Merge pull request 'chore(deployment): add deployment for backend' (!16) from deployment/backend into main

Reviewed-on: https://git.simonis.lol/projects/casino/pulls/16
Reviewed-by: jank1619 <jan@kjan.email>
Reviewed-by: Huy <ptran@noreply@simonis.lol>

backend/.docker/Dockerfile

@@ -0,0 +1,20 @@
+FROM gradle:jdk22 AS builder
+WORKDIR /app
+
+COPY gradlew build.gradle.kts settings.gradle.kts ./
+COPY gradle gradle
+
+RUN chmod +x gradlew
+RUN ./gradlew dependencies
+
+COPY src src
+
+RUN ./gradlew clean build -x test
+
+FROM openjdk:22-jdk-slim
+WORKDIR /app
+
+COPY --from=builder /app/build/libs/*.jar app.jar
+
+EXPOSE 8080
+ENTRYPOINT ["java", "-jar", "app.jar"]

backend/.dockerignore

@@ -0,0 +1,2 @@
+.gradle
+build

backend/src/main/resources/application.properties

@@ -1,4 +1,4 @@
-spring.datasource.url=jdbc:postgresql://localhost:5432/postgresdb
+spring.datasource.url=jdbc:postgresql://${DB_HOST:-localhost}:5432/postgresdb
 spring.datasource.username=postgres_user
 spring.datasource.password=postgres_pass
 server.port=8080