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背景

在同步MySQL数据到ES的场景中，挑选了canal组件同步数据。

canal同步MySQL的binlog数据时踩了个大坑

问题描绘

在同步的时分发现canal-adapter中canal-adapter/conf/es7/product.yml 配置文件中sql 句子连表查询的时分会呈现无法更新Elasticsearch 中数据的情况，并且日志没有提示反常（idea启动的时分有错误日志），令人百思不得其解。

问题分析

初步估计是内部解析yml的时分出错了，但详细是什么原因只能看源码调试了。

下载源码

GitHub地址

IDEA导入代码

项目结构图如下：

canal同步MySQL的binlog数据时踩了个大坑
配置文件： application.yml （## 补白代表需求留意和修改的当地）

server:
  port: 8081
spring:
  jackson:
    date-format: yyyy-MM-dd HH:mm:ss
    time-zone: GMT+8
    default-property-inclusion: non_null
canal.conf:
  ## 模式
  mode: kafka #tcp kafka rocketMQ rabbitMQ
  flatMessage: true
  zookeeperHosts:
  syncBatchSize: 1000
  retries: 0
  timeout:
  accessKey:
  secretKey:
  consumerProperties:
    # canal tcp consumer
    canal.tcp.server.host: 127.0.0.1:11111
    canal.tcp.zookeeper.hosts:
    canal.tcp.batch.size: 500
    canal.tcp.username:
    canal.tcp.password:
    # kafka consumer
    ## kafka地址，ip用内网(容器）ip
    kafka.bootstrap.servers: 192.168.0.107:9092
    kafka.enable.auto.commit: false
    kafka.auto.commit.interval.ms: 1000
    kafka.auto.offset.reset: latest
    kafka.request.timeout.ms: 40000
    kafka.session.timeout.ms: 30000
    kafka.isolation.level: read_committed
    kafka.max.poll.records: 1000
    # rocketMQ consumer
    rocketmq.namespace:
    rocketmq.namesrv.addr: 127.0.0.1:9876
    rocketmq.batch.size: 1000
    rocketmq.enable.message.trace: false
    rocketmq.customized.trace.topic:
    rocketmq.access.channel:
    rocketmq.subscribe.filter:
    # rabbitMQ consumer
    rabbitmq.host:
    rabbitmq.virtual.host:
    rabbitmq.username:
    rabbitmq.password:
    rabbitmq.resource.ownerId:
  ## 数据库配置
  srcDataSources:
    defaultDS:
      url: jdbc:mysql://192.168.0.107:3306/test?useUnicode=true
      username: root
      password: root
  canalAdapters:
  ## Kafka主题名
  - instance: canal_manager # canal instance Name or mq topic name
    groups:
    - groupId: g1
      outerAdapters:
      - name: logger
#      - name: rdb
#        key: mysql1
#        properties:
#          jdbc.driverClassName: com.mysql.jdbc.Driver
#          jdbc.url: jdbc:mysql://127.0.0.1:3306/mytest2?useUnicode=true
#          jdbc.username: root
#          jdbc.password: 121212
#      - name: rdb
#        key: oracle1
#        properties:
#          jdbc.driverClassName: oracle.jdbc.OracleDriver
#          jdbc.url: jdbc:oracle:thin:@localhost:49161:XE
#          jdbc.username: mytest
#          jdbc.password: m121212
#      - name: rdb
#        key: postgres1
#        properties:
#          jdbc.driverClassName: org.postgresql.Driver
#          jdbc.url: jdbc:postgresql://localhost:5432/postgres
#          jdbc.username: postgres
#          jdbc.password: 121212
#          threads: 1
#          commitSize: 3000
#      - name: hbase
#        properties:
#          hbase.zookeeper.quorum: 127.0.0.1
#          hbase.zookeeper.property.clientPort: 2181
#          zookeeper.znode.parent: /hbase
	  ## Elasticsearch 配置，canal 1.5后name：es7（用es可能会有问题）
      - name: es7
        hosts: http://192.168.0.107:9200 # 127.0.0.1:9200 for rest mode
        properties:
          ## 模式rest
          mode: rest # or rest
          # security.auth: test:123456 #  only used for rest mode
          cluster.name: elasticsearch
#        - name: kudu
#          key: kudu
#          properties:
#            kudu.master.address: 127.0.0.1 # ',' split multi address

customer.ym （## 补白代表需求留意和修改的当地）

dataSourceKey: defaultDS
## Kafka主题
destination: canal_manager
groupId: g1
esMapping:
  ## Elasticsearch 索引
  _index: product
  ## 主键
  _id: _id
  _type: _doc
  upsert: true
  #  relations:
  #    customer_order:
  #      name: customer
  ## 正确的sql
  #sql: "SELECT s.Sales_No _id, s.Sales_Name salesName, r.Pro_No proNo, p.Pro_Type proType FROM p_sales s INNER JOIN p_salespro_rela r ON r.Sales_No = s.Sales_No LEFT JOIN p_pro_info p ON r.Pro_No = p.Pro_No"
  ## 出错的sql
  sql: "SELECT s.Sales_No _id, s.Sales_Name salesName, p.Pro_Type proType FROM p_sales s INNER JOIN p_salespro_rela r ON r.Sales_No = s.Sales_No LEFT JOIN p_pro_info p ON r.Pro_No = p.Pro_No"
  etlCondition: "where p.c_time>={}"
  commitBatch: 3000

