我正在遵循this tutorial来使用docker-compose设置spring boot项目。这是我所做的：
我的application.properties：
spring.datasource.url = jdbc:mysql://mysql-demo-container:3306/demo_db?useSSL=false
spring.datasource.username = root
spring.datasource.password =root
spring.datasource.tomcat.testWhileIdle = true
spring.datasource.tomcat.timeBetweenEvictionRunsMillis = 60000
spring.datasource.tomcat.validationQuery = SELECT 1
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect
# Hibernate ddl auto (create, create-drop, validate, update)
spring.jpa.hibernate.ddl-auto = update
我的Dockerfile：
`FROM java:8
LABEL maintainer=“foo.bar@gmail.com”
VOLUME /tmp
EXPOSE 8080
ADD target/spring-boot-data-jpa-example-0.0.1-SNAPSHOT.jar spring-boot-data-jpa-example-0.0.1-SNAPSHOT.jar
ENTRYPOINT ["java","-jar","spring-boot-data-jpa-example-0.0.1-SNAPSHOT.jar"]`
我有这个docker-compose.yml：
version: '3'
services:
mysql-demo-container:
image: mysql:latest
environment:
- MYSQL_ROOT_PASSWORD=root
- MYSQL_DATABASE=demo_db
- MYSQL_PASSWORD=myPass
ports:
- 2012:3306
volumes:
- /data/mysql
spring-boot-jpa-app:
image: spring-boot-jpa-image
build:
context: ./
dockerfile: Dockerfile
depends_on:
- mysql-demo-container
ports:
- 8087:8080
volumes:
- /data/spring-boot-app
我首先mvn clean install生成项目jar文件，然后运行docker-compose up生成映像并希望运行容器。
日志：
$ docker-compose up
Creating network "spring-boot-data-jpa-example-master_default" with the default driver
Creating spring-boot-data-jpa-example-master_mysql-demo-container_1 ... done
Creating spring-boot-data-jpa-example-master_spring-boot-jpa-app_1 ... done
Attaching to spring-boot-data-jpa-example-master_mysql-demo-container_1, spring-boot-data-jpa-example-master_spring-boot-jpa-app_1
mysql-demo-container_1 | Initializing database
mysql-demo-container_1 | 2019-07-02T13:03:05.097872Z 0 [Warning] [MY-011070] [Server] 'Disabling symbolic links using --skip-symbolic-links (or equivalent) is the default. Consider not using this option as it' is deprecated and will be removed in a future release.
mysql-demo-container_1 | 2019-07-02T13:03:05.098037Z 0 [System] [MY-013169] [Server] /usr/sbin/mysqld (mysqld 8.0.16) initializing of server in progress as process 29
mysql-demo-container_1 | 2019-07-02T13:03:09.171833Z 5 [Warning] [MY-010453] [Server] root@localhost is created with an empty password ! Please consider switching off the --initialize-insecure option.
spring-boot-jpa-app_1 |
spring-boot-jpa-app_1 | . ____ _ __ _ _
spring-boot-jpa-app_1 | /\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
spring-boot-jpa-app_1 | ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
spring-boot-jpa-app_1 | \\/ ___)| |_)| | | | | || (_| | ) ) ) )
spring-boot-jpa-app_1 | ' |____| .__|_| |_|_| |_\__, | / / / /
spring-boot-jpa-app_1 | =========|_|==============|___/=/_/_/_/
spring-boot-jpa-app_1 | :: Spring Boot :: (v1.5.9.RELEASE)
spring-boot-jpa-app_1 |
spring-boot-jpa-app_1 | 2019-07-02 13:03:11.516 INFO 1 --- [ main] .s.e.SpringBootDataJpaExampleApplication : Starting SpringBootDataJpaExampleApplication v0.0.1-SNAPSHOT on 3c0d94b76fd6 with PID 1 (/spring-boot-data-jpa-example-0.0.1-SNAPSHOT.jar started by root in /)
spring-boot-jpa-app_1 | 2019-07-02 13:03:11.556 INFO 1 --- [ main] .s.e.SpringBootDataJpaExampleApplication : No active profile set, falling back to default profiles: default
spring-boot-jpa-app_1 | 2019-07-02 13:03:11.979 INFO 1 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@6d5380c2: startup date [Tue Jul 02 13:03:11 UTC 2019]; root of context hierarchy
mysql-demo-container_1 | 2019-07-02T13:03:13.525348Z 0 [System] [MY-013170] [Server] /usr/sbin/mysqld (mysqld 8.0.16) initializing of server has completed
mysql-demo-container_1 | Database initialized
mysql-demo-container_1 | MySQL init process in progress...
