MQTT GeneralInstall

Summary

Publish an MQTT message to command a mouse scroll action on a specific page element identified by a target selector or XPath, optionally waiting for and processing a response message.

Inputs

• Topic (required) — MQTT topic to which the scroll command is published.
• QoS — Quality of Service level for MQTT message delivery (0, 1, or 2).
• Include Input Items — Whether to include selected input fields from previous node items in the message payload.
• Include Input Items Fields — Comma-separated list of fields from previous input items to include when 'Include Input Items' is enabled.
• Wait For Response — Whether to wait for a reply message on a response topic before completing the node execution.
• Response Topic (required) — MQTT topic on which to listen for a reply if 'Wait For Response' is enabled; defaults to RES_.
• Response Timeout (ms) — Maximum wait time in milliseconds for a response message when waiting for a response.
• Parse Response As JSON — Whether to parse the received response payload as JSON.
• Target — High-level selector string identifying the target element to scroll (examples: 'id=scrollTarget', 'css=#scrollTarget').
• XPath — Explicit XPath selector for the target element if not using the 'Target' parser.
• Duration (ms) — Duration in milliseconds for the initial scroll action; subsequent scroll adjustments are computed automatically.
• Timeout (sec) — Time in seconds to wait for the target element to appear before returning an error.

Output shape

a list of items with the original input JSON extended by an 'mqtt' property detailing the topic, action, payload (scroll parameters), and optionally the response data if 'Wait For Response' is enabled.

If 'Wait For Response' is true, the node subscribes to the configured response topic and waits for a message or times out after the specified period. Included input fields are added to 'payload.inputItems' in the published MQTT message when enabled.

Examples

Example 1: Scroll a page element identified by CSS selector for 700 ms, publishing to topic 'playwright/mouse/scroll' with QoS 1.

Set 'Topic' to 'playwright/mouse/scroll', 'QoS' to 1, 'Target' to 'css=#scrollTarget', 'Duration (ms)' to 700, 'Timeout (sec)' to 5, and 'Wait For Response' to false.

Example 2: Scroll a page element identified by XPath, waiting for a response with a 10-second timeout.

Set 'Topic' to 'device/phone_01/scroll', 'XPath' to '//div[@id="scrollTarget"]', enable 'Wait For Response', set 'Response Topic' to 'RES_device/phone_01/scroll', and 'Response Timeout (ms)' to 10000.

Links

• n8n community nodes installation guide