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CDC Canal Connector

Source Configuration Options​

The Configuration is mostly related to Canal task config.

NameRequiredDefaultDescription
zkServersfalse127.0.0.1:2181The address and port of the zookeeper . if canal server configured to cluster mode
batchSizetrue5120Take 5120 records from the canal server in batches
usernamefalse``Canal server account, not MySQL
passwordfalse``Canal server password, not MySQL
clusterfalsefalseDecide whether to open cluster mode based on canal server configuration, true: cluster mode, false: standalone mode
singleHostnamefalse127.0.0.1The address of canal server
singlePortfalse11111The port of canal server

Configuration Example​

Here is a configuration Json example:


{
"zkServers": "127.0.0.1:2181",
"batchSize": "5120",
"destination": "example",
"username": "",
"password": "",
"cluster": false,
"singleHostname": "127.0.0.1",
"singlePort": "11111",
}

You could also find the yaml example in this file, which has similar content below:


configs:
zkServers: "127.0.0.1:2181"
batchSize: "5120"
destination: "example"
username: ""
password: ""
cluster: false
singleHostname: "127.0.0.1"
singlePort: "11111"

Usage example​

Here is a simple example to store MySQL change data using above example config.

  • Start a MySQL server

docker pull mysql:5.7
docker run -d -it --rm --name pulsar-mysql -p 3306:3306 -e MYSQL_ROOT_PASSWORD=canal -e MYSQL_USER=mysqluser -e MYSQL_PASSWORD=mysqlpw mysql:5.7

  • Modify configuration files mysqld.cnf

[mysqld]
pid-file = /var/run/mysqld/mysqld.pid
socket = /var/run/mysqld/mysqld.sock
datadir = /var/lib/mysql
#log-error = /var/log/mysql/error.log
# By default we only accept connections from localhost
#bind-address = 127.0.0.1
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
log-bin=mysql-bin
binlog-format=ROW
server_id=1

  • Copy file to mysql server from local and restart mysql server

docker cp mysqld.cnf pulsar-mysql:/etc/mysql/mysql.conf.d/
docker restart pulsar-mysql

  • Create test database in mysql server

docker exec -it pulsar-mysql /bin/bash
mysql -h 127.0.0.1 -uroot -pcanal -e 'create database test;'

  • Start canal server and connect mysql server

docker pull canal/canal-server:v1.1.2
docker run -d -it --link pulsar-mysql -e canal.auto.scan=false -e canal.destinations=test -e canal.instance.master.address=pulsar-mysql:3306 -e canal.instance.dbUsername=root -e canal.instance.dbPassword=canal -e canal.instance.connectionCharset=UTF-8 -e canal.instance.tsdb.enable=true -e canal.instance.gtidon=false --name=pulsar-canal-server -p 8000:8000 -p 2222:2222 -p 11111:11111 -p 11112:11112 -m 4096m canal/canal-server:v1.1.2

  • Start pulsar standalone

docker pull apachepulsar/pulsar:2.4.2
docker run -d -it --link pulsar-canal-server -p 6650:6650 -p 8080:8080 -v $PWD/data:/pulsar/data --name pulsar-standalone apachepulsar/pulsar:2.4.2 bin/pulsar standalone

  • Start pulsar-io in standalone

  • Config file canal-mysql-source-config.yaml


configs:
zkServers: ""
batchSize: "5120"
destination: "test"
username: ""
password: ""
cluster: false
singleHostname: "pulsar-canal-server"
singlePort: "11111"

  • Consumer file pulsar-client.py for test

import pulsar

client = pulsar.Client('pulsar://localhost:6650')
consumer = client.subscribe('my-topic',
subscription_name='my-sub')

while True:
msg = consumer.receive()
print("Received message: '%s'" % msg.data())
consumer.acknowledge(msg)

client.close()

  • Copy config file and test file to pulsar server

docker cp canal-mysql-source-config.yaml pulsar-standalone:/pulsar/conf/
docker cp pulsar-client.py pulsar-standalone:/pulsar/

  • Download canal connector and start canal connector

docker exec -it pulsar-standalone /bin/bash
wget http://apache.01link.hk/pulsar/pulsar-2.4.2/connectors/pulsar-io-canal-2.4.2.nar -P connectors
./bin/pulsar-admin sources localrun --archive ./connectors/pulsar-io-canal-2.4.2.nar --classname org.apache.pulsar.io.canal.CanalStringSource --tenant public --namespace default --name canal --destination-topic-name my-topic --source-config-file /pulsar/conf/canal-mysql-source-config.yaml --parallelism 1

  • Consumption data

docker exec -it pulsar-standalone /bin/bash
python pulsar-client.py

  • Open another window for login mysql server

docker exec -it pulsar-mysql /bin/bash
mysql -h 127.0.0.1 -uroot -pcanal

  • Create table and insert, delete, update data in mysql server

mysql> use test;
mysql> show tables;
mysql> CREATE TABLE IF NOT EXISTS `test_table`(`test_id` INT UNSIGNED AUTO_INCREMENT,`test_title` VARCHAR(100) NOT NULL,
`test_author` VARCHAR(40) NOT NULL,
`test_date` DATE,PRIMARY KEY ( `test_id` ))ENGINE=InnoDB DEFAULT CHARSET=utf8;
mysql> INSERT INTO test_table (test_title, test_author, test_date) VALUES("a", "b", NOW());
mysql> UPDATE test_table SET test_title='c' WHERE test_title='a';
mysql> DELETE FROM test_table WHERE test_title='c';