support commandline application initialization

You can run your Ryu applicaiton in the following way:

$ ryu-manager yourapp.py

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Isaku Yamahata <yamahata@valinux.co.jp>

bin/ryu-manager

@@ -1,6 +1,6 @@
 #!/usr/bin/env python
 #
-# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011, 2012 Nippon Telegraph and Telephone Corporation.
 # Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -35,17 +35,18 @@ from ryu.controller import controller
 
 FLAGS = gflags.FLAGS
 gflags.DEFINE_multistring('app_lists',
-                          ['ryu.app.simple_isolation',
-                           'ryu.app.rest',
-                           ],
+                          [],
                           'application module name to run')
 
 
 def main():
     utils.find_flagfile()
-    _args = FLAGS(sys.argv)
+    args = FLAGS(sys.argv)
     log.init_log()
 
+    if len(args) > 1:
+        FLAGS.app_lists += args[1:]
+
     app_mgr = AppManager()
     app_mgr.load_apps(FLAGS.app_lists)
     contexts = app_mgr.create_contexts()

ryu/utils.py

@@ -24,7 +24,15 @@
 
 
 def import_module(modname):
-    __import__(modname)
+    try:
+        __import__(modname)
+    except:
+        sys.path.append(os.path.dirname(os.path.abspath(modname)))
+        name = os.path.basename(modname)
+        if name.endswith('.py'):
+            name = name[:-3]
+        __import__(name)
+        return sys.modules[name]
     return sys.modules[modname]