SpringBoot之Canal同步数据库
SpringBoot之Canal同步数据库
介绍
通过实时同步数据库表的方式实现，例如我们要统计每天注册与登录人数，我们只需把会员表同步到统计库中，实现本地统计就可以了，这样效率更高，耦合度更低，Canal就是一个很好的数据库同步工具。 canal是阿里巴巴旗下的一款开源项目，纯Java开发。基于数据库增量日志解析，提供增量数据订阅&消费，目前主要支持了MySQL。
本地数据库和服务器上数据库保持一致，本地添加内容，服务器上面数据库也会自动添加内容
1.Canal环境搭建
1）检查binlog功能是否有开启
show variables like 'log_bin';
2）如果显示状态为OFF表示该功能未开启，开启binlog功能
1，修改 mysql 的配置文件 my.cnf
vi /etc/my.cnf
追加内容：
log-bin=mysql-bin #binlog文件名
binlog_format=ROW #选择row模式
server_id=1 #mysql实例id,不能和canal的slaveId重复
2，重启 mysql：
service mysql restart
3,再次检测是否开启
show variables like 'log_bin';
2.安装Canal
1）下载之后，放到目录中，解压文件
cd /usr/local/canal
tar zxvf canal.deployer-1.1.4.tar.gz
2）修改配置文件
vi conf/example/instance.properties
#需要改成自己的数据库信息
canal.instance.master.address=119.3.109.93:3306
#需要改成自己的数据库用户名与密码
canal.instance.dbUsername=root
canal.instance.dbPassword=123456
#需要改成同步的数据库表规则，例如只是同步一下表，第一条是全部，第二条是选择其中一个表，看自己需要
#canal.instance.filter.regex=.*\\..*
canal.instance.filter.regex=guli_ucenter.ucenter_member
3.启动Canal
./startup.sh
4.创建Canal模块，并引入依赖，版本在我主模块那里，这个只是引入，Canal的版本是1.1.0
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!--mysql-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>commons-dbutils</groupId>
<artifactId>commons-dbutils</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<dependency>
<groupId>com.alibaba.otter</groupId>
<artifactId>canal.client</artifactId>
</dependency>
</dependencies>
5.添加配置文件
# 服务端口
server.port=10000
# 服务名
spring.application.name=canal-client
# 环境设置：dev、test、prod
spring.profiles.active=dev
# mysql数据库连接
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/guli?serverTimezone=GMT%2B8
spring.datasource.username=root
spring.datasource.password=123456
6.创建canal客户端类，修改服务器ip就行，其他是固定的内容
import com.alibaba.otter.canal.client.CanalConnector;
import com.alibaba.otter.canal.client.CanalConnectors;
import com.alibaba.otter.canal.protocol.CanalEntry.*;
import com.alibaba.otter.canal.protocol.Message;
import com.google.protobuf.InvalidProtocolBufferException;
import org.apache.commons.dbutils.DbUtils;
import org.apache.commons.dbutils.QueryRunner;
import org.springframework.stereotype.Component;
import javax.annotation.Resource;
import javax.sql.DataSource;
import java.net.InetSocketAddress;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Iterator;
import java.util.List;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;
@Component
public class CanalClient {
//sql队列
private Queue<String> SQL_QUEUE = new ConcurrentLinkedQueue<>();
@Resource
private DataSource dataSource;
/**
* canal入库方法
*/
public void run() {
CanalConnector connector = CanalConnectors.newSingleConnector(new
InetSocketAddress("119.3.109.93",
11111), "example", "", "");
int batchSize = 1000;
try {
connector.connect();
connector.subscribe(".*\\..*");
connector.rollback();
try {
while (true) {
//尝试从master那边拉去数据batchSize条记录，有多少取多少
Message message = connector.getWithoutAck(batchSize);
long batchId = message.getId();
int size = message.getEntries().size();
if (batchId == -1 || size == 0) {
Thread.sleep(1000);
} else {
dataHandle(message.getEntries());
}
connector.ack(batchId);
//当队列里面堆积的sql大于一定数值的时候就模拟执行
if (SQL_QUEUE.size() >= 1) {
executeQueueSql();
}
}
} catch (InterruptedException e) {
e.printStackTrace();
} catch (InvalidProtocolBufferException e) {
e.printStackTrace();
}
} finally {
connector.disconnect();
}
}
/**
* 模拟执行队列里面的sql语句
*/
public void executeQueueSql() {
int size = SQL_QUEUE.size();
for (int i = 0; i < size; i++) {
String sql = SQL_QUEUE.poll();
System.out.println("[sql]----> " + sql);
this.execute(sql.toString());
}
}
/**
* 数据处理
*
* @param entrys
*/
private void dataHandle(List<Entry> entrys) throws
InvalidProtocolBufferException {
