Overview
This node integrates with the NATS messaging system, allowing users to publish messages to a NATS server. The primary operation supported here is Publish, which sends a message with a specified subject and payload to the NATS server.
Common scenarios for this node include:
- Sending event notifications or alerts within distributed systems.
- Broadcasting messages to multiple subscribers in real-time applications.
- Integrating n8n workflows with microservices that communicate via NATS.
For example, you could use this node to publish a JSON payload notifying other services about a new user registration or to send commands to IoT devices subscribed to specific subjects.
Properties
| Name | Meaning |
|---|---|
| Subject | The subject (topic) on the NATS server to which the message will be published. |
| Payload Content Type | The type of the payload content. Options: "String" for plain text payloads, or "N8n Binary Data" for binary data payloads. |
| Payload | The actual message content as a string. Used when Payload Content Type is "String". |
| Payload Binary Property Name | The name of the binary property from input data to use as the payload. Used when Payload Content Type is "N8n Binary Data". |
| Headers | Optional HTTP-style headers to include with the published message. Supports multiple key-value pairs. |
Output
The node outputs an array of JSON objects representing the result of each publish action. Each output item corresponds to an input item processed by the node.
- The
jsonfield contains metadata about the publish operation, such as success confirmation or error details if publishing failed. - If binary data is used as payload, it is sent as-is to the NATS server; however, the output does not contain binary data itself but rather the status/result of the publish operation.
Dependencies
- Requires access to a NATS server instance.
- Needs an API authentication token or credentials configured in n8n to connect securely to the NATS server.
- Uses the official NATS client library internally (bundled in the node).
Troubleshooting
- Connection errors: Ensure the NATS server URL and credentials are correctly configured. Network issues or firewall restrictions can prevent connection.
- Publish failures: Check that the subject is valid and that the payload matches the expected format (string or binary). Invalid payload types or missing required properties may cause errors.
- Headers ignored: Some NATS servers or configurations might not support custom headers; verify server capabilities if headers do not appear to have effect.
- Binary payload issues: Confirm that the binary property name matches exactly the input binary data property; otherwise, the payload will be empty or invalid.