edu-spring-postgres

Spring Boot + Postgres (Docker Compose)

A full JVM application + database stack — no local JDK, no local Postgres, just one command.

Modified from the official spring-postgres example in awesome-compose.

The entire system/stack is defined in compose.yaml.

This sample demonstrates:

• Spring Boot
• PostgreSQL
• Docker Compose
• Container networking
• Persistence wiring (data survives container deletion)

The compose file defines two services: backend and db.

• Port mapping — 8888:8080 maps host port 8888 to container port 8080 (where Spring Boot listens). Visit the app at http://localhost:8888.
• Service discovery — the backend connects to Postgres at hostname db (just the service name). Compose puts both services on the same network and gives each one DNS, so no IPs or links are needed.

Additions by ddfreiling

• Added /new form to add a greeting
• Added /greetings endpoint to show all greetings

Commands

Start the entire stack:

docker compose up --detach --build

Add a greeting via the /new form at http://localhost:8888/new, then peek at the actual table inside the running database container:

docker compose exec db psql -U postgres -d example -c "SELECT * FROM greetings;"

Stop the stack:

docker compose stop

Delete it all (including data volumes):

docker compose down --volumes

Questions

• What happened to the data? Did your greetings survive?

Observations

• Entire system stack defined as code
• One command deployment
• Application + infrastructure integration
• Environment-driven configuration
• No local JDK or database required
• Automatic networking
• Portable infrastructure