Line Messaging Trigger

Starts the workflow on a Line Messaging update

Overview

This node acts as a trigger for workflows based on events from the Line Messaging platform. It listens for incoming webhook events sent by Line and starts the workflow when specified event types occur. This is useful for automating responses or processing data triggered by user interactions or system events within Line messaging, such as receiving messages, users joining or leaving groups, postbacks, and more.

Practical examples include:

Automatically responding to new messages or commands sent by users.
Tracking when users follow or unfollow a Line account.
Handling postback actions triggered by buttons in Line chat.
Monitoring membership changes in group chats.

Properties

Name	Meaning
Trigger On	Select which Line Messaging events should trigger the workflow. Options include:
	- All (triggers on all events)
	- Message
	- Unsend
	- Follow
	- Unfollow
	- Join
	- Leave
	- MemberJoined
	- MemberLeft
	- Postback
	- VideoPlayComplete
	- Beacon
	- AccountLink
	- Membership

Output

The node outputs an array of JSON objects representing the events received from the Line webhook that match the selected trigger criteria.

The json output contains one or more event objects with details about each event.
Each event object corresponds to a single Line Messaging event, including its type and associated data.
No binary data output is produced by this node.

Dependencies

Requires a valid API authentication credential for the Line Messaging platform, including a channel secret used to verify webhook signatures.
The node expects to receive webhook POST requests from Line with a valid signature header (x-line-signature) to ensure authenticity.
The node uses an internal signature verification function to validate incoming requests against the channel secret.

Troubleshooting

Missing x-line-signature header: The node will throw an error if the webhook request does not contain the required signature header. Ensure that Line is correctly configured to send webhook events and that the HTTP headers are intact.
Missing channel secret in credentials: If the channel secret is not set in the node's credentials, the node cannot verify incoming requests and will error out. Verify that the API credential includes the channel secret.
Invalid signature: If the signature verification fails, the node responds with HTTP 403 Forbidden and does not trigger the workflow. This usually means the channel secret is incorrect or the request was tampered with.
No events matched: If no events match the selected trigger options, the node outputs an empty array, meaning the workflow will not proceed for those events.