docker部署springboot项目，并访问docker中部署的mysql与mongdoDB

解决的问题

1. docker中的springboot项目访问docker中的mysql和mongo

2. MongoDB连接报错

   org.springframework.data.mongodb.UncategorizedMongoDbException: Exception authenticating MongoCredential{mechanism=SCRAM-SHA-256, userName='admin', source='pet', password=, mechanismProperties=}; nested exception is com.mongodb.MongoSecurityException: Exception authenticating MongoCredential{mechanism=SCRAM-SHA-256, userName='admin', source='pet', password=, mechanismProperties=}
    at com.zxmt.app.AppApplicationTests.contextLoads(AppApplicationTests.java:72)
   Caused by: com.mongodb.MongoSecurityException: Exception authenticating MongoCredential{mechanism=SCRAM-SHA-256, userName='admin', source='pet', password=, mechanismProperties=}
    at com.zxmt.app.AppApplicationTests.contextLoads(AppApplicationTests.java:72)
   Caused by: java.lang.IllegalArgumentException: Prohibited character at position 0
    at com.zxmt.app.AppApplicationTests.contextLoads(AppApplicationTests.java:72)
   

3. 跳过SpringBoot打包测试

先看一下最开始的配置

• application.yml

  spring:
    datasource:
      url: jdbc:mysql://localhost:3306/pet?useUnicode=true&characterEncoding=UTF-8&autoReconnect=true&failOverReadOnly=false
      driver-class-name: com.mysql.cj.jdbc.Driver
      username: root
      password: 123456
    data:
      mongodb:
        host: localhost
        port: 27017
        username: admin
        password: 123456
        database: pet
  

• docker 安装mysql与mongo

将项目打包成为jar包，并上传到服务器

​ 打包的时候，项目会进行测试，然后会出现一个问题。就是mongodb连接报错，这个问题是由于我们使用分开写配置文件，host,port,database这种造成的，具体原因我也不太清楚，有人说是jdk版本问题，所以直接换成uri模式

org.springframework.data.mongodb.UncategorizedMongoDbException: Exception authenticating MongoCredential{mechanism=SCRAM-SHA-256, userName='admin', source='pet', password=, mechanismProperties=}; nested exception is com.mongodb.MongoSecurityException: Exception authenticating MongoCredential{mechanism=SCRAM-SHA-256, userName='admin', source='pet', password=, mechanismProperties=}
    at com.zxmt.app.AppApplicationTests.contextLoads(AppApplicationTests.java:72)
Caused by: com.mongodb.MongoSecurityException: Exception authenticating MongoCredential{mechanism=SCRAM-SHA-256, userName='admin', source='pet', password=, mechanismProperties=}
    at com.zxmt.app.AppApplicationTests.contextLoads(AppApplicationTests.java:72)
Caused by: java.lang.IllegalArgumentException: Prohibited character at position 0
    at com.zxmt.app.AppApplicationTests.contextLoads(AppApplicationTests.java:72)

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/pet?useUnicode=true&characterEncoding=UTF-8&autoReconnect=true&failOverReadOnly=false
    driver-class-name: com.mysql.cj.jdbc.Driver
    username: root
    password: 123456
  data:
    mongodb:
    # 重点:mongodb://用户名:密码@localhost:27017/数据库名
      uri: mongodb://admin:123456@localhost:27017/pet

image.png

在jar文件同级目录新建Dockerfile，内容如下

FROM java:8-alpine
ADD app-0.0.1-SNAPSHOT.jar app.jar
EXPOSE 8080
ENTRYPOINT ["java","-jar","/app.jar"]

然后在当前目录执行(最后有一个点,表示上下文 )：docker build -t pet-app .

因为docker中运行着mysql和mongo，所以我们直接开始运行pet-app这个自己打包的镜像

dokcer run -d -p 8080:8080 --name pet-app pet-app

-d 表示后台运行, --name 表示取一个别名 ,最后一个pet-app表示刚才的镜像名称

OK问题来了

你以为一切很顺利，但是你访问接口会发现错误

Error querying database.  Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is java.sql.SQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up.\n### The error may exist in com/zxmt/app/mapper/AgreementMapper.java (best guess)\n### The error may involve com.zxmt.app.mapper.AgreementMapper.selectById\n### The error occurred while executing a query\n### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is java.sql.SQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up."

这个问题就是，docker中的springboot没能通过localhost:3306访问到数据库，同时mongo也是访问不到

解决方案1：直接将localhost改为服务器地址就可以了，相当于docker中的服务通过网络访问服务器端口，服务器再访问docker。(⊙o⊙)…这个决绝办法有点low

解决方案2:使用docker中的--link参数

1. 先修改配置文件。将原来的主机地址都取一个别名例如下面的mysql,mongo

   spring:
     datasource:
       url: jdbc:mysql://mysql:3306/pet?useUnicode=true&characterEncoding=UTF-8&autoReconnect=true&failOverReadOnly=false
       driver-class-name: com.mysql.cj.jdbc.Driver
       username: root
       password: 123456
     data:
       mongodb:
         uri: mongodb://admin:123456@mongo:27017/pet
   

2. 因为改了这个配置文件，打包的时候会进行测试，(你想你都写成jdbc:mysql://mysql:3306这样了，测试能通过吗)所以现在需要配置跳过测试(在pom的properties中加代码)

   
          true
   
   

3. 还是Dockerfile打包成镜像

4. 最后是通过镜像启动容器的代码!!!!重点

   docker run -p 8080:8080 -d --link=mysql:mysql --link=mongo:mongo  --name pet-app  pet-app
   

   --link:前面的mysql表示启动的容器的名称，后面是别名名称对应上面的配置文件中的mysql

   jdbc:mysql://mysql:3306/pet?useUnicode=true&characterEncoding=UTF-8&autoReconnect=true&failOverReadOnly=false

   当然mongo也是一样。。

   再把之前的错误启动方式贴一次对比一下

   # 错误的
   dokcer run -d -p 8080:8080 --name pet-app pet-app
   #正确的
   docker run -p 8080:8080 -d --link=mysql:mysql --link=mongo:mongo  --name pet-app  pet-app