启动进口：CanalAdapterApplication 全量同步接口类：CommonRest 恳求示例：

// post
http://127.0.0.1:8081/etl/es7/customer.yml

查找问题

启动程序后，发现打印了错误日志。

2022-03-18 09:10:56.537 [main] INFO  c.a.o.canal.adapter.launcher.loader.CanalAdapterLoader - Load canal adapter: logger succeed
2022-03-18 09:10:56.742 [main] INFO  c.a.o.c.client.adapter.es.core.config.ESSyncConfigLoader - ## Start loading es mapping config ... 
2022-03-18 09:10:56.874 [main] INFO  c.a.o.c.client.adapter.es.core.config.ESSyncConfigLoader - ## ES mapping config loaded
2022-03-18 09:11:00.028 [main] ERROR c.a.o.canal.adapter.launcher.loader.CanalAdapterLoader - Load canal adapter: es7 failed
java.lang.RuntimeException: java.lang.RuntimeException: com.alibaba.druid.sql.parser.ParserException
	at com.alibaba.otter.canal.client.adapter.es7x.ES7xAdapter.init(ES7xAdapter.java:54) ~[client-adapter.es7x-1.1.5-jar-with-dependencies.jar:na]
	at com.alibaba.otter.canal.adapter.launcher.loader.CanalAdapterLoader.loadAdapter(CanalAdapterLoader.java:225) [classes/:na]
	at com.alibaba.otter.canal.adapter.launcher.loader.CanalAdapterLoader.init(CanalAdapterLoader.java:56) [classes/:na]
	at com.alibaba.otter.canal.adapter.launcher.loader.CanalAdapterService.init(CanalAdapterService.java:60) [classes/:na]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_271]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_271]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_271]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_271]
	at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleElement.invoke(InitDestroyAnnotationBeanPostProcessor.java:365) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleMetadata.invokeInitMethods(InitDestroyAnnotationBeanPostProcessor.java:308) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeInitialization(InitDestroyAnnotationBeanPostProcessor.java:135) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsBeforeInitialization(AbstractAutowireCapableBeanFactory.java:422) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1694) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:579) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:501) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$1(AbstractBeanFactory.java:353) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.cloud.context.scope.GenericScope$BeanLifecycleWrapper.getBean(GenericScope.java:390) ~[spring-cloud-context-2.0.0.RELEASE.jar:2.0.0.RELEASE]
	at org.springframework.cloud.context.scope.GenericScope.get(GenericScope.java:184) ~[spring-cloud-context-2.0.0.RELEASE.jar:2.0.0.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:350) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1089) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.cloud.context.scope.refresh.RefreshScope.eagerlyInitialize(RefreshScope.java:126) ~[spring-cloud-context-2.0.0.RELEASE.jar:2.0.0.RELEASE]
	at org.springframework.cloud.context.scope.refresh.RefreshScope.start(RefreshScope.java:117) ~[spring-cloud-context-2.0.0.RELEASE.jar:2.0.0.RELEASE]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_271]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_271]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_271]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_271]
	at org.springframework.context.event.ApplicationListenerMethodAdapter.doInvoke(ApplicationListenerMethodAdapter.java:264) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.event.ApplicationListenerMethodAdapter.processEvent(ApplicationListenerMethodAdapter.java:182) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.event.ApplicationListenerMethodAdapter.onApplicationEvent(ApplicationListenerMethodAdapter.java:144) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:400) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:354) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:888) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.finishRefresh(ServletWebServerApplicationContext.java:161) ~[spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.__refresh(AbstractApplicationContext.java:553) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.jrLockAndRefresh(AbstractApplicationContext.java:40002) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:41008) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) ~[spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:395) ~[spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:327) ~[spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
	at com.alibaba.otter.canal.adapter.launcher.CanalAdapterApplication.main(CanalAdapterApplication.java:19) ~[classes/:na]
Caused by: java.lang.RuntimeException: com.alibaba.druid.sql.parser.ParserException
	at com.alibaba.otter.canal.client.adapter.es.core.ESAdapter.init(ESAdapter.java:83) ~[client-adapter.es7x-1.1.5-jar-with-dependencies.jar:na]
	at com.alibaba.otter.canal.client.adapter.es7x.ES7xAdapter.init(ES7xAdapter.java:52) ~[client-adapter.es7x-1.1.5-jar-with-dependencies.jar:na]
	... 44 common frames omitted
Caused by: com.alibaba.druid.sql.parser.ParserException: null
	at com.alibaba.otter.canal.client.adapter.es.core.config.SqlParser.parse(SqlParser.java:71) ~[client-adapter.es7x-1.1.5-jar-with-dependencies.jar:na]
	at com.alibaba.otter.canal.client.adapter.es.core.ESAdapter.addSyncConfigToCache(ESAdapter.java:143) ~[client-adapter.es7x-1.1.5-jar-with-dependencies.jar:na]
	at com.alibaba.otter.canal.client.adapter.es.core.ESAdapter.init(ESAdapter.java:75) ~[client-adapter.es7x-1.1.5-jar-with-dependencies.jar:na]
	... 45 common frames omitted
2022-03-18 09:11:00.046 [main] INFO  c.alibaba.otter.canal.connector.core.spi.ExtensionLoader - extension classpath dir: /Users/Desktop/workspace/canal-canal-1.1.5/client-adapter/launcher/target/canal-adapter/plugin
2022-03-18 09:11:00.101 [main] INFO  c.a.o.canal.adapter.launcher.loader.CanalAdapterLoader - Start adapter for canal-client mq topic: canal_manager-g1 succeed
2022-03-18 09:11:00.101 [Thread-35] INFO  c.a.otter.canal.adapter.launcher.loader.AdapterProcessor - =============> Start to connect destination: canal_manager <=============
2022-03-18 09:11:00.101 [main] INFO  c.a.o.canal.adapter.launcher.loader.CanalAdapterService - ## the canal client adapters are running now ......
2022-03-18 09:11:00.113 [main] INFO  org.apache.coyote.http11.Http11NioProtocol - Starting ProtocolHandler ["http-nio-8081"]
2022-03-18 09:11:00.126 [main] INFO  org.apache.tomcat.util.net.NioSelectorPool - Using a shared selector for servlet write/read
2022-03-18 09:11:00.128 [Thread-35] INFO  o

