Community

Blog Events Webinars Tutorials Forum
  1. Blog
  2. Events
  3. Webinars
  4. Tutorials
  5. Forum
Create Account
×
Community Blog Change Data Capture (CDC) Made Easy- A Step-by-Step Guide with Debezium and Kafka

Change Data Capture (CDC) Made Easy- A Step-by-Step Guide with Debezium and Kafka

This article provides a detailed guide on implementing Change Data Capture (CDC) using Debezium and ApsaraMQ for Apache Kafka

by Aaron Berliano Handoko, Solution Architect Alibaba Cloud Indonesia

Introduction

In today's fast-paced data landscape, real-time integration is crucial for organizations to stay competitive. Change Data Capture (CDC) plays a vital role in this, allowing businesses to capture and propagate database changes instantly. Debezium, an open-source platform, excels in CDC by capturing changes from database transaction logs and converting them into a stream of events. This stream is seamlessly handled by ApsaraMQ for Apache Kafka, a distributed streaming platform known for its scalability and fault tolerance. Together, Debezium and Kafka provide a robust solution for real-time CDC, empowering organizations to make timely decisions based on the latest data insights.

Schema of the Experiment

1

Prerequisite

  1. Alibaba Cloud account already created. If you have not got an account, register here
  2. Elastic Compute Service (ECS) already been created.
  3. ApsaraMQ for Apache Kafka Professional Edition (High Write) already been created and configured
  4. RDS for Postgres has been created. In this experiment we used Postgres 13

Step by Step

1.  Configure ApsaraMQ for Apache Kafka

1.1. Getting Kafka Endpoint

You can simply get the kafka endpoint in the ApsaraMQ for Apache Kafka Console as shown in the picture below

2

1.2. Connection Whitelisting

Beside the endpoint there is an option to do ip whitelisting so we can connect debezium to the kafka instance from ECS. Please click the Manage Whitelist and add the ECS IP address

1.3. Creating Topic

On the left-hand side choose the item Topics and then click Create Topic. A menu should pop out from the right hand side to configure the topic.

3

Debezium requires kafka to have 3 essential topics named configs, status and offset. For these 3 topics, it is required to set their log cleanup policy as compact. Choose Local Storage and then choose Compact for Log Cleanup Policy.

In this example we will use the names custom_connect_configs, custom_connect_status and custom_connect_offsets

4

1.4. Creating Group ID

To create a group, simply choose the menu Groups and then Create Group. Fill in the Group ID that will be used to connect from debezium.

In this example we will name our group as connect-eb-cluster-custom

5

1.5. Enabling Automatic Topic Creation

Automatic Topic Creation is essential during the initial migration in order to eliminate the time used for topic creation. When using ApsaraMQ for Apache Kafka we need to enable the permission first. To do that simply go to the Instance Details then scroll down and enable the Automatic Topic Creation.

It will take about 15 minutes for the instance to apply this configuration.

6

2.  Configure RDS for PostgreSQL

2.1. Configure Connection

The endpoint of the RDS can be found inside Database Connection menu and next to the Internal Endpoint as shown below. Since the ECS and Kafka instance reside in the same VPC, we can use internal endpoint

7

2.2. Create an Account

Simply select the Account menu on the left-hand side and create database account.

8

2.3. Create a Database

To create a database simply select the Database menu on the left-hand side and create a database. In this example we create database called payment.

9

2.4. Create a Table

Log on to the Database by clicking the button as shown below. Fill out the necessary information needed including the account and password of the database.

10

Simply run the following query to create a sample table.

