Initial checkin of openstack shell

diff --git a/sfa/openstack/openstack_shell.py b/sfa/openstack/openstack_shell.py
new file mode 100644 (file)
index 0000000..d2c19fb
--- /dev/null
+++ b/sfa/openstack/openstack_shell.py
@@ -0,0 +1,69 @@
+import sys
+import xmlrpclib
+import socket
+from urlparse import urlparse
+
+from sfa.util.sfalogging import logger
+
+class OpenstackShell:
+    """
+    A simple xmlrpc shell to a myplc instance
+    This class can receive all Openstack calls to the underlying testbed
+    """
+    
+    # dont care about limiting calls yet 
+    direct_calls = []
+    alias_calls = {}
+
+
+    # use the 'capability' auth mechanism for higher performance when the PLC db is local    
+    def __init__ ( self, config ) :
+        url = config.SFA_PLC_URL
+        # try to figure if the url is local
+        hostname=urlparse(url).hostname
+        is_local=False
+        if hostname == 'localhost': is_local=True
+        # otherwise compare IP addresses; 
+        # this might fail for any number of reasons, so let's harden that
+        try:
+            # xxx todo this seems to result in a DNS request for each incoming request to the AM
+            # should be cached or improved
+            url_ip=socket.gethostbyname(hostname)
+            local_ip=socket.gethostbyname(socket.gethostname())
+            if url_ip==local_ip: is_local=True
+        except:
+            pass
+
+
+        # Openstack provides a RESTful api but it is very limited, so we will
+        # ignore it for now and always use the native openstack (nova) library.
+        # This of course will not work if sfa is not installed on the same machine
+        # as the openstack-compute package.   
+        if is_local:
+            try:
+                from nova.auth.manager import AuthManager, db, context
+                direct_access=True
+            except:
+                direct_access=False
+        if is_local and direct_access:
+            
+            logger.debug('openstack access - native')
+            self.auth = context.get_admin_context()
+            # AuthManager isnt' really useful for much yet but it's
+            # more convenient to use than the db reference which requires
+            # a context. Lets hold onto the AuthManager reference for now.
+            #self.proxy = AuthManager()
+            self.auth_manager = AuthManager()
+            self.proxy = db
+
+        else:
+            self.auth = None
+            self.proxy = None
+            logger.debug('openstack access - REST')
+            raise SfaNotImplemented('openstack access - Rest')
+
+    def __getattr__(self, name):
+        def func(*args, **kwds):
+            result=getattr(self.proxy, name)(self.auth, *args, **kwds)
+            return result
+        return func