http-signaling-notification

HTTP Signaling and Notification

This example demonstrates how to create custom signaling and notification channels for Debezium connectors. It discusses how to create and utilize the HTTP signal and notification channels using the Debezium Postgres connector, a Mock Server, and Postbin which is used as the HTTP endpoint to receive the notifications. It accompanies the blog post Debezium signaling and notifications - Part 2: Customisation.

Building

Prepare the Java components by first performing a Maven build.

$ mvn clean install

Environment

Setup the necessary environment variables

$ export DEBEZIUM_VERSION=2.3

The DEBEZIUM_VERSION specifies which version of Debezium artifacts should be used, which should 2.3 or later.

Run the services

Start all components:

$ docker-compose up -d

This executes all configurations set forth by the docker-compose.yaml file.

Configure the Debezium connector

Register Postgres Debezium connector to start streaming changes from the database:

$ curl -i -X POST -H "Accept:application/json" \
    -H  "Content-Type:application/json" http://localhost:8083/connectors/ \
    -d @register-postgres.json

Signal and Notification events

Once the connector is running, you can see signal event sent to the connector via Mock Server through the endpoint:

Recorded signal event 'SignalRecord{id='924e3ff8-2245-43ca-ba77-2af9af02fa07', type='log', data='{"message":"Signal message received from http endpoint."}', additionalData={}}'    [io.debezium.examples.signal.HttpSignalChannel]

You can also see notification event sent from the connector to the endpoint via Postbin:

[HTTP NOTIFICATION SERVICE] Sending notification to http channel   [io.debezium.examples.notification.HttpNotificationChannel]

Bin created: {"binId":"1688742588469-1816775151528","now":1688742588470,"expires":1688744388470}   [io.debezium.examples.notification.HttpNotificationChannel]

Using the binId from the notification event, you can see the notification event sent to the endpoint in Postbin. To view the notification event, you can access Postbin using the following URL: https://www.toptal.com/developers/postbin/b/:binId. Replace :binId in the URL with the actual binId obtained from the connector logs.

Stop the services

Stop all components:

$ docker-compose down