Spring Boot MySQL Example

• Setting up the dev, and production envs for a springboot stack (springboot, and mysql).
• Setting up the dev env using docker, docker volumes, and docker-compose.
• Setting up the prod env using k8s, and persisting the data using persistent volumes on k8s (tested in minikube).
• Source repo for the springboot app

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TOC

1. Deploy using docker and docker-compose
2. Deploy in Kuberentes
3. Errors and troubleshooting
4. Improvements
5. Resources
6. LICENSE

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Deploy locally using Docker

1. Create .env file with the below content for storing the db credentials

   MYSQL_DB_HOST=db  #mysqldb service name
   MYSQL_DB_PORT=3306 #default port for mysql
   MYSQL_DB_USERNAME= #your username
   MYSQL_DB_PASSWORD= #your password
   MYSQL_DB_DNAME=springbootdb #your default database name
   

2. run the below command for starting both the database and the spring-boot service

   docker-compose up --build .
   

3. Tag your docker image and push it to dockerhub

   docker build -t image_name your_username/image_name:version
   

   docker push your_username/image_name:version
   

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Deploy on k8s tested in minikube

1. Create mysql-secret.yaml for storing your db credentials

   To put any values in a Secret file in kuberntes it needs to be base64 encoded

   echo -n your_lovely_name | base64
   echo -n your_strong_complicated_password | base64
   

   mysql-secret.yaml file

   apiVersion: v1
   kind: Secret
   metadata:
     name: mysql-secret
   data:
     MYSQL_DB_USERNAME: #your_lovely encode username
     MYSQL_DB_PASSWORD: #your_strong and complicated pass 
   

   Connect to mysql pod

   exec -it pod/mysql-depl-57969854d7-fqc8h -- /bin/bash
   mysql -u root -p # enter your pw in the prompt
   

2. Run the files:

   kubectl apply -f mysql-configmap.yml && kubectl apply -f mysql-secrets.yml
   

   kubectl apply -f mysql-pvm-pvmc.yml
   

   kubectl apply -f mysql-deployment.yml
   

   kubectl apply -f mysql-service.yml
   

   kubectl apply -f springboot-depl.yml
   

   kubectl apply -f mysql-service.yml
   

   kubectl apply -f springboot-depl.yml
   

   kubectl apply -f springboot-service.yml
   

3. Get the port to accesss your springboot app

   minikube service --url springboot-srv
   

4. Commands for debugging:

   check logs of a deployment

   kubectl logs -f pod/springboot-depl-
   

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Errors and troubleshooting

1. Debendancies in the pom.xml file specfically
   • Updating the springboot version to 2.1.6.RELEASE
   • Adding the maven-surefire-plugin
2. If your mysql pod doesn't start prompting this error mysql: [ERROR] unknown option '--"'
   • This means you have problem with the encoding you shall use an encoding website instead of the echo command

Improvements

• Try to enable hot reload for the local dev environment
  • Search for a way that enables you to hot reload in springboot (e.g flask server in python)
  • Mount the source dir to the docker image
• putting an ingress intop of the service

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Resources

• The option -DskipTests for skipping the unit tests from the build process Resource
• Enable cashing for mvn
• How to create secrets for kuberntes
• ConfigMaps from k8s official docs
• Why data in secrets is base64 encoded
• Creating a mysql volume and volume claim
• Deploying a fullstack mysql+springboot+react using k8s
• How to use mysql with github actions

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LICENSE