Spring Boot 无法与 docker 环境中的 MySQL DB 通信

Question

我正在尝试运行 springboot 微服务 docker 映像。它从配置服务器获取数据库连接属性。但是它无法连接到容器。

错误：

JdbcEnvironmentInitiator - HHH000342: Could not obtain connection to query metadata : Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.

例外：

at com.mysql.cj.jdbc.exceptions.SQLError.createCommunicationsException(SQLError.java:174) ~[mysql-connector-java-8.0.21.jar!/:8.0.21]
Caused by :
at java.net.PlainSocketImpl.socketConnect(Native Method) ~[na:1.8.0_242]
2020-09-28 11:39:32.782 [ : ] WARN  [task-1] o.h.e.j.s.SqlExceptionHelper - SQL Error: 0, SQLState: 08S01
 1 --- [         task-1] o.h.engine.jdbc.spi.SqlExceptionHelper   : SQL Error: 0, SQLState: 08S01
2020-09-28 11:39:32.791 [ : ] ERROR [task-1] o.h.e.j.s.SqlExceptionHelper - Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
 1 --- [         task-1] o.h.engine.jdbc.spi.SqlExceptionHelper   : Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.

位于配置服务器的属性

shopping-service.datasource.url: jdbc:mysql://A.B.C.D:3306/shoppingCartDB
shopping-service.datasource.username: root
shopping-service.datasource.password: root

A.B.C.D 是我的 docker 主机 IP。

application.yaml

datasource:
    url: ${shopping-service.datasource.url}
    username: ${shopping-service.datasource.username}
    password: ${shopping-service.datasource.password}
    #driver-class-name: com.mysql.jdbc.Driver
  jpa:
    generate-ddl: true
    properties:
      hibernate:
        dialect: org.hibernate.dialect.MySQL8Dialect
        show_sql: true
        ddl-auto: create-drop
  profiles:
    active: dev

我已经从 docker hub 拉取了 MySQL 8.0 docker 镜像。

docker pull mysql/mysql-server:8.0
docker run --name=mysql-container -d mysql/mysql-server:8.0

将密码更改为“root”。

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'root';
Query OK, 0 rows affected (0.02 sec)

创建数据库：

mysql> create DATABASE shoppingCartDB;
Query OK, 1 row affected (0.00 sec)

mysql> exit

Docker 运行

docker run -p 5000:5000 shoppingms:latest --env shopping-service.configserverurl=http://A.B.C.D:8888 --env shopping-service.eureka.url=http://A.B.C.D:4444/eureka

它能够从配置服务器获取属性。我检查了日志。错误来自这一行：

 com.zaxxer.hikari.HikariDataSource       : HikariPool-1 - Starting...

在我的本地环境中，我可以使用具有相同连接参数的本地安装的 MySQL Db。但是在docker中我得到了例外。我哪里出错了，谁能帮帮我。

更新：

将 MySQL 容器暴露到 3306 端口后，错误出现在现在：

2020-09-28 12:07:43.942 [ : ] WARN  [task-1] o.h.e.j.e.i.JdbcEnvironmentInitiator - HHH000342: Could not obtain connection to query metadata : null,  message from server: "Host 'Some-IP' is not allowed to connect to this MySQL server"
     1 --- [         task-1] o.h.e.j.e.i.JdbcEnvironmentInitiator     : HHH000342: Could not obtain connection to query metadata : null,  message from server: "Host 'Some-IP' is not allowed to connect to this MySQL server"

2020-09-28 12:07:49.219 [ : ] WARN  [task-1] o.h.e.j.s.SqlExceptionHelper - SQL Error: 1130, SQLState: HY000
 1 --- [         task-1] o.h.engine.jdbc.spi.SqlExceptionHelper   : SQL Error: 1130, SQLState: HY000
2020-09-28 12:07:49.225 [ : ] ERROR [task-1] o.h.e.j.s.SqlExceptionHelper - null,  message from server: "Host 'Some-IP' is not allowed to connect to this MySQL server"
 1 --- [         task-1] o.h.engine.jdbc.spi.SqlExceptionHelper   : null,  message from server: "Host 'Some-IP' is not allowed to connect to this MySQL server"

Answer 1

我建议运行一个 docker compose 文件来描述您的应用程序设置。

作为指导，这是一个用于在给定网络上运行 phpMyAdmin、MySQL 8、tomcat 的 compose 文件。我对您的申请要求进行了猜测：

version: "3.5"
services:
  # Update the below for your application
  app:
    image: shoppingms:latest
    restart: always
    ports:
      - 5000:5000
    links:
      - db:db
    environment: 
      - shopping-service.configserverurl=http://A.B.C.D:8888
      - shopping-service.eureka.url=http://A.B.C.D:4444/eureka
    networks: 
      - appnet
  db:
    image: mysql:8.0
    restart: always
    ports:
        - 3306:3306
    command: --default-authentication-plugin=mysql_native_password
    environment:
        MYSQL_DATABASE: mydb
        MYSQL_USER: user
        MYSQL_PASSWORD: user123
        MYSQL_ROOT_PASSWORD: user123
    volumes:
        - ./sql-init:/docker-entrypoint-initdb.d
        - ./mysql/data:/var/lib/mysql
    networks:
        - appnet
  phpmyadmin:
    image: phpmyadmin/phpmyadmin
    restart: always
    links:
        - db:db
    ports:
        - 8201:80
    environment:
        MYSQL_USER: user
        MYSQL_PASSWORD: user123
        MYSQL_ROOT_PASSWORD: user123
    networks:
        - appnet
  tomcat:
    image: library/tomcat:9
    restart: always
    links:
        - db:db
    ports:
        - 8081:8080
    volumes:
      - ./tomcat/webapps:/usr/local/tomcat/webapps
      - ./tomcat/logs:/usr/local/tomcat/logs
    networks:
        - appnet

networks:
  appnet:
    name: appnet

在这个应用程序中，我正在运行一个外部托管的 tomcat 服务器，并将 Spring webapp 卷入容器中。为了便于外部访问，还暴露了各种端口。

您需要根据您的要求配置/调整您的应用程序容器。

数据库在 DNS 名称 db 上公开，这是 phpMyAdmin 使用的。

Answer 2

现在可以解决问题了。

 1. Identify the ip address from docker inspect command.
 2. Create an user for that ip.
 3. Need to alter the new user password.
 4. Grant some privileges to the user.
 5. Exit

现在再次运行你的容器，这次它可以获得连接并成功创建表。