devrish / spring-boot-demo Goto Github PK

To start all required services:

docker compose up --build -d

Next, get into server container and start the server:

docker exec -it demo-demo-1 /bin/sh

cd /app

# Optional step if permission geting denied
# chmod 777 buildNrun.sh

./buildNrun.sh

After that, write code in the local vs code itself; changes will automatically reflect in container as volume was mounted in docker-compose. After making necessary changes, again run the buildNrun.sh script, and so on...

Note: server could also have been started from dockerfile itself by doing CMD ["sh","/app/buildNrn.sh"], but the issue with that is the restarting of server after making changes. nodemon like strategy doesn't suit well with java, as we need to both build and run. Starting a build after every minor change is not efficient. So rather, get into the container terminal and build and run.

• To expose a docker container port to host, we need to add ports: 5430:5432 to docker-compose file
  • Note that the proper order is < host-port >:< container-port >
  • So after this, we can access the container's psql process through our local machine's 5430 port. Try it out: psql -h localhost -p 5430 -U docker
• To expose all host ports to docker container, we need to add extra_hosts: host.docker.internal:host-gateway to docker-compose file
  • So after this, if any process tries to access host.docker.internal:xxxx then it would originally be accessing localhost:xxxx of the host machine
  • So, I had to add the jdbc address as jdbc:postgresql://host.docker.internal:5430/student in application.properties file

So, the docker container of server is accessing host.docker.internal:5430 which gets redirected to localhost:5430 of local machine which again gets redirected to localhost:5432 of postgres container (due to port exposing done for postgres container); and thus finally its able to access the database.