org.apache.beam.sdk.io.mqtt

Class MqttIO

java.lang.Object

org.apache.beam.sdk.io.mqtt.MqttIO

public class MqttIO
extends java.lang.Object

An unbounded source for MQTT broker.

Reading from a MQTT broker

MqttIO source returns an unbounded PCollection containing MQTT message payloads (as byte[]).

To configure a MQTT source, you have to provide a MQTT connection configuration including ClientId, a ServerURI, a Topic pattern, and optionally username and password to connect to the MQTT broker. The following example illustrates various options for configuring the source:

 pipeline.apply(
   MqttIO.read()
    .withConnectionConfiguration(MqttIO.ConnectionConfiguration.create(
      "tcp://host:11883",
      "my_topic"))

 

Reading with Metadata from a MQTT broker

The readWithMetadata method extends the functionality of the basic read method by returning a PCollection of metadata that includes both the topic name and the payload. The metadata is encapsulated in a container class MqttRecord that includes the topic name and payload. This allows you to implement business logic that can differ depending on the topic from which the message was received.

 PCollection<MqttRecord> records = pipeline.apply(
   MqttIO.readWithMetadata()
    .withConnectionConfiguration(MqttIO.ConnectionConfiguration.create(
      "tcp://host:11883",
      "my_topic_pattern"))

 

By using the topic information, you can apply different processing logic depending on the source topic, enhancing the flexibility of message processing.

Example

{@code
 pipeline
   .apply(MqttIO.readWithMetadata()
     .withConnectionConfiguration(MqttIO.ConnectionConfiguration.create(
       "tcp://host:1883", "my_topic_pattern")))
   .apply(ParDo.of(new DoFn() {

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	MqttIO.ConnectionConfiguration A POJO describing a MQTT connection.
static class	MqttIO.Read<T> A PTransform to read from a MQTT broker.
static class	MqttIO.Write<InputT> A PTransform to write and send a message to a MQTT server.

Method Summary

Modifier and Type	Method and Description
static <InputT> MqttIO.Write<InputT>	dynamicWrite()
static MqttIO.Read<byte[]>	read()
static MqttIO.Read<MqttRecord>	readWithMetadata()
static MqttIO.Write<byte[]>	write()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

read

public static MqttIO.Read<byte[]> read()

readWithMetadata

public static MqttIO.Read<MqttRecord> readWithMetadata()

write

public static MqttIO.Write<byte[]> write()

dynamicWrite

public static <InputT> MqttIO.Write<InputT> dynamicWrite()