Add support for changing UID/GID (#216)

* Add support for changing UID/GID

* Revert volume definition in docker-compose file

0.17/Dockerfile

@@ -15,10 +15,12 @@ ENV PORT=34197 \
     CONFIG=/factorio/config \
     MODS=/factorio/mods \
     SCENARIOS=/factorio/scenarios \
-    SCRIPTOUTPUT=/factorio/script-output
+    SCRIPTOUTPUT=/factorio/script-output \
+    PUID=$PUID \
+    PGID=$PGID
 
 RUN mkdir -p /opt /factorio && \
-    apk add --update --no-cache pwgen su-exec binutils gettext libintl && \
+    apk add --update --no-cache pwgen su-exec binutils gettext libintl shadow && \
     apk add --update --no-cache --virtual .build-deps curl && \
     curl -sSL https://www.factorio.com/get-download/$VERSION/headless/linux64 \
         -o /tmp/factorio_headless_x64_$VERSION.tar.xz && \

0.17/docker-compose.yml

@@ -7,5 +7,6 @@ services:
      - "27015:27015/tcp"
     volumes:
      - /opt/factorio:/factorio
-#    user: 845:845
-#    user: 1000:1000
+#    environment:
+#      - PUID=1000
+#      - PGID=1000

0.17/files/docker-entrypoint.sh

@@ -35,6 +35,9 @@ if find -L $SAVES -iname \*.tmp.zip -mindepth 1 -print | grep -q .; then
 fi
 
 if [ "$(id -u)" = '0' ]; then
+  # Update the User and Group ID based on the PUID/PGID variables
+  usermod -u $PUID factorio
+  groupmod -g $PGID factorio
   # Take ownership of factorio data if running as root
   chown -R factorio:factorio $FACTORIO_VOL
   # Make sure we own temp