检查日志反常好像是sql解析反常：java.lang.RuntimeException: com.alibaba.druid.sql.parser.ParserException，可是sql放到Navicat或其他工具中都能够正常履行，可能是canal内部有自己的解析规则。

依据错误日志断点调试一下，发现详细的问题在ES7xAdapter 适配器初始化的时分出错了。反常信息：“联系条件”列有必要位于“挑选”列中（Relation condition column must in select columns.）。

canal同步MySQL的binlog数据时踩了个大坑

// ES同步指定sql格式解析 SqlParser.java

/**
     * 解析sql
     *
     * @param sql sql
     * @return 视图目标
     */
    public static SchemaItem parse(String sql) {
        try {
            SQLStatementParser parser = new MySqlStatementParser(sql);
            SQLSelectStatement statement = (SQLSelectStatement) parser.parseStatement();
            MySqlSelectQueryBlock sqlSelectQueryBlock = (MySqlSelectQueryBlock) statement.getSelect().getQuery();
            SchemaItem schemaItem = new SchemaItem();
            schemaItem.setSql(SQLUtils.toMySqlString(sqlSelectQueryBlock));
            SQLTableSource sqlTableSource = sqlSelectQueryBlock.getFrom();
            List<TableItem> tableItems = new ArrayList<>();
            SqlParser.visitSelectTable(schemaItem, sqlTableSource, tableItems, null);
            tableItems.forEach(tableItem -> schemaItem.getAliasTableItems().put(tableItem.getAlias(), tableItem));
            List<FieldItem> fieldItems = collectSelectQueryFields(sqlSelectQueryBlock);
            fieldItems.forEach(fieldItem -> schemaItem.getSelectFields().put(fieldItem.getFieldName(), fieldItem));
            schemaItem.init();
            if (schemaItem.getAliasTableItems().isEmpty() || schemaItem.getSelectFields().isEmpty()) {
                throw new ParserException("Parse sql error");
            }
            return schemaItem;
        } catch (Exception e) {
            throw new ParserException();
        }
    }

解决方案

依据反常提示和测试，咱们知道canal的配置文件sql格式要求连表查询的时分，有必要将相关条件也查出来，就是说假如表A和表B的相关字段都要查出来。

// 正确的sql，要将相关的两个表主键都查出来
select a.id, b.id from a INNER JOIN a.id = c.a_id LEFT JOIN c.b_id = b.id
// 错误的sql
select a.id from a INNER JOIN a.id = c.a_id LEFT JOIN c.b_id = b.id

总结

有些问题仍是需求源码才干发现的，就像这个情况，日志只提示了sql解析反常，可是看起来又没有问题，只能去看代码逻辑调试，才干发现底子的原因。个人经验总结，假如有不对的当地，请大家纠正。