CREATE TABLE transaction(id SERIAL PRIMARY KEY, amount int, customerId varchar(36));

insert into transaction(id, amount,customerId) values(51, 12,'37b920fd-ecdd-7172-693a-d7be6db9792c');

3.  Connect to the ECS that is already been created and create a docker-compose.yml file. You can create a file by using vim docker-compose.yml command. This file will pull the docker image of the debezium to be used.

version: '3.1'
services:
    connector:
        image: debezium/connect:latest
        ports:
          - "8083:8083"
        environment:
          GROUP_ID: connect-eb-cluster-custom
          CONFIG_STORAGE_TOPIC: custom_connect_configs
          OFFSET_STORAGE_TOPIC: custom_connect_offsets
          STATUS_STORAGE_TOPIC: custom_connect_status
          BOOTSTRAP_SERVERS: <ApsaraMQ Kafka endpoint>

4.  After all the libraries have already been downloaded. Run this command below:

docker compose up

5.  If there is no error found when running the above command. Go to a new terminal and run the following command. This command is the configuration to create a connection from rds postgres to kafka via debezium.

curl -X POST -H "Accept:application/json" -H "Content-Type:application/json" localhost:8083/connectors/ -d '
{
 "name": "debezium-pg",
 "config": {
 "connector.class": "io.debezium.connector.postgresql.PostgresConnector",
 "tasks.max": "1",
 "database.hostname": "<your-rds-pg-endpoint>",
 "database.port": "5432",
 "database.user": "<your-db-user>",
 "database.password": "<your-db-password>",
 "database.dbname" : "<your-db-name>",
 "database.server.name": "<your-db-name>",
 "database.whitelist": "<your-db-name>",
 "database.history.kafka.bootstrap.servers": "<your-kafka-endpoint>",
 "database.history.kafka.topic": "schema-changes.payment",
 "topic.prefix":"<your-chosen-prefix>",
 "topic.creation.enable":"true",
 "topic.creation.default.replication.factor":12,
 "topic.creation.default.partitions":<num-partition>
 }
}'

6.  Check the log in the previous terminal and see if there is any error found. If no errors found you can go to the Kafka console and check if the topic has been automatically created.

7.  Insert data into the postgres database and see if the messages are able to be sent in real time to kafka.

insert into transaction(id, amount,customerId) values(1, 12,'TEST');

To check the message in Kafka go inside the topic and go to message query.

11

12
Example of Debezium CDC Message

8.  Helpful commands:

8.1. Edit debezium configuration

curl -X PUT -H "Accept:application/json" -H "Content-Type:application/json" localhost:8083/connectors/<name-of-connector>/config -d '
{
 "name": "debezium-pg",
 "config": {
 "connector.class": "io.debezium.connector.postgresql.PostgresConnector",
 "tasks.max": "1",
 "database.hostname": "<your-rds-pg-endpoint>",
 "database.port": "5432",
 "database.user": "<your-db-user>",
 "database.password": "<your-db-password>",
 "database.dbname" : "<your-db-name>",
 "database.server.name": "<your-db-name>",
 "database.whitelist": "<your-db-name>",
 "database.history.kafka.bootstrap.servers": "<your-kafka-endpoint>",
 "database.history.kafka.topic": "schema-changes.payment",
 "topic.prefix":"<your-chosen-prefix>",
 "topic.creation.enable":"true",
 "topic.creation.default.replication.factor":12,
 "topic.creation.default.partitions":<num-partition>
 }
}'

8.2. Restart debezium configuration

curl -X POST localhost:8083/connectors/<name-of-connector>/restart

Usefull Links

  1. Alibaba Cloud Kafka Connect Parameters
  2. Alibaba Cloud Worker Parameters
Big Data Data Analytics Tutorials Apache Kafka Change Data Capture CDC Debezium ApsaraMQ ApsaraMQ for Kafka
0 1 0
Share on

Read previous post:

Unlocking Real-Time Insights: Harnessing the Power of Alibaba Cloud Managed Flink for Real-time Data Processing

Read next post:

Optimize Global Application Performance with Intelligent DNS and GTM Integration

Alibaba Cloud Indonesia

100 posts | 17 followers

You may also like

Comments

Alibaba Cloud Indonesia

100 posts | 17 followers

Related Products

More Posts by Alibaba Cloud Indonesia

See All