Use Apache Flink with Azure Event Hubs for Apache Kafka
This tutorial shows you how to connect Apache Flink to an event hub without changing your protocol clients or running your own clusters. For more information on Event Hubs' support for the Apache Kafka consumer protocol, see Event Hubs for Apache Kafka.
In this tutorial, you learn how to:
- Create an Event Hubs namespace
- Clone the example project
- Run Flink producer
- Run Flink consumer
Note
This sample is available on GitHub
Prerequisites
To complete this tutorial, make sure you have the following prerequisites:
- Read through the Event Hubs for Apache Kafka article.
- An Azure subscription. If you do not have one, create a free account before you begin.
- Java Development Kit (JDK) 1.7+
- On Ubuntu, run
apt-get install default-jdk
to install the JDK. - Be sure to set the JAVA_HOME environment variable to point to the folder where the JDK is installed.
- On Ubuntu, run
- Download and install a Maven binary archive
- On Ubuntu, you can run
apt-get install maven
to install Maven.
- On Ubuntu, you can run
- Git
- On Ubuntu, you can run
sudo apt-get install git
to install Git.
- On Ubuntu, you can run
Create an Event Hubs namespace
An Event Hubs namespace is required to send or receive from any Event Hubs service. See Creating an event hub for instructions to create a namespace and an event hub. Make sure to copy the Event Hubs connection string for later use.
Clone the example project
Now that you have the Event Hubs connection string, clone the Azure Event Hubs for Kafka repository and navigate to the flink
subfolder:
git clone https://github.com/Azure/azure-event-hubs-for-kafka.git
cd azure-event-hubs-for-kafka/tutorials/flink
Run Flink producer
Using the provided Flink producer example, send messages to the Event Hubs service.
Provide an Event Hubs Kafka endpoint
producer.config
Update the bootstrap.servers
and sasl.jaas.config
values in producer/src/main/resources/producer.config
to direct the producer to the Event Hubs Kafka endpoint with the correct authentication.
bootstrap.servers={YOUR.EVENTHUBS.FQDN}:9093
client.id=FlinkExampleProducer
sasl.mechanism=PLAIN
security.protocol=SASL_SSL
sasl.jaas.config=org.apache.kafka.common.security.plain.PlainLoginModule required \
username="$ConnectionString" \
password="{YOUR.EVENTHUBS.CONNECTION.STRING}";
Important
Replace {YOUR.EVENTHUBS.CONNECTION.STRING}
with the connection string for your Event Hubs namespace. For instructions on getting the connection string, see Get an Event Hubs connection string. Here's an example configuration: sasl.jaas.config=org.apache.kafka.common.security.plain.PlainLoginModule required username="$ConnectionString" password="Endpoint=sb://mynamespace.servicebus.windows.net/;SharedAccessKeyName=RootManageSharedAccessKey;SharedAccessKey=XXXXXXXXXXXXXXXX";
Run producer from the command line
To run the producer from the command line, generate the JAR and then run from within Maven (or generate the JAR using Maven, then run in Java by adding the necessary Kafka JAR(s) to the classpath):
mvn clean package
mvn exec:java -Dexec.mainClass="FlinkTestProducer"
The producer will now begin sending events to the event hub at topic test
and printing the events to stdout.
Run Flink consumer
Using the provided consumer example, receive messages from the event hub.
Provide an Event Hubs Kafka endpoint
consumer.config
Update the bootstrap.servers
and sasl.jaas.config
values in consumer/src/main/resources/consumer.config
to direct the consumer to the Event Hubs Kafka endpoint with the correct authentication.
bootstrap.servers={YOUR.EVENTHUBS.FQDN}:9093
group.id=FlinkExampleConsumer
sasl.mechanism=PLAIN
security.protocol=SASL_SSL
sasl.jaas.config=org.apache.kafka.common.security.plain.PlainLoginModule required \
username="$ConnectionString" \
password="{YOUR.EVENTHUBS.CONNECTION.STRING}";
Important
Replace {YOUR.EVENTHUBS.CONNECTION.STRING}
with the connection string for your Event Hubs namespace. For instructions on getting the connection string, see Get an Event Hubs connection string. Here's an example configuration: sasl.jaas.config=org.apache.kafka.common.security.plain.PlainLoginModule required username="$ConnectionString" password="Endpoint=sb://mynamespace.servicebus.windows.net/;SharedAccessKeyName=RootManageSharedAccessKey;SharedAccessKey=XXXXXXXXXXXXXXXX";
Run consumer from the command line
To run the consumer from the command line, generate the JAR and then run from within Maven (or generate the JAR using Maven, then run in Java by adding the necessary Kafka JAR(s) to the classpath):
mvn clean package
mvn exec:java -Dexec.mainClass="FlinkTestConsumer"
If the event hub has events (for example, if your producer is also running), then the consumer now begins receiving events from the topic test
.
Check out Flink's Kafka Connector Guide for more detailed information about connecting Flink to Kafka.
Next steps
To learn more about Event Hubs for Kafka, see the following articles: