merged namespace

[sfa.git] / sfa / util / api.py

diff --git a/sfa/util/api.py b/sfa/util/api.py
index 5c5813f..1e131be 100644 (file)
--- a/sfa/util/api.py
+++ b/sfa/util/api.py
@@ -11,14 +11,13 @@ import traceback
 import string
 import xmlrpclib
 
+from sfa.util.sfalogging import sfa_logger
 from sfa.trust.auth import Auth
 from sfa.util.config import *
 from sfa.util.faults import *
-from sfa.util.debug import *
 from sfa.trust.credential import *
 from sfa.trust.certificate import *
 from sfa.util.namespace import *
-from sfa.util.sfalogging import *
 
 # See "2.2 Characters" in the XML specification:
 #
@@ -95,6 +94,27 @@ def import_deep(name):
         mod = getattr(mod, comp)
     return mod
 
+class ManagerWrapper:
+    """
+    This class acts as a wrapper around an SFA interface manager module, but
+    can be used with any python module. The purpose of this class is raise a 
+    SfaNotImplemented exception if the a someone attepmts to use an attribute 
+    (could be a callable) thats not available in the library by checking the
+    library using hasattr. This helps to communicate better errors messages 
+    to the users and developers in the event that a specifiec operation 
+    is not implemented by a libarary and will generally be more helpful than
+    the standard AttributeError         
+    """
+    def __init__(self, manager, interface):
+        self.manager = manager
+        self.interface = interface
+        
+    def __getattr__(self, method):
+        
+        if not hasattr(self.manager, method):
+            raise SfaNotImplemented(method, self.interface)
+        return getattr(self.manager, method)
+        
 class BaseAPI:
 
     cache = None
@@ -127,7 +147,7 @@ class BaseAPI:
         self.credential = None
         self.source = None 
         self.time_format = "%Y-%m-%d %H:%M:%S"
-        self.logger=get_sfa_logger()
+        self.logger=sfa_logger
         
         # load registries
         from sfa.server.registry import Registries
@@ -138,6 +158,33 @@ class BaseAPI:
         self.aggregates = Aggregates(self)
 
 
+    def get_interface_manager(self, manager_base = 'sfa.managers'):
+        """
+        Returns the appropriate manager module for this interface.
+        Modules are usually found in sfa/managers/
+        """
+        
+        if self.interface in ['registry']:
+            mgr_type = self.config.SFA_REGISTRY_TYPE
+            manager_module = manager_base + ".registry_manager_%s" % mgr_type
+        elif self.interface in ['aggregate']:
+            mgr_type = self.config.SFA_AGGREGATE_TYPE
+            manager_module = manager_base + ".aggregate_manager_%s" % mgr_type 
+        elif self.interface in ['slicemgr', 'sm']:
+            mgr_type = self.config.SFA_SM_TYPE
+            manager_module = manager_base + ".slice_manager_%s" % mgr_type
+        elif self.interface in ['component', 'cm']:
+            mgr_type = self.config.SFA_CM_TYPE
+            manager_module = manager_base + ".component_manager_%s" % mgr_type
+        else:
+            raise SfaAPIError("No manager for interface: %s" % self.interface)  
+        manager = __import__(manager_module, fromlist=[manager_base])
+        # this isnt necessary but will hlep to produce better error messages
+        # if someone tries to access an operation this manager doesn't implement  
+        manager = ManagerWrapper(manager, self.interface)
+
+        return manager
+
     def callable(self, method):
         """
         Return a new instance of the specified method.
@@ -192,9 +239,12 @@ class BaseAPI:
 
         try:
             result = self.call(source, method, *args)
+        except SfaFault, fault:
+            result = fault 
         except Exception, fault:
-            traceback.print_exc(file = log)
-            result = fault
+            sfa_logger.log_exc("BaseAPI.handle has caught Exception")
+            result = SfaAPIError(fault)
+
 
         # Return result
         response = self.prepare_response(result, method)
@@ -206,7 +256,7 @@ class BaseAPI:
         """   
  
         if self.protocol == 'xmlrpclib':
-            if not isinstance(result, Exception):
+            if not isinstance(result, SfaFault):
                 result = (result,)
             response = xmlrpclib.dumps(result, methodresponse = True, encoding = self.encoding, allow_none = 1)
         elif self.protocol == 'soap':