CORD-2748 Automatically restart TOSCA engine when connection terminates

Change-Id: Id70442e274cd68eea47de67c98f6c62b7330f764
diff --git a/src/tosca/generator.py b/src/tosca/generator.py
index 6d82150..13472f9 100644
--- a/src/tosca/generator.py
+++ b/src/tosca/generator.py
@@ -26,15 +26,19 @@
 
 class TOSCA_Generator:
 
-    def _clean(self, dir=TOSCA_DEFS_DIR):
+    def clean(self, dir=TOSCA_DEFS_DIR):
         filesToRemove = [f for f in os.listdir(dir)]
         for f in filesToRemove:
             if not f.startswith('.'):
                 os.remove(dir + '/' + f)
 
+    def clean_keys(self, dir=TOSCA_KEYS_DIR):
+        keys_fn = os.path.join(dir, "KEYS.py")
+        if os.path.exists(keys_fn):
+            os.remove(keys_fn)
+
     def generate(self, client):
         print "[XOS-TOSCA] Generating TOSCA"
-        self._clean()
 
         try:
             xproto = client.utility.GetXproto(Empty())