for (Entry entry : entrys) {
if (EntryType.ROWDATA == entry.getEntryType()) {
RowChange rowChange = RowChange.parseFrom(entry.getStoreValue());
EventType eventType = rowChange.getEventType();
if (eventType == EventType.DELETE) {
saveDeleteSql(entry);
} else if (eventType == EventType.UPDATE) {
saveUpdateSql(entry);
} else if (eventType == EventType.INSERT) {
saveInsertSql(entry);
}
}
}
}
/**
* 保存更新语句
*
* @param entry
*/
private void saveUpdateSql(Entry entry) {
try {
RowChange rowChange = RowChange.parseFrom(entry.getStoreValue());
List<RowData> rowDatasList = rowChange.getRowDatasList();
for (RowData rowData : rowDatasList) {
List<Column> newColumnList = rowData.getAfterColumnsList();
StringBuffer sql = new StringBuffer("update " +
entry.getHeader().getTableName() + " set ");
for (int i = 0; i < newColumnList.size(); i++) {
sql.append(" " + newColumnList.get(i).getName()
+ " = '" + newColumnList.get(i).getValue() + "'");
if (i != newColumnList.size() - 1) {
sql.append(",");
}
}
sql.append(" where ");
List<Column> oldColumnList = rowData.getBeforeColumnsList();
for (Column column : oldColumnList) {
if (column.getIsKey()) {
//暂时只支持单一主键
sql.append(column.getName() + "=" + column.getValue());
break;
}
}
SQL_QUEUE.add(sql.toString());
}
} catch (InvalidProtocolBufferException e) {
e.printStackTrace();
}
}
/**
* 保存删除语句
*
* @param entry
*/
private void saveDeleteSql(Entry entry) {
try {
RowChange rowChange = RowChange.parseFrom(entry.getStoreValue());
List<RowData> rowDatasList = rowChange.getRowDatasList();
for (RowData rowData : rowDatasList) {
List<Column> columnList = rowData.getBeforeColumnsList();
StringBuffer sql = new StringBuffer("delete from " +
entry.getHeader().getTableName() + " where ");
for (Column column : columnList) {
if (column.getIsKey()) {
//暂时只支持单一主键
sql.append(column.getName() + "=" + column.getValue());
break;
}
}
SQL_QUEUE.add(sql.toString());
}
} catch (InvalidProtocolBufferException e) {
e.printStackTrace();
}
}
/**
* 保存插入语句
*
* @param entry
*/
private void saveInsertSql(Entry entry) {
try {
RowChange rowChange = RowChange.parseFrom(entry.getStoreValue());
List<RowData> rowDatasList = rowChange.getRowDatasList();
for (RowData rowData : rowDatasList) {
List<Column> columnList = rowData.getAfterColumnsList();
StringBuffer sql = new StringBuffer("insert into " +
entry.getHeader().getTableName() + " (");
for (int i = 0; i < columnList.size(); i++) {
sql.append(columnList.get(i).getName());
if (i != columnList.size() - 1) {
sql.append(",");
}
}
sql.append(") VALUES (");
for (int i = 0; i < columnList.size(); i++) {
sql.append("'" + columnList.get(i).getValue() + "'");
if (i != columnList.size() - 1) {
sql.append(",");
}
}
sql.append(")");
SQL_QUEUE.add(sql.toString());
}
} catch (InvalidProtocolBufferException e) {
e.printStackTrace();
}
}
/**
* 入库
* @param sql
*/
public void execute(String sql) {
Connection con = null;
try {
if(null == sql) return;
con = dataSource.getConnection();
QueryRunner qr = new QueryRunner();
int row = qr.execute(con, sql);
System.out.println("update: "+ row);
} catch (SQLException e) {
e.printStackTrace();
} finally {
DbUtils.closeQuietly(con);
}
}
}
7.启动类需要继承方法
import com.mine.guli.client.CanalClient;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import javax.annotation.Resource;
@SpringBootApplication
public class CanalApplication implements CommandLineRunner {
@Resource
private CanalClient canalClient;
public static void main(String[] args) {
SpringApplication.run(CanalApplication.class, args);
}
@Override
public void run(String... strings) throws Exception {
//项目启动，执行canal客户端监听
canalClient.run();
}
}
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