Produce test messages to a Hermes topic using the Kafka client

Produce test messages to a Hermes topic by configuring a producer client.

Before you begin

• Secure your Kafka topics by generating a ServiceNow® instance-signed certificate and keystore. You must provide truststore and keystore details when you configure the Hermes producer. See Set up a secure connection to the Hermes Messaging Service.
• Download and install Apache Kafka. See Prepare your Apache Kafka client environment.
• Create a test topic to store the test messages that you produce. For details, see Create a test topic in Hermes using the Kafka client.

Role required: admin

About this task

The following steps describe how to configure a producer client and send test messages to the Hermes Kafka cluster. Refer to these steps when you're ready to produce messages to Hermes for business or production purposes.

Procedure

1. Navigate to the config directory where you extracted Kafka.

   • For example, on Unix:

     cd /home/user/Software/kafka/config
     

   • For example, on Windows:

     cd C:\Software\kafka\config
     

2. Configure a producer.

   1. Open the producer.properties file.

   2. Configure the following SSL properties:

      security.protocol=SSL
      
      ssl.truststore.password=<truststore password>
      
      ssl.truststore.location=<path to truststore.p12>
      
      ssl.truststore.type=PKCS12
      
      ssl.keystore.password=<keystore password>
      
      ssl.keystore.location=<path to keystore.p12>
      
      ssl.keystore.type=PKCS12
      
      ssl.key.password=<keystore password>
      

      Replace the following placeholder variables:

      • <truststore password> with your truststore password
      • <path to truststore.p12> with the path to your truststore file
      • <keystore password> with your keystore password
      • <path to keystore.p12> with the path to your keystore file
        1. Save your changes in plain text.

3. Produce a test topic.

   1. Navigate to the Kafka directory.

   2. Run the following command:

      Unix:

      ./bin/kafka-console-producer.sh --topic snc.<instance_name>.<namespace>.sn_<app_id>.<topic_name> --producer.config ./config/producer.properties --bootstrap-server <instance_name>.service-now.com:4000,<instance_name>.service-now.com:4001,<instance_name>.service-now.com:4002,<instance_name>.service-now.com:4003
      

      Windows:

      bin\windows\kafka-console-producer.bat --topic snc.<instance_name>.<namespace>.sn_<app_id>.<topic_name> --producer.config config\producer.properties --bootstrap-server <instance_name>.service-now.com:4000,<instance_name>.service-now.com:4001,<instance_name>.service-now.com:4002,<instance_name>.service-now.com:4003
      

      Replace the following placeholder variables:

      • <instance_name> with your instance name
      • <namespace> with the namespace of the domain your Kafka topic belongs to (optional)
      • <app_id> with the application ID
      • <topic_name> with a unique test topic name Note: Each part of the topic name is case-sensitive.

   3. Send test messages to the test topic.

      For example:

      test1
      test2
      test3
      

Result

Test messages are produced to the test topic in the Hermes Kafka cluster.

What to do next

Consume test messages from a Hermes topic using the Kafka client