Kafka connect synchronizes Kafka data to MySQL

One 、 Background information

Kafka Connect It is mainly used to input and output data streams to message queues Kafka edition .Kafka Connect Mainly through various Source Connector The implementation of the , Input data from a third-party system into Kafka Broker, Through a variety of Sink Connector Realization , Take data from Kafka Broker Import into the third-party system .

Official documents ：How to use Kafka Connect - Getting Started | Confluent Documentation

Two 、 development environment

middleware	edition
zookeeper	3.7.0
kafka	2.10-0.10.2.1

3、 ... and 、 To configure Kafka Connect

1、 Enter kafka Of config Under the folder , modify connect-standalone.properties

# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
 
# These are defaults. This file just demonstrates how to override some settings.
bootstrap.servers=kafka-0:9092
 
# The converters specify the format of data in Kafka and how to translate it into Connect data. Every Connect user will
# need to configure these based on the format they want their data in when loaded from or stored into Kafka
key.converter=org.apache.kafka.connect.json.JsonConverter
value.converter=org.apache.kafka.connect.json.JsonConverter
# Converter-specific settings can be passed in by prefixing the Converter's setting with the converter we want to apply
# it to
key.converter.schemas.enable=false
value.converter.schemas.enable=false
 
# The internal converter used for offsets and config data is configurable and must be specified, but most users will
# always want to use the built-in default. Offset and config data is never visible outside of Kafka Connect in this format.
internal.key.converter=org.apache.kafka.connect.json.JsonConverter
internal.value.converter=org.apache.kafka.connect.json.JsonConverter
internal.key.converter.schemas.enable=false
internal.value.converter.schemas.enable=false
 
offset.storage.file.filename=/tmp/connect.offsets
# Flush much faster than normal, which is useful for testing/debugging
offset.flush.interval.ms=10000
#  The core configuration 
#plugin.path=/home/kafka/plugins

If Mysql Data synchronization to Kafka, The following information needs to be modified ：

# The converters specify the format of data in Kafka and how to translate it into Connect data. Every Connect user will
# need to configure these based on the format they want their data in when loaded from or stored into Kafka
key.converter=io.confluent.connect.json.JsonSchemaConverter
value.converter=io.confluent.connect.json.JsonSchemaConverter
# Converter-specific settings can be passed in by prefixing the Converter's setting with the converter we want to apply
# it to
key.converter.schemas.enable=true
value.converter.schemas.enable=true

Be careful ：Kafka Connect The previous version of does not support configuration plugin.path, You need to CLASSPATH Specify the plug-in location in

vi /etc/profile
export CLASSPATH=/home/kafka/*
source /etc/profile

2、 modify connect-mysql-source.properties（mysql-kafka）

#
# Copyright 2018 Confluent Inc.
#
# Licensed under the Confluent Community License (the "License"); you may not use
# this file except in compliance with the License.  You may obtain a copy of the
# License at
#
# http://www.confluent.io/confluent-community-license
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OF ANY KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations under the License.
#

# A simple example that copies all tables from a SQLite database. The first few settings are
# required for all connectors: a name, the connector class to run, and the maximum number of
# tasks to create:
name=test-source-mysql
connector.class=io.confluent.connect.jdbc.JdbcSourceConnector
tasks.max=1
# The remaining configs are specific to the JDBC source connector. In this example, we connect to a
# SQLite database stored in the file test.db, use and auto-incrementing column called 'id' to
# detect new rows as they are added, and output to topics prefixed with 'test-sqlite-jdbc-', e.g.
# a table called 'users' will be written to the topic 'test-sqlite-jdbc-users'.
connection.url=jdbc:mysql://localhost:3306/demo?user=root&password=root
table.whitelist=test
mode=incrementing
incrementing.column.name=id
topic.prefix=mysql-

# Define when identifiers should be quoted in DDL and DML statements.
# The default is 'always' to maintain backward compatibility with prior versions.
# Set this to 'never' to avoid quoting fully-qualified or simple table and column names.
#quote.sql.identifiers=always

Related drive jar package ：

kafka- Related driver package -Java Document resources -CSDN download

3、 modify connect-mysql-sink.properties（kafka-mysql）

#
# Copyright 2018 Confluent Inc.
#
# Licensed under the Confluent Community License (the "License"); you may not use
# this file except in compliance with the License.  You may obtain a copy of the
# License at
#
# http://www.confluent.io/confluent-community-license
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OF ANY KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations under the License.
#

# A simple example that copies from a topic to a SQLite database.
# The first few settings are required for all connectors:
# a name, the connector class to run, and the maximum number of tasks to create:
name=test-sink
connector.class=io.confluent.connect.jdbc.JdbcSinkConnector
tasks.max=1

# The topics to consume from - required for sink connectors like this one
topics=mysql-test_to_kafka

# Configuration specific to the JDBC sink connector.
# We want to connect to a SQLite database stored in the file test.db and auto-create tables.
connection.url=jdbc:mysql://localhost:3306/demo?user=root&password=root
auto.create=false
pk.mode=record_value
pk.fields=id
table.name.format=test_kafka_to
#delete.enabled=true
#  Write mode 
insert.mode=upsert

# Define when identifiers should be quoted in DDL and DML statements.
# The default is 'always' to maintain backward compatibility with prior versions.
# Set this to 'never' to avoid quoting fully-qualified or simple table and column names.
#quote.sql.identifiers=always

Four 、 Start command

bin/connect-standalone.sh config/connect-standalone.properties config/connect-mysql-source.properties config/connect-mysql-sink.properties