Connection Management

NOTE

Verification Status: Tested and Verified against rekuiper engine on 2026-09-30 22:15:00 UTC.
The /connections REST endpoints allow defining and managing independent connection objects (mqtt, kafka, sql, etc.). In stream, table, and rule definitions, connections can be referenced via CONF_KEY or connectionSelector (supported as a first-class alias), which resolves configuration properties directly or from connections/{id}.

The rekuiper REST API manages shared connection profiles for sources and sinks. You can create, list, inspect, update, delete connections, and run connectivity health checks.

Manage Connections

Supported connection types include mqtt, nng, httppush, websocket, edgex, sql, and kafka.

Create a Connection

Use this endpoint to define a reusable connection profile:

POST http://localhost:9081/connections
Content-Type: application/json

Example MQTT connection:

{
  "id": "connection-1",
  "typ": "mqtt",
  "props": {
    "server": "tcp://127.0.0.1:1883"
  }
}

Example Kafka connection:

{
  "id": "kafka-1",
  "typ": "kafka",
  "props": {
    "brokers": "127.0.0.1:9092",
    "saslAuthType": "none"
  }
}

Update a Connection

Use this endpoint to update an existing connection profile:

PUT http://localhost:9081/connections/{id}
Content-Type: application/json

{
  "id": "connection-1",
  "typ": "mqtt",
  "props": {
    "server": "tcp://127.0.0.1:1883"
  }
}

NOTE

You cannot modify a connection profile while active rules reference it.

Get All Connections

Use this endpoint to retrieve all connection profiles and their runtime statuses:

GET http://localhost:9081/connections

Get a Single Connection Status

Use this endpoint to inspect the status of a specific connection:

GET http://localhost:9081/connections/{id}

Delete a Connection

Use this endpoint to delete a connection profile:

DELETE http://localhost:9081/connections/{id}

NOTE

You cannot delete a connection profile while active rules reference it. Stop or update dependent rules before deleting the connection.

NOTE

Compatibility Note: 404 Not Found vs 400 Bad Request for Missing Connections In legacy eKuiper, querying (GET /connections/{id}) or deleting (DELETE /connections/{id}) a non-existent connection ID returns 400 Bad Request. rekuiper strictly returns 404 Not Found.

Why we chose this difference: Per RFC 9110, HTTP 400 Bad Request indicates client syntax error (such as an unparseable body or missing mandatory fields), whereas 404 Not Found specifically indicates that the identified target resource does not exist. Using 404 allows client applications to cleanly detect missing connection profiles and automatically trigger provisioning or fallbacks without misinterpreting the error as a syntax malfunction.

Connectivity Health Checks

Test external endpoint reachability using these diagnostic endpoints:

Sink Connectivity Check

Use this endpoint to verify reachability and credential validity for a sink destination:

POST http://localhost:9081/metadata/sinks/connection/{sink}
Content-Type: application/json

Example MySQL SQL sink connectivity check:

{
  "url": "mysql://root@127.0.0.1:4000/test",
  "table": "test",
  "fields": ["a", "b", "c"]
}

Source Connectivity Check

Use this endpoint to verify reachability and credential validity for an upstream source:

POST http://localhost:9081/metadata/sources/connection/{source}
Content-Type: application/json

Example MySQL SQL source connectivity check:

{
  "url": "mysql://root@127.0.0.1:4000/test"
}