FEAT: Installer based docker build

- added Dockerfile_installer which uses the JHOVE installer for a faster and more reliable way of building containers.

Author: carlwilson

Dockerfile_installer

@@ -0,0 +1,52 @@
+# See https://docs.docker.com/engine/userguide/eng-image/multistage-build/
+# First build the app on a maven open jdk 11 container
+ARG JHOVE_VERSION=1.32
+FROM eclipse-temurin:11-jdk-alpine AS app-installer
+ARG JHOVE_VERSION
+ENV JHOVE_VERSION=${JHOVE_VERSION}
+
+WORKDIR /tmp
+COPY docker-install.xml .
+RUN wget -O /tmp/jhove-installer.jar https://software.openpreservation.org/releases/jhove/jhove-${JHOVE_VERSION}.jar
+RUN java -jar jhove-installer.jar docker-install.xml
+
+# Now build a Java JRE for the Alpine application image
+# https://github.com/docker-library/docs/blob/master/eclipse-temurin/README.md#creating-a-jre-using-jlink
+FROM eclipse-temurin:11-jdk-alpine AS jre-builder
+
+# Create a custom Java runtime
+RUN "$JAVA_HOME/bin/jlink" \
+         --add-modules java.base,java.logging,java.xml,jdk.crypto.ec \
+         --strip-debug \
+         --no-man-pages \
+         --no-header-files \
+         --compress=2 \
+         --output /javaruntime
+
+# Now the final application image
+FROM alpine:3
+
+# Set for additional arguments passed to the java run command, no default
+ARG JAVA_OPTS
+ENV JAVA_OPTS=$JAVA_OPTS
+# Specify the veraPDF REST version if you want to (to be used in build automation)
+ARG JHOVE_VERSION
+ENV JHOVE_VERSION=${JHOVE_VERSION}
+
+# Copy the JRE from the previous stage
+ENV JAVA_HOME=/opt/java/openjdk
+ENV PATH "${JAVA_HOME}/bin:${PATH}"
+COPY --from=jre-builder /javaruntime $JAVA_HOME
+
+# Since this is a running network service we'll create an unprivileged account
+# which will be used to perform the rest of the work and run the actual service:
+RUN addgroup -S jhove && adduser -S -G jhove -h /opt/jhove jhove
+RUN mkdir --parents /var/opt/jhove/logs && chown -R jhove:jhove /var/opt/jhove
+
+USER jhove
+
+WORKDIR /opt/jhove
+# Copy the application from the previous stage
+COPY --from=app-installer /opt/jhove/ /opt/jhove/
+
+ENTRYPOINT ["/opt/jhove/jhove"]