update build application guide

Containerfile

@@ -0,0 +1,11 @@
+# Build demoapp-backend using dockerfile-maven-plugin: https://github.com/spotify/dockerfile-maven
+
+ARG RUNTIME_IMAGE="registry.access.redhat.com/ubi8/openjdk-17-runtime"
+FROM ${RUNTIME_IMAGE}
+WORKDIR /app
+
+# Add the service itself
+ARG JAR_FILE
+COPY target/${JAR_FILE} demoapp-backend.jar
+
+CMD ["/usr/bin/java", "-jar", "/app/demoapp-backend.jar"]

Containerfile.multistage

@@ -1,18 +1,19 @@
-# Build demoapp-backend using Multi-Stage Container Build
+# Build demoapp-backend using Multi-Stage Container Build: https://docs.docker.com/build/building/multi-stage/
 
 ARG BUILD_IMAGE="registry.access.redhat.com/ubi8/openjdk-17"
 ARG RUNTIME_IMAGE="registry.access.redhat.com/ubi8/openjdk-17-runtime"
-ARG MAVEN_ARGS="-Dmaven.test.skip=true"
 
 # Build
 FROM ${BUILD_IMAGE} as build
 ARG MAVEN_ARGS
+WORKDIR /build
 
 COPY src ./src
 COPY pom.xml ./pom.xml
-RUN mvn "${MAVEN_ARGS[@]}" clean package
+RUN mvn clean package -Dmaven.test.skip=true -Ddockerfile.skip
 
 # APP
 FROM ${RUNTIME_IMAGE}
-COPY --from=build /home/jboss/target/demoapp-backend*.jar demoapp-backend.jar
-CMD ["/usr/bin/java", "-jar", "demoapp-backend.jar"]
+WORKDIR /app
+COPY --from=build /build/target/demoapp-backend*.jar demoapp-backend.jar
+CMD ["/usr/bin/java", "-jar", "/app/demoapp-backend.jar"]

README.md

@@ -22,7 +22,7 @@ This project uses [Visual Studio Code Dev Containers](https://code.visualstudio.
 
 Visual Studio Code Dev Containers extension looks up [devcontainer.json](.devcontainer/devcontainer.json) file which defines the Container environment specification.
 
-### Build Application JAR
+### Build Application Container Image with Maven
 To ensure successful build of this project, `project.properties['java.version']` value from [pom.xml](pom.xml) must match with `features['ghcr.io/devcontainers/features/java:1'].version` from [devcontainer.json](.devcontainer/devcontainer.json)
 ```xml
 <!-- pom.xml -->
@@ -48,12 +48,14 @@ mvn clean install
 # Build and skip tests
 mvn clean install -Dmaven.test.skip=true
 
-# Note: Visual Studio Dev Container creates and runs `mysql` service. To add other dependency services, update `.devcontainer/compose.yaml`
+# Notes:
+# - Visual Studio Dev Container creates and runs `mysql` service. To add other dependency services, update `.devcontainer/compose.yaml`
+# - Maven was configured to create 2 image tags: [1] based on project.version [2] `latest` tag
 ```
-### Build Application Container with Multi-stage builds
+### Build Application Container Image with Multi-stage builds
 [Multi-stage](https://docs.docker.com/build/building/multi-stage/) builds are useful to anyone who has struggled to optimize Dockerfiles while keeping them easy to read and maintain.
 ```sh
-docker build -f Containerfile.multistage -t demoapp-backend .
+docker build -f Containerfile.multistage -t demoapp-backend:latest .
 ```
 
 ## Run Application from Visual Studio Code Dev Container

compose.yaml

@@ -32,8 +32,10 @@ services:
       mysql:
         condition: service_healthy    # healthy status is indicated by `healthcheck` keyword
     build:
-      context: .
-      dockerfile: Containerfile
+      image: demoapp-backend:latest    # use built image
+      # Build image from Containerfile
+      # context: .
+      # dockerfile: Containerfile.multistage
     environment:
       # Externalized Spring Configuration: https://docs.spring.io/spring-boot/docs/1.5.6.RELEASE/reference/html/boot-features-external-config.html
       SPRING_DATASOURCE_USERNAME: root

pom.xml

@@ -15,6 +15,9 @@
 	<description>Backend application </description>
 	<properties>
 		<java.version>17</java.version>
+		<!-- Dockerfile Build Plugin: https://github.com/spotify/dockerfile-maven -->
+		<dockerfile-maven-version>1.4.13</dockerfile-maven-version>
+		<docker.registry.url></docker.registry.url>
 	</properties>
 	<dependencies>
 		<!-- Added by Paul Gilber (Start) -->
@@ -51,7 +54,42 @@
 				<groupId>org.springframework.boot</groupId>
 				<artifactId>spring-boot-maven-plugin</artifactId>
 			</plugin>
+			<!-- Dockerfile Build Plugin (tag: ${project.version}): https://github.com/spotify/dockerfile-maven -->
+			<plugin>
+				<groupId>com.spotify</groupId>
+				<artifactId>dockerfile-maven-plugin</artifactId>
+				<version>${dockerfile-maven-version}</version>
+				<executions>
+					<!-- Build Container Image -->
+					<execution>
+						<id>default</id>
+						<!-- https://github.com/spotify/dockerfile-maven/blob/master/docs/usage.md#maven-goals -->
+						<goals>
+							<goal>build</goal>
+						</goals>
+					</execution>
+					<!-- Create Container Image `latest` tag -->
+					<execution>
+						<id>latest-tag</id>
+						<goals>
+								<goal>tag</goal>
+						</goals>
+						<configuration>
+								<repository>${docker.registry.url}${project.artifactId}</repository>
+								<tag>latest</tag>
+						</configuration>
+					</execution>
+				</executions>
+				<configuration>
+					<dockerfile>Containerfile</dockerfile>
+					<repository>${docker.registry.url}${project.artifactId}</repository>
+					<tag>${project.version}</tag>
+					<contextDirectory>.</contextDirectory>
+					<buildArgs>
+						<JAR_FILE>${project.build.finalName}.jar</JAR_FILE>
+					</buildArgs>
+				</configuration>
+			</plugin>
 		</plugins>
 	</build>
-
 </project>