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_run_cleanup(func, *args, **kwargs)
81
class OperationWithCleanups(object):
82
class ObjectWithCleanups(object):
83
"""A mixin for objects that hold a cleanup list.
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Subclass or client code can call add_cleanup and then later `cleanup_now`.
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self.cleanups = deque()
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def add_cleanup(self, cleanup_func, *args, **kwargs):
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"""Add a cleanup to run.
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Cleanups may be added at any time.
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Cleanups will be executed in LIFO order.
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self.cleanups.appendleft((cleanup_func, args, kwargs))
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def cleanup_now(self):
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_run_cleanups(self.cleanups)
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self.cleanups.clear()
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class OperationWithCleanups(ObjectWithCleanups):
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"""A way to run some code with a dynamic cleanup list.
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This provides a way to add cleanups while the function-with-cleanups is
104
126
def __init__(self, func):
127
super(OperationWithCleanups, self).__init__()
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self.cleanups = deque()
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def add_cleanup(self, cleanup_func, *args, **kwargs):
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"""Add a cleanup to run.
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Cleanups may be added at any time before or during the execution of
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self.func. Cleanups will be executed in LIFO order.
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self.cleanups.appendleft((cleanup_func, args, kwargs))
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130
def run(self, *args, **kwargs):
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131
return _do_with_cleanups(
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135
return _do_with_cleanups(
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self.cleanups, self.func, *args, **kwargs)
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def cleanup_now(self):
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_run_cleanups(self.cleanups)
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self.cleanups.clear()
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139
def _do_with_cleanups(cleanup_funcs, func, *args, **kwargs):
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"""Run `func`, then call all the cleanup_funcs.
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161
Unike `_run_cleanup`, `_do_with_cleanups` can propagate an exception from a
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162
cleanup, but only if there is no exception from func.
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# As correct as Python 2.4 allows.
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165
result = func(*args, **kwargs)
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# We have an exception from func already, so suppress cleanup errors.
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168
_run_cleanups(cleanup_funcs)
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# No exception from func, so allow the first exception from
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# cleanup_funcs to propagate if one occurs (but only after running all
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for cleanup, c_args, c_kwargs in cleanup_funcs:
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# XXX: Hmm, if KeyboardInterrupt arrives at exactly this line, we
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# won't run all cleanups... perhaps we should temporarily install a
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cleanup(*c_args, **c_kwargs)
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# This is the first cleanup to fail, so remember its
176
exc_info = sys.exc_info()
178
# We already have an exception to propagate, so log any errors
179
# but don't propagate them.
180
_run_cleanup(cleanup, *c_args, **kwargs)
181
if exc_info is not None:
182
raise exc_info[0], exc_info[1], exc_info[2]
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# No error, so we can return the result
170
# No exception from func, so allow first cleanup error to propgate.
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pending_cleanups = iter(cleanup_funcs)
173
for cleanup, c_args, c_kwargs in pending_cleanups:
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cleanup(*c_args, **c_kwargs)
176
# Still run the remaining cleanups but suppress any further errors.
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_run_cleanups(pending_cleanups)
179
# No error, so we can return the result