Add existing GAM 3.21 code

oauth2client/util.py

@@ -0,0 +1,196 @@
+#!/usr/bin/env python
+#
+# Copyright 2010 Google Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+"""Common utility library."""
+
+__author__ = ['rafek@google.com (Rafe Kaplan)',
+              'guido@google.com (Guido van Rossum)',
+]
+__all__ = [
+  'positional',
+  'POSITIONAL_WARNING',
+  'POSITIONAL_EXCEPTION',
+  'POSITIONAL_IGNORE',
+]
+
+import inspect
+import logging
+import types
+import urllib
+import urlparse
+
+try:
+  from urlparse import parse_qsl
+except ImportError:
+  from cgi import parse_qsl
+
+logger = logging.getLogger(__name__)
+
+POSITIONAL_WARNING = 'WARNING'
+POSITIONAL_EXCEPTION = 'EXCEPTION'
+POSITIONAL_IGNORE = 'IGNORE'
+POSITIONAL_SET = frozenset([POSITIONAL_WARNING, POSITIONAL_EXCEPTION,
+                            POSITIONAL_IGNORE])
+
+positional_parameters_enforcement = POSITIONAL_WARNING
+
+def positional(max_positional_args):
+  """A decorator to declare that only the first N arguments my be positional.
+
+  This decorator makes it easy to support Python 3 style key-word only
+  parameters. For example, in Python 3 it is possible to write:
+
+    def fn(pos1, *, kwonly1=None, kwonly1=None):
+      ...
+
+  All named parameters after * must be a keyword:
+
+    fn(10, 'kw1', 'kw2')  # Raises exception.
+    fn(10, kwonly1='kw1')  # Ok.
+
+  Example:
+    To define a function like above, do:
+
+      @positional(1)
+      def fn(pos1, kwonly1=None, kwonly2=None):
+        ...
+
+    If no default value is provided to a keyword argument, it becomes a required
+    keyword argument:
+
+      @positional(0)
+      def fn(required_kw):
+        ...
+
+    This must be called with the keyword parameter:
+
+      fn()  # Raises exception.
+      fn(10)  # Raises exception.
+      fn(required_kw=10)  # Ok.
+
+    When defining instance or class methods always remember to account for
+    'self' and 'cls':
+
+      class MyClass(object):
+
+        @positional(2)
+        def my_method(self, pos1, kwonly1=None):
+          ...
+
+        @classmethod
+        @positional(2)
+        def my_method(cls, pos1, kwonly1=None):
+          ...
+
+  The positional decorator behavior is controlled by
+  util.positional_parameters_enforcement, which may be set to
+  POSITIONAL_EXCEPTION, POSITIONAL_WARNING or POSITIONAL_IGNORE to raise an
+  exception, log a warning, or do nothing, respectively, if a declaration is
+  violated.
+
+  Args:
+    max_positional_arguments: Maximum number of positional arguments. All
+      parameters after the this index must be keyword only.
+
+  Returns:
+    A decorator that prevents using arguments after max_positional_args from
+    being used as positional parameters.
+
+  Raises:
+    TypeError if a key-word only argument is provided as a positional
+    parameter, but only if util.positional_parameters_enforcement is set to
+    POSITIONAL_EXCEPTION.
+  """
+  def positional_decorator(wrapped):
+    def positional_wrapper(*args, **kwargs):
+      if len(args) > max_positional_args:
+        plural_s = ''
+        if max_positional_args != 1:
+          plural_s = 's'
+        message = '%s() takes at most %d positional argument%s (%d given)' % (
+            wrapped.__name__, max_positional_args, plural_s, len(args))
+        if positional_parameters_enforcement == POSITIONAL_EXCEPTION:
+          raise TypeError(message)
+        elif positional_parameters_enforcement == POSITIONAL_WARNING:
+          logger.warning(message)
+        else: # IGNORE
+          pass
+      return wrapped(*args, **kwargs)
+    return positional_wrapper
+
+  if isinstance(max_positional_args, (int, long)):
+    return positional_decorator
+  else:
+    args, _, _, defaults = inspect.getargspec(max_positional_args)
+    return positional(len(args) - len(defaults))(max_positional_args)
+
+
+def scopes_to_string(scopes):
+  """Converts scope value to a string.
+
+  If scopes is a string then it is simply passed through. If scopes is an
+  iterable then a string is returned that is all the individual scopes
+  concatenated with spaces.
+
+  Args:
+    scopes: string or iterable of strings, the scopes.
+
+  Returns:
+    The scopes formatted as a single string.
+  """
+  if isinstance(scopes, types.StringTypes):
+    return scopes
+  else:
+    return ' '.join(scopes)
+
+
+def dict_to_tuple_key(dictionary):
+  """Converts a dictionary to a tuple that can be used as an immutable key.
+
+  The resulting key is always sorted so that logically equivalent dictionaries
+  always produce an identical tuple for a key.
+
+  Args:
+    dictionary: the dictionary to use as the key.
+
+  Returns:
+    A tuple representing the dictionary in it's naturally sorted ordering.
+  """
+  return tuple(sorted(dictionary.items()))
+
+
+def _add_query_parameter(url, name, value):
+  """Adds a query parameter to a url.
+
+  Replaces the current value if it already exists in the URL.
+
+  Args:
+    url: string, url to add the query parameter to.
+    name: string, query parameter name.
+    value: string, query parameter value.
+
+  Returns:
+    Updated query parameter. Does not update the url if value is None.
+  """
+  if value is None:
+    return url
+  else:
+    parsed = list(urlparse.urlparse(url))
+    q = dict(parse_qsl(parsed[4]))
+    q[name] = value
+    parsed[4] = urllib.urlencode(q)
+    return urlparse.urlunparse(parsed)