chore: add devcontainer support

Author: filipowm

.devcontainer/Dockerfile

@@ -0,0 +1,17 @@
+FROM mcr.microsoft.com/devcontainers/java:0-11
+
+ARG INSTALL_MAVEN="false"
+ARG MAVEN_VERSION=""
+
+ARG INSTALL_GRADLE="true"
+ARG GRADLE_VERSION=""
+
+RUN if [ "${INSTALL_MAVEN}" = "true" ]; then su vscode -c "umask 0002 && . /usr/local/sdkman/bin/sdkman-init.sh && sdk install maven \"${MAVEN_VERSION}\""; fi \
+    && if [ "${INSTALL_GRADLE}" = "true" ]; then su vscode -c "umask 0002 && . /usr/local/sdkman/bin/sdkman-init.sh && sdk install gradle \"${GRADLE_VERSION}\""; fi
+
+# [Optional] Uncomment this section to install additional OS packages.
+# RUN apt-get update && export DEBIAN_FRONTEND=noninteractive \
+#     && apt-get -y install --no-install-recommends <your-package-list-here>
+
+# [Optional] Uncomment this line to install global node packages.
+# RUN su vscode -c "source /usr/local/share/nvm/nvm.sh && npm install -g <your-package-here>" 2>&1

.devcontainer/devcontainer.json

@@ -0,0 +1,24 @@
+// For format details, see https://aka.ms/devcontainer.json. For config options, see the
+// README at: https://github.com/devcontainers/templates/tree/main/src/java-postgres
+{
+	"name": "Java & PostgreSQL",
+	"dockerComposeFile": "docker-compose.yml",
+	"service": "app",
+	"workspaceFolder": "/workspaces/${localWorkspaceFolderBasename}"
+
+	// Features to add to the dev container. More info: https://containers.dev/features.
+	// "features": {}
+
+	// Use 'forwardPorts' to make a list of ports inside the container available locally.
+	// This can be used to network with other containers or with the host.
+	// "forwardPorts": [5432],
+
+	// Use 'postCreateCommand' to run commands after the container is created.
+	// "postCreateCommand": "java -version",
+
+	// Configure tool-specific properties.
+	// "customizations": {},
+
+	// Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root.
+	// "remoteUser": "root"
+}

.devcontainer/docker-compose.yml

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+version: '3.8'
+
+volumes:
+  postgres-data:
+
+services:
+  app:
+    container_name: javadev
+    build: 
+      context: .
+      dockerfile: Dockerfile
+    environment:
+      # NOTE: POSTGRES_DB/USER/PASSWORD should match values in db container
+        POSTGRES_PASSWORD: postgres
+        POSTGRES_USER: postgres
+        POSTGRES_DB: postgres
+        POSTGRES_HOSTNAME: postgresdb
+
+    volumes:
+      - ../..:/workspaces:cached
+      
+    # Overrides default command so things don't shut down after the process ends.
+    command: sleep infinity
+
+    # Runs app on the same network as the database container, allows "forwardPorts" in devcontainer.json function.
+    network_mode: service:db
+
+    # Use "forwardPorts" in **devcontainer.json** to forward an app port locally. 
+    # (Adding the "ports" property to this file will not forward from a Codespace.)
+
+  db:
+    container_name: postgresdb
+    image: postgres:latest
+    restart: unless-stopped
+    volumes:
+      - postgres-data:/var/lib/postgresql/data
+    environment:
+      # NOTE: POSTGRES_DB/USER/PASSWORD should match values in app container
+      POSTGRES_PASSWORD: postgres
+      POSTGRES_USER: postgres
+      POSTGRES_DB: postgres
+
+    # Add "forwardPorts": ["5432"] to **devcontainer.json** to forward PostgreSQL locally.
+    # (Adding the "ports" property to this file will not forward from a Codespace.)