on a loopback host.
`username`	string	Yes	RabbitMQ username
`password`	string	Yes	RabbitMQ password
`vhost`	string	No	Virtual host to operate on. Defaults to /
`queue`	string	Yes	Queue to read messages from
`count`	number	No	Maximum number of messages to retrieve, from 1 to 50. Defaults to 1
`ackmode`	string	No	How retrieved messages are handled: ack_requeue_true (default, leaves messages in the queue), ack_requeue_false (removes them), reject_requeue_true, or reject_requeue_false
`encoding`	string	No	auto (default) returns readable text where possible, base64 always returns base64
`truncate`	number	No	Truncate payloads longer than this many bytes. Defaults to 50000, capped at 1000000, and lowered further at high counts so the whole batch stays inside the response limit. Each message reports whether it was truncated

Parameter	Type	Description
`queueName`	string	Queue the messages were read from
`count`	number	Number of messages retrieved
`messages`	array	Retrieved messages, empty when the queue holds nothing

Parameter	Type	Required	Description
`host`	string	Yes	RabbitMQ Management API base URL, e.g. https://rabbit.example.com:15672. Must use https unless the broker is on a loopback host.
`username`	string	Yes	RabbitMQ username
`password`	string	Yes	RabbitMQ password
`vhost`	string	No	Virtual host to operate on. Defaults to /
`page`	number	No	Page of results to return, starting at 1
`pageSize`	number	No	Queues per page, from 1 to 500. Defaults to 50
`name`	string	No	Filter queues whose name contains this value
`useRegex`	boolean	No	Treat the name filter as a regular expression

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RabbitMQ

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