[Culprit-Finder] Merge lib/ to libs/.

appengine/findit/lib/cache_decorator.py

Index: appengine/findit/lib/cache_decorator.py
diff --git a/appengine/findit/lib/cache_decorator.py b/appengine/findit/lib/cache_decorator.py
deleted file mode 100644
index e02b12abba57b84f99ec1ce9e6ed2ec1f3aa436f..0000000000000000000000000000000000000000
--- a/appengine/findit/lib/cache_decorator.py
+++ /dev/null
@@ -1,136 +0,0 @@
-# Copyright 2015 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-"""This module provides a decorator to cache the results of a function.
-
-  Examples:
-  1. Decorate a function:
-    @cache_decorator.Cached()
-    def Test(a):
-      return a + a
-
-    Test('a')
-    Test('a')  # Returns the cached 'aa'.
-
-  2. Decorate a method in a class:
-    class Downloader(object):
-      def __init__(self, url, retries):
-        self.url = url
-        self.retries = retries
-
-      @property
-      def identifier(self):
-        return self.url
-
-      @cache_decorator.Cached():
-      def Download(self, path):
-        return urllib2.urlopen(self.url + '/' + path).read()
-
-      d1 = Downloader('http://url', 4)
-      d1.Download('path')
-
-      d2 = Downloader('http://url', 5)
-      d2.Download('path')  # Returned the cached downloaded data.
-"""
-
-import functools
-import hashlib
-import inspect
-import logging
-import pickle
-
-
-def _DefaultKeyGenerator(func, args, kwargs):
-  """Generates a key from the function and arguments passed to it.
-
-  Args:
-    func (function): An arbitrary function.
-    args (list): Positional arguments passed to ``func``.
-    kwargs (dict): Keyword arguments passed to ``func``.
-
-  Returns:
-    A string to represent a call to the given function with the given arguments.
-  """
-  params = inspect.getcallargs(func, *args, **kwargs)
-  for var_name in params:
-    if not hasattr(params[var_name], 'identifier'):
-      continue
-
-    if callable(params[var_name].identifier):
-      params[var_name] = params[var_name].identifier()
-    else:
-      params[var_name] = params[var_name].identifier
-
-  return hashlib.md5(pickle.dumps(params)).hexdigest()
-
-
-def Cached(namespace=None,
-           expire_time=0,
-           key_generator=_DefaultKeyGenerator,
-           cache=None):
-  """Returns a decorator to cache the decorated function's results.
-
-  However, if the function returns None, empty list/dict, empty string, or other
-  value that is evaluated as False, the results won't be cached.
-
-  This decorator is to cache results of different calls to the decorated
-  function, and avoid executing it again if the calls are equivalent. Two calls
-  are equivalent, if the namespace is the same and the keys generated by the
-  ``key_generator`` are the same.
-
-  The usage of this decorator requires that:
-  - If the default key generator is used, parameters passed to the decorated
-    function should be pickleable, or each of the parameter has an identifier
-    property or method which returns pickleable results.
-  - If the default cache is used, the returned results of the decorated
-    function should be pickleable.
-
-  Args:
-    namespace (str): A prefix to the key for the cache. Default to the
-        combination of module name and function name of the decorated function.
-    expire_time (int): Expiration time, relative number of seconds from current
-        time (up to 0 month). Defaults to 0 -- never expire.
-    key_generator (function): A function to generate a key to represent a call
-        to the decorated function. Defaults to :func:`_DefaultKeyGenerator`.
-    cache (Cache): An instance of an implementation of interface `Cache`.
-        Defaults to None.
-
-  Returns:
-    The cached results or the results of a new run of the decorated function.
-  """
-  def GetPrefix(func, namespace):
-    return namespace or '%s.%s' % (func.__module__, func.__name__)
-
-  def Decorator(func):
-    """Decorator to cache a function's results."""
-    @functools.wraps(func)
-    def Wrapped(*args, **kwargs):
-      prefix = GetPrefix(func, namespace)
-      key = '%s-%s' % (prefix, key_generator(func, args, kwargs))
-
-      try:
-        result = cache.Get(key)
-      except Exception:  # pragma: no cover.
-        result = None
-        logging.exception(
-            'Failed to get cached data for function %s.%s, args=%s, kwargs=%s',
-            func.__module__, func.__name__, repr(args), repr(kwargs))
-
-      if result is not None:
-        return result
-
-      result = func(*args, **kwargs)
-      if result:
-        try:
-          cache.Set(key, result, expire_time=expire_time)
-        except Exception:  # pragma: no cover.
-          logging.exception(
-              'Failed to cache data for function %s.%s, args=%s, kwargs=%s',
-              func.__module__, func.__name__, repr(args), repr(kwargs))
-
-      return result
-
-    return Wrapped
-
-  return Decorator