x/tuskar-ui
Code Issues Proposed changes

Make @handle_errors support any kind of function

Browse Source 
This hack lets the @handle_errors decorator be used on
functions, methods, static methods and class methods,
without having to worry about how many parameters the
function takes, and whether there is "self" or not.

Change-Id: Ie34d200939dbadae0771da893e563995cd3ecf45
This commit is contained in:
Radomir Dopieralski 2014-03-05 11:36:17 +01:00
parent 73d72ebd0e
commit 434955839b
1 changed files with 21 additions and 6 deletions
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27
tuskar_ui/handle_errors.py
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@ -13,18 +13,20 @@
# under the License.
import functools
import inspect
import horizon.exceptions
def handle_errors(error_message, error_default=None):
def handle_errors(error_message, error_default=None, request_arg=None):
"""A decorator for adding default error handling to API calls.
It wraps the original method in a try-except block, with horizon's
error handling added.
Note: it should only be used on methods that take request as the first
(second after self or cls) argument.
Note: it should only be used on functions or methods that take request as
their argument (it has to be named "request", or ``request_arg`` has to be
provided, indicating which argument is the request).
The decorated method accepts a number of additional parameters:
@ -35,18 +37,31 @@ def handle_errors(error_message, error_default=None):
:param _error_ignore: ignore known errors
"""
def decorator(func):
# XXX This is an ugly hack for finding the 'request' argument.
if request_arg is None:
for _request_arg, name in enumerate(inspect.getargspec(func).args):
if name == 'request':
break
else:
raise RuntimeError(
"The handle_errors decorator requires 'request' as "
"an argument of the function or method being decorated")
else:
_request_arg = request_arg
@functools.wraps(func)
def wrapper(self, request, *args, **kwargs):
def wrapper(*args, **kwargs):
_error_handle = kwargs.pop('_error_handle', True)
_error_message = kwargs.pop('_error_message', error_message)
_error_default = kwargs.pop('_error_default', error_default)
_error_redirect = kwargs.pop('_error_redirect', None)
_error_ignore = kwargs.pop('_error_ignore', False)
if not _error_handle:
return func(self, request, *args, **kwargs)
return func(*args, **kwargs)
try:
return func(self, request, *args, **kwargs)
return func(*args, **kwargs)
except Exception:
request = args[_request_arg]
horizon.exceptions.handle(request, _error_message,
ignore=_error_ignore,
redirect=_error_redirect)