HiveMQ MongoDB Extension

This extension enables HiveMQ to store incoming MQTT messages directly into a MongoDB collection. This extension intercepts incoming MQTT Publish messages and inserts them into a specified MongoDB collection.

Prerequisites

1. HiveMQ MQTT broker installed and running.
2. MongoDB installed and running or an existing MongoDB Atlas cluster.

Build

To build the extension, follow these steps:

1. Clone the repository or download the source code.
2. Navigate to the project directory and build the project using your favorite build tool (Gradle or Maven). For Gradle, run ./gradlew build. For Maven, run mvn package.
3. The JAR file will be generated in the build/libs directory (Gradle) or target directory (Maven).

Installation

1. Create a new folder named hivemq-mongodb-extension inside the <HiveMQ-home>/extensions/ directory.

2. Copy the generated JAR file (e.g., your-extension.jar) and the extension.xml file from the project's src/main/resources folder into the newly created hivemq-mongodb-extension folder.

3. Edit the extension.xml file and update the connectionString and collectionName with your MongoDB settings.

   xmlCopy code

   <config> <mongoDbConfig> <connectionString>mongodb://username:password@your-mongodb-host:port/database</connectionString> <collectionName>mqtt_messages</collectionName> </mongoDbConfig> </config>

4. Restart HiveMQ to load the extension.

Testing

Use an MQTT client to publish messages to a topic on your HiveMQ broker. The messages will be stored directly into the specified MongoDB collection. You can use an MQTT client library or a tool like MQTT.fx or MQTT Explorer to publish and subscribe to messages.

Data Structure

The extension stores incoming MQTT messages in the MongoDB collection as documents with the following structure:

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{ "clientId": "example-client", "topic": "test/topic", "payload": "Hello, World!", "qos": 1, "retain": false, "timestamp": 1620133200000 }

• clientId: The client ID of the MQTT client that published the message.
• topic: The MQTT topic to which the message was published.
• payload: The payload of the MQTT message as a string.
• qos: The Quality of Service level of the message (0, 1, or 2).
• retain: A boolean indicating if the message has the retain flag set.
• timestamp: The timestamp (in milliseconds) when the message was received by the extension.