Update start-container script to check if data are already on NFS

src/gcube-start-container.sh

@@ -8,11 +8,15 @@ if [ -n "$EXIST_HOME" ]; then
       echo "eXist data should be already in place on NFS"
   elif [ -d "$EXIST_HOME/webapp/WEB-INF/data" ] ; then
       echo "First run: set up our directory structure on the NFS mountpoint"
-      mkdir -p /gcube-data/{db,backup}
-      mv $EXIST_HOME/webapp/WEB-INF/{data,logs,attachments} /gcube-data/db
-      for dir in {data,logs,attachments}; do
-        ln -s /gcube-data/db/${dir} $EXIST_HOME/webapp/WEB-INF/${dir}
-      done
+      mkdir -p /gcube-data/{db,backup} && mv $EXIST_HOME/webapp/WEB-INF/{data,logs,attachments} /gcube-data/db
+      if [ $? -eq 0 ]; then
+        for dir in {data,logs,attachments}; do
+          ln -s /gcube-data/db/${dir} $EXIST_HOME/webapp/WEB-INF/${dir}
+        done
+      elif
+        echo "Move failed: data already exists on NFS"
+        exit 1
+      fi
   else
       echo "Not a link, not a directory: a pony :-)?"
   fi