Move get_context_from_function_and_args() to context.py

Word on the street is that exception.py may soon be deprecated,
and context.py is a better place anyway.

(Also removed an import of utils.py because /it/ imports exception.py.)

Change-Id: I856fc6f4558cc01ddca350ee4cfd4684db47475b

1 files changed, 15 insertions, 0 deletions

diff --git a/openstack/common/context.py b/openstack/common/context.py
index 35724e9..dd7dd04 100644
--- a/openstack/common/context.py
+++ b/openstack/common/context.py
@@ -22,6 +22,7 @@ Projects should subclass this class if they wish to enhance the request
 context or provide additional information in their specific WSGI pipeline.
 """
 
+import itertools
 import uuid
 
 
@@ -64,3 +65,17 @@ def get_admin_context(show_deleted="no"):
                              is_admin=True,
                              show_deleted=show_deleted)
     return context
+
+
+def get_context_from_function_and_args(function, args, kwargs):
+    """Find an arg of type RequestContext and return it.
+
+       This is useful in a couple of decorators where we don't
+       know much about the function we're wrapping.
+    """
+
+    for arg in itertools.chain(kwargs.values(), args):
+        if isinstance(arg, RequestContext):
+            return arg
+
+    return None