Synchronizing Data from PgSQL to Kafka Using CDL

Scenario

This section describes how to import data from PgSQL to Kafka by using the CDLService web UI of a cluster with Kerberos authentication enabled in MRS 3.2.0.

Prerequisites

• The CDL and Kafka services have been installed in a cluster and are running properly.
• Write-ahead logging is enabled for the PostgreSQL database. For details, see Policy for Modifying Write-Ahead Logs in PostgreSQL Databases.
• You have created a human-machine user, for example, cdluser, added the user to user groups cdladmin (primary group), hadoop, and kafka, and associated the user with the System_administrator role on FusionInsight Manager.

Procedure

1. Log in to FusionInsight Manager as user cdluser (change the password upon the first login) and choose Cluster > Services > CDL. On the Dashboard page, click the hyperlink next to CDLService UI to go to the native CDL page.
2. Choose Link Management and click Add Link. On the displayed dialog box, set parameters for adding the pgsql and kafka links by referring to the following tables. Creating a CDL Database Connection describes the data link parameters.

   Table 1 PgSQL data link parameters

   Parameter	Example Value
   Link Type	pgsql
   Name	pgsqllink
   Host	10.10.10.10
   Port	5432
   DB Name	testDB
   User	user
   Password	Password of the user user
   Description	-

   Table 2 Kafka data link parameters

   Parameter	Example Value
   Link Type	kafka
   Name	kafkalink
   Description	-

3. After the parameters are configured, click Test to check whether the data link is normal.

   After the test is successful, click OK.

4. On the Job Management page, click Add Job. In the displayed dialog box, configure the parameters and click Next.
   Specifically:

   Parameter	Example Value
   Name	job_pgsqltokafka
   Desc	xxx

5. Configure PgSQL job parameters.
   1. On the Job Management page, drag the pgsql icon on the left to the editing area on the right and double-click the icon to go to the PgSQL job configuration page. For details about job parameters, see Creating a CDL Data Synchronization Job.

      Table 3 PgSQL job parameters

      Parameter	Example Value
      Link	pgsqllink
      Tasks Max	1
      Mode	insert, update, and delete
      Schema	public
      dbName Alias	cdc
      Slot Name	test_slot
      Slot Drop	No
      Connect With Hudi	No
      Use Exist Publication	Yes
      Publication Name	test

   2. Click the plus sign (+) to display more parameters.

      

      

      • WhiteList: Enter the name of the table in the database, for example, myclass.
      • Topic Table Mapping: In the first text box, enter a topic name (the value must be different from that of Name in 4), for example, myclass_topic. In the second text box, enter a table name, for example, myclass. The value must be in one-to-one relationship with the topic name entered in the first text box.)
   3. Click OK. The PgSQL job parameters are configured.

6. Configure Kafka job parameters.
   1. On the Job Management page, drag the kafka icon on the left to the editing area on the right and double-click the icon to go to the Kafka job configuration page. Configure parameters based on Table 4.

      Table 4 Kafka job parameter

      Parameter	Example Value
      Link	kafkalink

   2. Click OK.

7. After the job parameters are configured, drag the two icons to associate the job parameters and click Save. The job configuration is complete.

   

8. In the job list on the Job Management page, locate the created jobs, click Start in the Operation column, and wait until the jobs are started.

   Check whether the data transmission takes effect. For example, insert data into the table in the PgSQL database, go to the Kafka UI to check whether data is generated in the Kafka topic by referring to Viewing Kafka Data Production and Consumption Details.