MQTT Source Connector for Confluent Platform¶
The Kafka Connect MQTT Source connector connects to a MQTT broker and subscribes to the specified topics. SSL is supported. For information on how to create SSL keys and certificates, see Creating SSL Keys and Certificates. For the relevant configuration properties, see the MQTT Source connector configuration reference.
Features¶
At least once delivery¶
This connector guarantees that records are delivered to the Kafka topic at least once. If the connector restarts, there may be some duplicate records in the Kafka topic.
Multiple tasks¶
The MQTT Source connector supports running one or more tasks. You can specify
the number of tasks in the tasks.max
configuration parameter. This can lead
to huge performance gains when multiple files need to be parsed.
Configuration Properties¶
For a complete list of configuration properties for this source connector, see MQTT Source Connector Configuration Properties.
Note
For an example of how to get Kafka Connect connected to Confluent Cloud, see Distributed Cluster.
Usage Notes¶
If you need to change the topic take a look at the RegexRouter transformation which can be used to change the topic name before it is written to Apache Kafka®.
The output of this connector is an envelope with all of the properties of the incoming message. The body of the message is written to the value as bytes. The key is the topic the message was written to.
Examples¶
Property-based example¶
This configuration is used typically along with standalone workers.
name=MqttSourceConnector1
connector.class=io.confluent.connect.mqtt.MqttSourceConnector
tasks.max=1
mqtt.server.uri=< Required Configuration >
mqtt.topics=< Required Configuration >
REST-based example¶
This configuration is used typically along with distributed workers.
Write the following json to connector.json
, configure all of the required values, and use the command below to
post the configuration to one the distributed connect worker(s). Check here for more information about the
Kafka Connect REST API
Connect Distributed REST example:
{
"config" : {
"name" : "MqttSourceConnector1",
"connector.class" : "io.confluent.connect.mqtt.MqttSourceConnector",
"tasks.max" : "1",
"mqtt.server.uri" : "< Required Configuration >",
"mqtt.topics" : "< Required Configuration >"
}
}
Use curl to post the configuration to one of the Kafka Connect Workers. Change http://localhost:8083/ the endpoint of one of your Kafka Connect worker(s).
Create a new connector:
curl -s -X POST -H 'Content-Type: application/json' --data @connector.json http://localhost:8083/connectors
Update an existing connector:
curl -s -X PUT -H 'Content-Type: application/json' --data @connector.json http://localhost:8083/connectors/MqttSourceConnector1/config