Nats Trigger

Consume messages from a Nats subject

Overview

The Nats Trigger node listens for messages on a specified NATS subject and queue, emitting each received message into your n8n workflow. This node is useful for integrating real-time data streams or event-driven architectures with n8n, such as:

Reacting to events published by microservices via NATS.
Consuming messages from distributed systems for further processing in n8n.
Building automations that trigger on external system notifications.

Example use cases:

Automatically process new orders when an order service publishes to a "orders" subject.
Monitor IoT device updates sent to a specific NATS subject and trigger alerts or data storage workflows.

Properties

Name	Type	Meaning
Subject	String	Name of the NATS subject (queue/topic) to consume messages from.
Queue	String	The queue group name for load-balanced message consumption (default: `n8n_queue`).

Output

Each time a message is received on the specified subject and queue, the node emits an item with the following structure:

{
  "json": {
    // Decoded JSON content of the NATS message
    // Structure depends on what was published to the subject
  }
}

The output's json field contains the decoded JSON payload of the incoming NATS message.
No binary data is emitted by this node.

Dependencies

External Service: Requires access to a running NATS server/cluster.
Credentials: You must configure NATS credentials (natsApi) in n8n, including:
- Servers (comma-separated list)
- Optional authentication (username & password)
n8n Configuration: Ensure the node has network access to the NATS servers.

Troubleshooting

Common Issues:

Authentication Errors:
If username/password are required but not provided, you will see:
"Username and password are required for authentication"
Resolution: Check your NATS credentials configuration in n8n.
Connection Failures:
If the node cannot connect to the NATS server(s), ensure:
- The server addresses are correct and reachable.
- Network/firewall settings allow connections.
- Credentials are valid.
No Messages Received:
- Verify the subject and queue names match those used by publishers.
- Ensure messages are being published to the expected subject.