MQTT GeneralInstall

Summary

Publish a MQTT message to retrieve the text content of a web page element specified by a selector or XPath, optionally waiting for and returning a response message from a specified MQTT topic.

Inputs

• Topic (required) — The MQTT topic to publish the request to.
• QoS — The MQTT Quality of Service level to use for the publish.
• Include Input Items — Whether to include selected fields from the node's input items in the published payload under 'inputItems'.
• Include Input Items Fields — Comma or newline-separated list of input JSON fields to include when 'Include Input Items' is true.
• Wait For Response — Whether to wait for a reply message on a response topic before returning output.
• Response Topic (required) — The MQTT topic to listen for a response message if waiting for response; defaults to 'RES_'.
• Response Timeout (ms) — Maximum time in milliseconds to wait for the response message.
• Parse Response As JSON — Whether to attempt to parse the response payload as JSON.
• Target — A high-level selector string to identify the target element (for example, 'css=button').
• XPath — An explicit XPath selector to identify the target element if not using 'Target'.
• Timeout (sec) — The time in seconds to wait for the element text before timing out.

Output shape

a list of items mirroring input items or a single item if no input, each including an 'mqtt' JSON object containing the published topic, action information, input payload, and optionally the response data if 'Wait For Response' is enabled.

If 'Wait For Response' is enabled, the node subscribes to the specified response topic and waits up to the configured timeout to receive a response payload, which is included in the output under 'mqtt.response'. If no input items are supplied to the node, one output item with the payload is generated.

Links

• n8n community nodes installation guide