mqtt2http

MQTT broker with hooks to send authentication and publish events as HTTP requests.

This MQTT broker receives MQTT messages with a topic on port 1883 and forwards them as POST requests to an HTTP service (see MQTT2HTTP_PUBLISH_URL). The topic is either included in the URL or forwarded as the HTTP header X-Topic (see MQTT2HTTP_TOPIC_HEADER for customization). When a client connects to the broker, it will send an HTTP POST request to MQTT2HTTP_AUTHORIZE_URL with the client credentials as HTTP Basic Auth to validate the username and password.

http2mqtt

There is also an API endpoint available to be used as http2mqtt at http://localhost:8080/publish?topic=... (see MQTT2HTTP_HTTP_LISTEN_ADDRESS to customize the port). It will publish the body of a POST request to the topic passed as query parameter. The service requires HTTP Basic authentication.

curl --user username:password -X POST -d '{"test": true}' http://mqtt2http:8080/publish?topic=test

This example will publish the message {"test": true} to the topic test.

Run with Docker

This tool is published as amm0nite/mqtt2http on Docker Hub. You can run it, for example, using Docker Compose:

mqtt2http:
  image: "docker.io/amm0nite/mqtt2http:latest"
  restart: "unless-stopped"
  ports:
    - 1883:1883
    - 8088:8080
    - 9090:9090
  environment:
    MQTT2HTTP_AUTHORIZE_URL: http://auth.service/
    MQTT2HTTP_PUBLISH_URL: http://backend.service/api/{topic}

This will expose the MQTT port (1883), the HTTP publish interface (on port 8080), and a Prometheus metrics endpoint (on port 9090).

Configuration

The mqtt2http tool provides several configuration options:

• MQTT2HTTP_MQTT_LISTEN_ADDRESS

  Default: :1883

  The TCP address (host:port) on which the embedded MQTT broker will listen for client connections.

• MQTT2HTTP_HTTP_LISTEN_ADDRESS

  Default: :8080

  The HTTP address (host:port) for the built-in REST API (/publish endpoint).

• MQTT2HTTP_AUTHORIZE_URL

  Default: http://example.com

  The URL to which mqtt2http will POST (with Basic Auth headers) whenever a client attempts to CONNECT. A 200 or 201 response means “allow”; any other response is treated as a failure.

• MQTT2HTTP_PUBLISH_URL

  Default: http://example.com/{topic}

  The URL template used when forwarding published messages. The {topic} placeholder is replaced with the actual MQTT topic name (optional).

• MQTT2HTTP_CONTENT_TYPE

  Default: application/octet-stream

  The Content-Type header used in the HTTP POST when forwarding the raw payload of a PUBLISH packet. Example: if the message is a JSON string, set this to application/json.

• MQTT2HTTP_TOPIC_HEADER

  Default: X-Topic

  The name of the custom HTTP header in which the MQTT topic name will be sent during a PUBLISH POST.

• MQTT2HTTP_METRICS_HTTP_LISTEN_ADDRESS

  Default: :9090

  The HTTP address (host:port) on which the Prometheus metrics endpoint (/metrics) will be exposed.

Minimum Required Configuration

To use mqtt2http in a meaningful way, at least the following environment variables must be set:

MQTT2HTTP_AUTHORIZE_URL=http://...
MQTT2HTTP_PUBLISH_URL=http://...