mysql-demo-container_1 | MySQL init process in progress...
mysql-demo-container_1 | MySQL init process in progress...
mysql-demo-container_1 | 2019-07-02T13:03:15.636380Z 0 [Warning] [MY-011070] [Server] 'Disabling symbolic links using --skip-symbolic-links (or equivalent) is the default. Consider not using this option as it' is deprecated and will be removed in a future release.
mysql-demo-container_1 | 2019-07-02T13:03:15.636539Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.16) starting as process 80
mysql-demo-container_1 | 2019-07-02T13:03:18.070695Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed.
mysql-demo-container_1 | 2019-07-02T13:03:18.081045Z 0 [Warning] [MY-011810] [Server] Insecure configuration for --pid-file: Location '/var/run/mysqld' in the path is accessible to all OS users. Consider choosing a different directory.
mysql-demo-container_1 | 2019-07-02T13:03:18.152808Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.16' socket: '/var/run/mysqld/mysqld.sock' port: 0 MySQL Community Server - GPL.
mysql-demo-container_1 | 2019-07-02T13:03:18.311442Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Socket: '/var/run/mysqld/mysqlx.sock'
spring-boot-jpa-app_1 | 2019-07-02 13:03:20.039 INFO 1 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
spring-boot-jpa-app_1 | 2019-07-02 13:03:20.221 INFO 1 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
spring-boot-jpa-app_1 | 2019-07-02 13:03:20.232 INFO 1 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.5.23
spring-boot-jpa-app_1 | 2019-07-02 13:03:21.210 INFO 1 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
spring-boot-jpa-app_1 | 2019-07-02 13:03:21.213 INFO 1 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 9251 ms
spring-boot-jpa-app_1 | 2019-07-02 13:03:22.153 INFO 1 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/]
spring-boot-jpa-app_1 | 2019-07-02 13:03:22.169 INFO 1 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
spring-boot-jpa-app_1 | 2019-07-02 13:03:22.178 INFO 1 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
spring-boot-jpa-app_1 | 2019-07-02 13:03:22.178 INFO 1 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]
spring-boot-jpa-app_1 | 2019-07-02 13:03:22.181 INFO 1 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]
mysql-demo-container_1 | Warning: Unable to load '/usr/share/zoneinfo/iso3166.tab' as time zone. Skipping it.
mysql-demo-container_1 | Warning: Unable to load '/usr/share/zoneinfo/leap-seconds.list' as time zone. Skipping it.
spring-boot-jpa-app_1 | 2019-07-02 13:03:25.161 ERROR 1 --- [ main] o.a.tomcat.jdbc.pool.ConnectionPool : Unable to create initial connections of pool.
spring-boot-jpa-app_1 |
spring-boot-jpa-app_1 | com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
spring-boot-jpa-app_1 |
spring-boot-jpa-app_1 | The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
spring-boot-jpa-app_1 | at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_111]
spring-boot-jpa-app_1 | at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_111]
spring-boot-jpa-app_1 | at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_111]
spring-boot-jpa-app_1 | at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_111]
spring-boot-jpa-app_1 | at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) ~[mysql-connector-java-5.1.44.jar!/:5.1.44]
spring-boot-jpa-app_1 | at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:989) ~[mysql-connector-java-5.1.44.jar!/:5.1.44]
spring-boot-jpa-app_1 | at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:341) ~[mysql-connector-java-5.1.44.jar!/:5.1.44]
spring-boot-jpa-app_1 | at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2189) ~[mysql-connector-java-5.1.44.jar!/:5.1.44]
spring-boot-jpa-app_1 | at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2222) ~[mysql-connector-java-5.1.44.jar!/:5.1.44]
spring-boot-jpa-app_1 | at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2017) ~[mysql-connector-java-5.1.44.jar!/:5.1.44]
