Actions11
Overview
This node interacts with NATS JetStream, a messaging system that supports streams and consumers for reliable message delivery. Specifically, the Consumer - List operation retrieves a list of consumers associated with a specified JetStream stream.
Use cases include:
- Monitoring existing consumers on a stream to manage message processing.
- Auditing or debugging consumer configurations.
- Integrating with workflows that need to dynamically react based on available consumers.
For example, you might use this node to fetch all consumers on a stream named "EVENTS" to check which applications are currently consuming messages from it.
Properties
| Name | Meaning |
|---|---|
| Stream Name | The name of the JetStream stream whose consumers you want to list. The stream must already exist before listing its consumers. |
Output
The output is an array of JSON objects representing the consumers on the specified stream. Each object contains details about a consumer such as its configuration and status (the exact structure depends on the JetStream API response).
Example output snippet (conceptual):
[
{
"name": "consumer1",
"stream": "EVENTS",
"config": { /* consumer configuration details */ },
"state": { /* consumer state information */ }
},
{
"name": "consumer2",
"stream": "EVENTS",
"config": { /* ... */ },
"state": { /* ... */ }
}
]
No binary data output is produced by this operation.
Dependencies
- Requires a valid connection to a NATS JetStream server.
- Needs an API key credential configured in n8n for authenticating with the NATS server.
- The target JetStream stream must already exist before listing consumers.
Troubleshooting
Common issues:
- Attempting to list consumers for a non-existent stream will likely cause an error.
- Network connectivity problems to the NATS server can cause failures.
- Insufficient permissions or invalid credentials will prevent successful connection.
Error messages:
"Unknown consumer operation: List"— indicates the operation name is incorrect or unsupported; ensure "List" is used exactly."NATS JetStream operation failed: <message>"— generic failure; check network, credentials, and stream existence."Unknown resource: consumers"— means the resource parameter is not set correctly; verify it is "consumers".
Resolutions:
- Verify the stream exists on the JetStream server before running the node.
- Confirm credentials and network access to the NATS server.
- Use correct property values matching the node's expected inputs.