3-Dockerfile-use-workdir

# Continue with the previous dockerfile
# Set the /opt/app directory as WORKDIR and remove the mkdir instruction:
# WORKDIR /opt/app
#
# Remove unnecessary /opt/app references
#
# Build the image
# Run the container
# Verify it builds and starts successfully
# You will not notice any difference, only the Dockerfile is more readable
FROM eclipse-temurin:17.0.7_7-jre-alpine@sha256:dd8238c151293ae6a7c22898ef2f0df2af8a05786aef73ccd3248e73765969ed
WORKDIR /opt/app
RUN addgroup --system javauser && adduser -S -s /usr/sbin/nologin -G javauser javauser
ARG JAR_FILE
ADD target/${JAR_FILE} app.jar
RUN chown -R javauser:javauser .
USER javauser
CMD ["java", "-jar", "app.jar"]