update dockerfile

Dockerfile

@@ -1,21 +1,17 @@
 # Settings.
 ARG USER_ID=3001
 ARG USER_NAME=projectmanagement
-ARG HOME_DIR=/$USER_NAME
-ARG SOURCE_DIR=$HOME_DIR/source
+ARG SOURCE_DIR=/$USER_NAME/source
 
 # Maven stage.
 FROM maven:3-openjdk-11-slim as maven
 ARG USER_ID
 ARG USER_NAME
-ARG HOME_DIR
 ARG SOURCE_DIR
 
-# Create the group (use a high ID to attempt to avoid conflits).
-RUN groupadd -g $USER_ID $USER_NAME
-
-# Create the user (use a high ID to attempt to avoid conflits).
-RUN useradd -d $HOME_DIR -m -u $USER_ID -g $USER_ID $USER_NAME
+# Create the user and group (use a high ID to attempt to avoid conflicts).
+RUN groupadd --non-unique -g $USER_ID $USER_NAME && \
+    useradd --non-unique -d /$USER_NAME -m -u $USER_ID -g $USER_ID $USER_NAME
 
 # Update the system.
 RUN apt-get update && apt-get upgrade -y
@@ -40,20 +36,17 @@ RUN mvn package -Pjar -DskipTests=true
 FROM openjdk:11-jre-slim
 ARG USER_ID
 ARG USER_NAME
-ARG HOME_DIR
 ARG SOURCE_DIR
 
-# Create the group (use a high ID to attempt to avoid conflits).
-RUN groupadd -g $USER_ID $USER_NAME
-
-# Create the user (use a high ID to attempt to avoid conflits).
-RUN useradd -d $HOME_DIR -m -u $USER_ID -g $USER_ID $USER_NAME
+# Create the user and group (use a high ID to attempt to avoid conflicts).
+RUN groupadd --non-unique -g $USER_ID $USER_NAME && \
+    useradd --non-unique -d /$USER_NAME -m -u $USER_ID -g $USER_ID $USER_NAME
 
 # Login as user.
 USER $USER_NAME
 
 # Set deployment directory.
-WORKDIR $HOME_DIR
+WORKDIR /$USER_NAME
 
 # Copy over the built artifact from the maven image.
 COPY --from=maven $SOURCE_DIR/target/ROOT.jar ./projectmanagement.jar