Nacos 连接 Mysql 时因为时区问题无法连接。

[程思远]

操作系统：CentOS 7.6 64bit
Nacos 报错信息：
Caused by: com.alibaba.nacos.api.exception.NacosException: Nacos Server did not start because dumpservice bean construction failure : No DataSource set at com.alibaba.nacos.config.server.service.dump.DumpService.dumpOperate(DumpService.java:203) at com.alibaba.nacos.config.server.service.dump.ExternalDumpService.init(ExternalDumpService.java:50) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleElement.invoke(InitDestroyAnnotationBeanPostProcessor.java:363) at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleMetadata.invokeInitMethods(InitDestroyAnnotationBeanPostProcessor.java:307) at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeInitialization(InitDestroyAnnotationBeanPostProcessor.java:136) ... 40 common frames omitted Caused by: java.lang.IllegalStateException: No DataSource set at org.springframework.util.Assert.state(Assert.java:73) at org.springframework.jdbc.support.JdbcAccessor.obtainDataSource(JdbcAccessor.java:77) at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:371) at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:452) at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:462) at org.springframework.jdbc.core.JdbcTemplate.queryForObject(JdbcTemplate.java:473) at org.springframework.jdbc.core.JdbcTemplate.queryForObject(JdbcTemplate.java:480) at com.alibaba.nacos.config.server.service.repository.extrnal.ExternalStoragePersistServiceImpl.findConfigMaxId(ExternalStoragePersistServiceImpl.java:553)

[程思远]

这是由于 Mysql 8.0 版本之后连接时需要指定时区信息。
在文件 doc/docker-compose/yaml/nacos/nacos-config.env 中，将 MYSQL_SERVICE_DB_PARAM="characterEncoding=utf8&connectTimeout=1000&socketTimeout=3000&autoReconnect=true&useSSL=false" 改为 MYSQL_SERVICE_DB_PARAM="characterEncoding=utf8&connectTimeout=1000&socketTimeout=3000&autoReconnect=true&useSSL=false&serverTimezone=Asia/Shanghai" 。
然后重启服务，即可解决问题。