manage group from entrypoint

Dockerfile

@@ -10,8 +10,6 @@ WORKDIR /app
 EXPOSE 5000
 COPY ./dist .
 COPY entrypoint.sh /
-
-RUN groupadd -g 999 bitwarden \
-    && chmod +x /entrypoint.sh
+RUN chmod +x /entrypoint.sh
 
 ENTRYPOINT ["/entrypoint.sh"]

entrypoint.sh

@@ -1,33 +1,65 @@
 #!/bin/bash
 
+# Setup
+
+GROUPNAME="bitwarden"
 USERNAME="bitwarden"
-NOUSER=`id -u $USERNAME > /dev/null 2>&1; echo $?`
+
+CURRENTGID=`getent group $GROUPNAME | cut -d: -f3`
+LGID=${LOCAL_GID:-999}
+
+CURRENTUID=`id -u $USERNAME`
+NOUSER=`$CURRENTUID > /dev/null 2>&1; echo $?`
 LUID=${LOCAL_UID:-999}
 
 # Step down from host root
+
+if [ $LGID == 0 ]
+then
+    LGID=999
+fi
+
 if [ $LUID == 0 ]
 then
     LUID=999
 fi
 
-if [ $NOUSER == 0 ] && [ `id -u $USERNAME` != $LUID ]
+# Create group
+
+if [ $CURRENTGID ]
+then
+    if [ $CURRENTGID != $LGID ]
+    then
+        groupmod -g $LGID $GROUPNAME
+    fi
+else
+    groupadd -g $LGID $GROUPNAME
+fi
+
+# Create user and assign group
+
+if [ $NOUSER == 0 ] && [ $CURRENTUID != $LUID ]
 then
     usermod -u $LUID $USERNAME
 elif [ $NOUSER == 1 ]
 then
-    useradd -r -u $LUID -g $USERNAME $USERNAME
+    useradd -r -u $LUID -g $GROUPNAME $USERNAME
 fi
 
+# Make home directory for user
+
 if [ ! -d "/home/$USERNAME" ]
 then
     mkhomedir_helper $USERNAME
 fi
 
-chown -R $USERNAME:$USERNAME /etc/bitwarden
+# The rest...
+
+chown -R $USERNAME:$GROUPNAME /etc/bitwarden
 cp /etc/bitwarden/web/settings.js /app/js/settings.js
 cp /etc/bitwarden/web/app-id.json /app/app-id.json
-chown -R $USERNAME:$USERNAME /app
-chown -R $USERNAME:$USERNAME /bitwarden_server
+chown -R $USERNAME:$GROUPNAME /app
+chown -R $USERNAME:$GROUPNAME /bitwarden_server
 
-gosu $USERNAME:$USERNAME dotnet /bitwarden_server/Server.dll \
+gosu $USERNAME:$GROUPNAME dotnet /bitwarden_server/Server.dll \
     /contentRoot=/app /webRoot=. /serveUnknown=false