MQTT GeneralInstall

Summary

Publish a 'Refresh' command to control a connected browser via MQTT by sending a payload to a specified MQTT topic, optionally including input fields, and optionally waiting for a response on a designated topic.

Inputs

• Topic (required) — MQTT topic used to publish the 'Refresh' command for browser control.
• QoS — MQTT Quality of Service level for message delivery (0, 1, or 2).
• Include Input Items — Whether to include selected fields from incoming input items in the payload as 'inputItems'.
• Include Input Items Fields — Comma- or newline-separated list of fields from previous input items to include in the payload under 'inputItems' if 'Include Input Items' is enabled.
• Wait For Response — Whether to wait for a reply message on a response topic before returning node output.
• Response Topic (required) — MQTT topic to subscribe to for receiving the response message if 'Wait For Response' is enabled; defaults to 'RES_' prefix plus the Publish topic.
• Response Timeout (ms) — Maximum time in milliseconds to wait for a response message if 'Wait For Response' is enabled.
• Parse Response As JSON — Whether to attempt to parse the response payload as JSON if a response is received.

Output shape

a list of items equal in count to the input items if any, or a single item otherwise, each containing the original input JSON plus an 'mqtt' property describing the published topic, action, payload inputs, and optionally the response data if received.

If 'Wait For Response' is enabled, the node subscribes to the response topic and waits up to the Response Timeout for a reply before continuing. If disabled, the node publishes the 'Refresh' action payload and immediately returns. The payload includes an 'action' key with the 'Refresh' operation details and any input fields specified. Errors during MQTT connection or publish are reported and can be handled via 'Continue on Fail' behavior.

Examples

Example 1: Publish a refresh command to a browser via MQTT without waiting for a response.

Set 'Topic' to the MQTT topic for command delivery, choose 'QoS' level, and ensure 'Wait For Response' is disabled.

Example 2: Publish a refresh command while including selected input fields and wait for a confirmation response.

Enable 'Include Input Items', specify fields to include, enable 'Wait For Response', set 'Response Topic' (default prefixed), and adjust 'Response Timeout' and 'Parse Response As JSON' as needed.

Links

• n8n community nodes installation guide