Defer install to first run

Dockerfile

@@ -2,12 +2,9 @@ FROM zombi/steam:latest
 MAINTAINER MadMaurice <madmaurice@zom.bi>
 EXPOSE 27015/udp
 
-RUN /opt/steamcmd/steamcmd.sh +login anonymous +force_install_dir /home/steam/insurgency +app_update 237410 validate +quit &&\
-	chown -R steam /home/steam/insurgency
-
-WORKDIR /home/steam/insurgency
-
+ADD bin/entrypoint.sh /entrypoint.sh
+RUN chmod +xr /entrypoint.sh
 USER steam
 
-ENTRYPOINT ["./srcds_run", "-game", "insurgency"]
-CMD ["-console", "+mapgroup", "mg_active", "+map", "ministry", "+maxplayers", "8", "+mapcyclefile","mapcycle_cooperative.txt"]
+ENTRYPOINT ["/entrypoint.sh"]
+CMD ["+mapgroup", "mg_active", "+map", "ministry", "+maxplayers", "8", "+mapcyclefile", "mapcycle_cooperative.txt"]

bin/entrypoint.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+
+# what are we trying to install?
+game_nm=insurgency
+game_id=237410
+
+# install game to this directory
+installdir=/home/steam/games/$game_nm
+  
+# if path does not exist, create it
+mkdir -p $installdir
+
+if [ -w $installdir ] # can we write into the directory?
+then
+        # Install or update the game in /home/steam/games/[game name]
+        /opt/steamcmd/steamcmd.sh \
+                +login anonymous \
+                +force_install_dir $installdir \
+                +app_update $game_id validate \
+                +quit
+else
+        # install dir maybe mounted read-only, simply
+        # skip installing/updating and inform the user.
+        echo "Skipped game installation."
+fi
+
+# run the next commands from the installdir
+cd $installdir
+
+# is the game launcher not executable?
+if [ ! -x ./srcds_run ]
+then
+        # we cant run the game then.
+        echo "game launcher not found, installed incorrectly?"
+        exit 1
+fi
+
+# launch the game!
+exec ./srcds_run \
+        -game $game_nm \
+        -console \
+        $@ # append all remaining parameters