docker化 spring-boot 和 mysql 时出错。无法初始化 JPA EntityManagerFactory 无法构建 Hibernate SessionFactory

Question

我正在尝试使用 MySql 对我的 Spring Boot 应用程序进行 dockerize。 执行此操作时出现错误：

> org.hibernate.orm.deprecation            : HHH90000025: MySQLDialect
> does not need to be specified explicitly using 'hibernate.dialect'
> (remove the property setting and it will be selected by default) db-1 
> | 2024-09-19T10:35:56.442175Z 0 [Warning] [MY-013746] [Server] A
> deprecated TLS version TLSv1 is enabled for channel mysql_main db-1  
> | 2024-09-19T10:35:56.442209Z 0 [Warning] [MY-013746] [Server] A
> deprecated TLS version TLSv1.1 is enabled for channel mysql_main db-1 
> | 2024-09-19T10:35:56.730732Z 6 [Warning] [MY-010453] [Server]
> root@localhost is created with an empty password ! Please consider
> switching off the --initialize-insecure option. app-1  |
> 2024-09-19T10:35:57.344Z  INFO 1 --- [dockerFile] [           main]
> o.h.e.t.j.p.i.JtaPlatformInitiator       : HHH000489: No JTA platform
> available (set 'hibernate.transaction.jta.platform' to enable JTA
> platform integration) app-1  | 2024-09-19T10:35:57.382Z  INFO 1 ---
> [dockerFile] [           main] com.zaxxer.hikari.HikariDataSource     
> : HikariPool-1 - Starting... app-1  | 2024-09-19T10:35:58.513Z  WARN 1
> --- [dockerFile] [           main] o.h.engine.jdbc.spi.SqlExceptionHelper   : SQL Error: 0, SQLState:
> 08S01 app-1  | 2024-09-19T10:35:58.514Z ERROR 1 --- [dockerFile] [    
> main] o.h.engine.jdbc.spi.SqlExceptionHelper   :
> 
> 
> ***Communications link failure app-1  |  app-1  | The last packet sent successfully to the server was 0 milliseconds ago. The driver has not
> received any packets from the server. app-1  |
> 2024-09-19T10:35:58.523Z ERROR 1 --- [dockerFile] [           main]
> j.LocalContainerEntityManagerFactoryBean : Failed to initialize JPA
> EntityManagerFactory: [PersistenceUnit: default] Unable to build
> Hibernate SessionFactory; nested exception is
> org.hibernate.exception.JDBCConnectionException: Unable to open JDBC
> Connection for DDL execution [Communications link failure app-1  | 
> app-1  | The last packet sent successfully to the server was 0
> milliseconds ago. The driver has not received any packets from the
> server.] [n/a] app-1  | 2024-09-19T10:35:58.524Z  WARN 1 ---
> [dockerFile] [           main]*** 
> 
> 
> ConfigServletWebServerApplicationContext : Exception encountered
> during context initialization - cancelling refresh attempt:
> org.springframework.beans.factory.BeanCreationException: Error
> creating bean with name 'entityManagerFactory' defined in class path
> resource
> [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaConfiguration.class]:
> [PersistenceUnit: default] Unable to build Hibernate SessionFactory;
> nested exception is org.hibernate.exception.JDBCConnectionException:
> Unable to open JDBC Connection

它在本地主机上工作正常，但在对其进行 docker 化时出现错误。 这是我的应用程序属性：

spring.application.name=dockerFile
spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://localhost:3306/localspringbootdb?createDatabaseIfNotExist=true
spring.datasource.username=root
spring.datasource.password=use1234
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.jpa.properties.hibernate.boot.allow_jdbc_metadata_access=false
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQLDialect

Dockerfile

FROM openjdk:17-alpine
WORKDIR /opt
ENV PORT 8080
EXPOSE 8080
COPY target/*.jar /opt/app.jar
ENTRYPOINT exec java $JAVA_OPTS -jar app.jar

docker-compose.yml

version: '2.29.4'

services:
  app:
    image: javademo
    ports:
      - 8080:8080
    environment:
      SPRING_DATASOURCE_URL: jdbc:mysql://db:3306/localspringbootdb
      SPRING_DATASOURCE_USERNAME: admin
      SPRING_DATASOURCE_PASSWORD: root


    depends_on:
      - db

  db:
    image: mysql:8.0.27
    environment:
      MYSQL_ROOT_PASSWORD: root
      MYSQL_DATABASE: localspringbootdb
      MYSQL_USER: admin
      MYSQL_PASSWORD: root
    ports:
      - 3307:3306

以下是完整的源代码和文件供您参考： https://github.com/KapilKokcha/Dockerized-Spring-Boot-And-Mysql

我尝试从所有这些创建 docker，但失败了并且不知道为什么。

Answer 1

问题是当tomcat尝试连接到mysql服务器时，但它没有完全加载，因此导致连接错误。 为了解决这个问题，我为 mysql 服务器添加了健康检查，现在 tomcat 依赖于健康的数据库容器。

这是更新后的 docker-compose.yml

version: '2.29.4'

services:
  db:
    image: mysql:8.0.27
    environment:
      MYSQL_ROOT_PASSWORD: root
      MYSQL_DATABASE: localspringbootdb
      MYSQL_USER: admin
      MYSQL_PASSWORD: root
    ports:
      - 3307:3306
    healthcheck:
      test: [ "CMD", "mysqladmin", "ping", "-h", "localhost" ]
      interval: 10s
      retries: 5

  app:
    image: javademo
    depends_on:
      db:
        condition: service_healthy
    environment:
      SPRING_DATASOURCE_URL: jdbc:mysql://db:3306/localspringbootdb
      SPRING_DATASOURCE_USERNAME: admin
      SPRING_DATASOURCE_PASSWORD: root
    ports:
      - 8080:8080

我还更新了仓库：https://github.com/KapilKokcha/Dockerized-Spring-Boot-And-Mysql

随时提出任何更改建议或推荐良好实践。