How to connect to MySQL container on Docker using Spring Boot project-CodePudding

I am trying to run a Spring Boot application where db has to be connected to a MySQL container on Docker. I used following code and commands.

Application properties:

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://mysqldb:3306/practice
spring.datasource.username=root
spring.datasource.password=CVnit1234!
spring.jpa.show-sql=true
spring.sql.init.platform=mysql
spring.sql.init.mode=always
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5Dialect
spring.jpa.hibernate.ddl-auto=update

Commands used for creating container & running it on Docker:

Pulling mysql image from Docker Hub:

docker pull mysql

Creating a container:

docker run --name mysqldb --network spring-net -p 3307:3306 -e MYSQL_ROOT_PASSWORD=password MYSQL_DATABASE=practice -d mysql:latest

After this command, a container is created and even it is up and working fine. I was able to login to sql bash and execute some queries.

I tried with multiple jdbc urls:

jdbc:mysql://mysqldb:3306/practice
jdbc:mysql://mysqldb:3307/practice
jdbc:mysql://mysqldb/practice
jdbc:mysql://host.docker.internal:3306/practice
jdbc:mysql://host.docker.internal:3307/practice

None of this worked, but I was able to connect to localhost:3306 and localhost:3307.

Below is my spring boot code. When I am trying to connect through the Spring Boot application, I was getting the following error.

com.mysql.cj.jdbc.exceptions.CommunicationsException:Communication link failure

The problem over here is when I am trying to connect to localhost the application is up and working, but when trying to connect to mysql container, I was not able to connect.

CodePudding user response：

Check your network to ensure that the application network is connected to the MySQL network

CodePudding user response：

The problem was resolved by changing the port to 6033 and the host to 'localhost.' then you able to login to the MySQL server using the account 'root':

spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://localhost:6033/app_db?allowPublicKeyRetrieval=true&useSSL=false
spring.datasource.username=root
spring.datasource.password=your_pass