spring-boot-jpa-app_1 | at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:779) ~[mysql-connector-java-5.1.44.jar!/:5.1.44]
spring-boot-jpa-app_1 | at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) ~[mysql-connector-java-5.1.44.jar!/:5.1.44]
spring-boot-jpa-app_1 | at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_111]
spring-boot-jpa-app_1 | at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_111]
spring-boot-jpa-app_1 | at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_111]
spring-boot-jpa-app_1 | at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_111]
spring-boot-jpa-app_1 | at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) ~[mysql-connector-java-5.1.44.jar!/:5.1.44]
spring-boot-jpa-app_1 | at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:389) ~[mysql-connector-java-5.1.44.jar!/:5.1.44]
spring-boot-jpa-app_1 | at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330) ~[mysql-connector-java-5.1.44.jar!/:5.1.44]
spring-boot-jpa-app_1 | at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:310) ~[tomcat-jdbc-8.5.23.jar!/:na]
spring-boot-jpa-app_1 | at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:203) ~[tomcat-jdbc-8.5.23.jar!/:na]
spring-boot-jpa-app_1 | at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:735) [tomcat-jdbc-8.5.23.jar!/:na]
spring-boot-jpa-app_1 | at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:667) [tomcat-jdbc-8.5.23.jar!/:na]
spring-boot-jpa-app_1 | at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:482) [tomcat-jdbc-8.5.23.jar!/:na]
spring-boot-jpa-app_1 | at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:154) [tomcat-jdbc-8.5.23.jar!/:na]
spring-boot-jpa-app_1 | at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:118) [tomcat-jdbc-8.5.23.jar!/:na]
spring-boot-jpa-app_1 | at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:107) [tomcat-jdbc-8.5.23.jar!/:na]
spring-boot-jpa-app_1 | at org.apache.tomcat.jdbc.pool.DataSourceProxy.getConnection(DataSourceProxy.java:131) [tomcat-jdbc-8.5.23.jar!/:na]
spring-boot-jpa-app_1 | at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111) [spring-jdbc-4.3.13.RELEASE.jar!/:4.3.13.RELEASE]
spring-boot-jpa-app_1 | at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77) [spring-jdbc-4.3.13.RELEASE.jar!/:4.3.13.RELEASE]
spring-boot-jpa-app_1 | at org.springframework.jdbc.support.JdbcUtils.extractDatabaseMetaData(JdbcUtils.java:326) [spring-jdbc-4.3.13.RELEASE.jar!/:4.3.13.RELEASE]
spring-boot-jpa-app_1 | at org.springframework.jdbc.support.JdbcUtils.extractDatabaseMetaData(JdbcUtils.java:366) [spring-jdbc-4.3.13.RELEASE.jar!/:4.3.13.RELEASE]
spring-boot-jpa-app_1 | at org.springframework.boot.autoconfigure.orm.jpa.DatabaseLookup.getDatabase(DatabaseLookup.java:72) [spring-boot-autoconfigure-1.5.9.RELEASE.jar!/:1.5.9.RELEASE]
spring-boot-jpa-app_1 | at org.springframework.boot.autoconfigure.orm.jpa.JpaProperties.determineDatabase(JpaProperties.java:139) [spring-boot-autoconfigure-1.5.9.
从日志开头可以看到，容器似乎已成功创建。
运行docker ps向我显示：
docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
8fa64acb363d mysql:latest "docker-entrypoint.s…" 30 minutes ago Up 30 minutes 33060/tcp, 0.0.0.0:2012->3306/tcp spring-boot-data-jpa-example-master_mysql-demo-container_1
该错误的原因可能是什么？
答案 0 :(得分：1)
您应该意识到reference documentation of Docker Compose中这个非常重要的脚注：
depends_on在启动db之前不等待redis和web处于“就绪”状态-仅在启动之前。如果您需要等待服务准备就绪，请参阅Controlling startup order，以获取有关此问题的更多信息以及解决方案。
对于您而言，您的Spring引导容器将在启动MySQL容器之后立即启动。尽管无法保证MySQL在Spring Boot设置其连接池时将能够建立连接。
这意味着您的Spring引导连接将无法启动，因为MySQL尚未准备好。这将导致您的应用程序容器被杀死。
the documentation I quoted中提到了解决此问题的方法。即，您必须使用某种轮询机制来查看是否可以连接到数据库。
如果您不想使用wait-for-it或wait-for之类的工具，则可以编写一个简单的Shell脚本来执行以下操作：
while ! exec 6<>/dev/tcp/mysql-demo-container/3306; do
echo "Trying to connect to MySQL..."
sleep 10
done
exec java -jar spring-boot-data-jpa-example-0.0.1-SNAPSHOT.jar
这还意味着您必须在ENTRYPOINT中更改Dockerfile才能引用此类Shell脚本，而不是直接运行您的JAR文件。