From 2bba5331db88542f6d646ae7aa39df3dd9e8e973 Mon Sep 17 00:00:00 2001
From: Tony Mack <tmack@cs.princeton.edu>
Date: Thu, 5 Aug 2010 23:33:41 +0000
Subject: [PATCH] BaseApi.get_interface_manager() wraps the manager
module/library in a ManagerWrapper class before returning it
---
sfa/util/api.py | 28 ++++++++++++++++++++++++++--
sfa/util/faults.py | 6 ++++--
sfa/util/nodemanager.py | 1 -
3 files changed, 30 insertions(+), 5 deletions(-)
diff --git a/sfa/util/api.py b/sfa/util/api.py
index 8343969e..cda8c887 100644
--- a/sfa/util/api.py
+++ b/sfa/util/api.py
@@ -95,6 +95,27 @@ 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
@@ -158,8 +179,11 @@ class BaseAPI:
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])
-
+ 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):
diff --git a/sfa/util/faults.py b/sfa/util/faults.py
index 5880fd90..8bf71e81 100644
--- a/sfa/util/faults.py
+++ b/sfa/util/faults.py
@@ -55,8 +55,10 @@ class SfaPermissionDenied(SfaFault):
SfaFault.__init__(self, 108, faultString, extra)
class SfaNotImplemented(SfaFault):
- def __init__(self, extra = None):
- faultString = "Not fully implemented"
+ def __init__(self, interface=None, extra = None):
+ faultString = "Not implemented"
+ if interface:
+ faultString += " at interface " + interface
SfaFault.__init__(self, 109, faultString, extra)
class SfaAPIError(SfaFault):
diff --git a/sfa/util/nodemanager.py b/sfa/util/nodemanager.py
index 99575c68..1671b9d6 100644
--- a/sfa/util/nodemanager.py
+++ b/sfa/util/nodemanager.py
@@ -15,7 +15,6 @@ class NodeManager:
def __call__(self, *args):
method = self.method
- ### WARNING -- hardwired name needs to be computed
sfa_slice_prefix = self.config.SFA_CM_SLICE_PREFIX
sfa_slice = sfa_slice_prefix + "_sfacm"
python = "/usr/bin/python"
--
2.47.0