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Diffstat (limited to 'requests/packages/urllib3/_collections.py')
| -rw-r--r-- | requests/packages/urllib3/_collections.py | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/requests/packages/urllib3/_collections.py b/requests/packages/urllib3/_collections.py new file mode 100644 index 0000000..279416c --- /dev/null +++ b/requests/packages/urllib3/_collections.py @@ -0,0 +1,323 @@ +from collections import Mapping, MutableMapping +try: + from threading import RLock +except ImportError: # Platform-specific: No threads available + class RLock: + def __enter__(self): + pass + + def __exit__(self, exc_type, exc_value, traceback): + pass + + +try: # Python 2.7+ + from collections import OrderedDict +except ImportError: + from .packages.ordered_dict import OrderedDict +from .packages.six import iterkeys, itervalues, PY3 + + +__all__ = ['RecentlyUsedContainer', 'HTTPHeaderDict'] + + +_Null = object() + + +class RecentlyUsedContainer(MutableMapping): + """ + Provides a thread-safe dict-like container which maintains up to + ``maxsize`` keys while throwing away the least-recently-used keys beyond + ``maxsize``. + + :param maxsize: + Maximum number of recent elements to retain. + + :param dispose_func: + Every time an item is evicted from the container, + ``dispose_func(value)`` is called. Callback which will get called + """ + + ContainerCls = OrderedDict + + def __init__(self, maxsize=10, dispose_func=None): + self._maxsize = maxsize + self.dispose_func = dispose_func + + self._container = self.ContainerCls() + self.lock = RLock() + + def __getitem__(self, key): + # Re-insert the item, moving it to the end of the eviction line. + with self.lock: + item = self._container.pop(key) + self._container[key] = item + return item + + def __setitem__(self, key, value): + evicted_value = _Null + with self.lock: + # Possibly evict the existing value of 'key' + evicted_value = self._container.get(key, _Null) + self._container[key] = value + + # If we didn't evict an existing value, we might have to evict the + # least recently used item from the beginning of the container. + if len(self._container) > self._maxsize: + _key, evicted_value = self._container.popitem(last=False) + + if self.dispose_func and evicted_value is not _Null: + self.dispose_func(evicted_value) + + def __delitem__(self, key): + with self.lock: + value = self._container.pop(key) + + if self.dispose_func: + self.dispose_func(value) + + def __len__(self): + with self.lock: + return len(self._container) + + def __iter__(self): + raise NotImplementedError('Iteration over this class is unlikely to be threadsafe.') + + def clear(self): + with self.lock: + # Copy pointers to all values, then wipe the mapping + values = list(itervalues(self._container)) + self._container.clear() + + if self.dispose_func: + for value in values: + self.dispose_func(value) + + def keys(self): + with self.lock: + return list(iterkeys(self._container)) + + +_dict_setitem = dict.__setitem__ +_dict_getitem = dict.__getitem__ +_dict_delitem = dict.__delitem__ +_dict_contains = dict.__contains__ +_dict_setdefault = dict.setdefault + + +class HTTPHeaderDict(dict): + """ + :param headers: + An iterable of field-value pairs. Must not contain multiple field names + when compared case-insensitively. + + :param kwargs: + Additional field-value pairs to pass in to ``dict.update``. + + A ``dict`` like container for storing HTTP Headers. + + Field names are stored and compared case-insensitively in compliance with + RFC 7230. Iteration provides the first case-sensitive key seen for each + case-insensitive pair. + + Using ``__setitem__`` syntax overwrites fields that compare equal + case-insensitively in order to maintain ``dict``'s api. For fields that + compare equal, instead create a new ``HTTPHeaderDict`` and use ``.add`` + in a loop. + + If multiple fields that are equal case-insensitively are passed to the + constructor or ``.update``, the behavior is undefined and some will be + lost. + + >>> headers = HTTPHeaderDict() + >>> headers.add('Set-Cookie', 'foo=bar') + >>> headers.add('set-cookie', 'baz=quxx') + >>> headers['content-length'] = '7' + >>> headers['SET-cookie'] + 'foo=bar, baz=quxx' + >>> headers['Content-Length'] + '7' + """ + + def __init__(self, headers=None, **kwargs): + dict.__init__(self) + if headers is not None: + if isinstance(headers, HTTPHeaderDict): + self._copy_from(headers) + else: + self.extend(headers) + if kwargs: + self.extend(kwargs) + + def __setitem__(self, key, val): + return _dict_setitem(self, key.lower(), (key, val)) + + def __getitem__(self, key): + val = _dict_getitem(self, key.lower()) + return ', '.join(val[1:]) + + def __delitem__(self, key): + return _dict_delitem(self, key.lower()) + + def __contains__(self, key): + return _dict_contains(self, key.lower()) + + def __eq__(self, other): + if not isinstance(other, Mapping) and not hasattr(other, 'keys'): + return False + if not isinstance(other, type(self)): + other = type(self)(other) + return dict((k1, self[k1]) for k1 in self) == dict((k2, other[k2]) for k2 in other) + + def __ne__(self, other): + return not self.__eq__(other) + + values = MutableMapping.values + get = MutableMapping.get + update = MutableMapping.update + + if not PY3: # Python 2 + iterkeys = MutableMapping.iterkeys + itervalues = MutableMapping.itervalues + + __marker = object() + + def pop(self, key, default=__marker): + '''D.pop(k[,d]) -> v, remove specified key and return the corresponding value. + If key is not found, d is returned if given, otherwise KeyError is raised. + ''' + # Using the MutableMapping function directly fails due to the private marker. + # Using ordinary dict.pop would expose the internal structures. + # So let's reinvent the wheel. + try: + value = self[key] + except KeyError: + if default is self.__marker: + raise + return default + else: + del self[key] + return value + + def discard(self, key): + try: + del self[key] + except KeyError: + pass + + def add(self, key, val): + """Adds a (name, value) pair, doesn't overwrite the value if it already + exists. + + >>> headers = HTTPHeaderDict(foo='bar') + >>> headers.add('Foo', 'baz') + >>> headers['foo'] + 'bar, baz' + """ + key_lower = key.lower() + new_vals = key, val + # Keep the common case aka no item present as fast as possible + vals = _dict_setdefault(self, key_lower, new_vals) + if new_vals is not vals: + # new_vals was not inserted, as there was a previous one + if isinstance(vals, list): + # If already several items got inserted, we have a list + vals.append(val) + else: + # vals should be a tuple then, i.e. only one item so far + # Need to convert the tuple to list for further extension + _dict_setitem(self, key_lower, [vals[0], vals[1], val]) + + def extend(self, *args, **kwargs): + """Generic import function for any type of header-like object. + Adapted version of MutableMapping.update in order to insert items + with self.add instead of self.__setitem__ + """ + if len(args) > 1: + raise TypeError("extend() takes at most 1 positional " + "arguments ({} given)".format(len(args))) + other = args[0] if len(args) >= 1 else () + + if isinstance(other, HTTPHeaderDict): + for key, val in other.iteritems(): + self.add(key, val) + elif isinstance(other, Mapping): + for key in other: + self.add(key, other[key]) + elif hasattr(other, "keys"): + for key in other.keys(): + self.add(key, other[key]) + else: + for key, value in other: + self.add(key, value) + + for key, value in kwargs.items(): + self.add(key, value) + + def getlist(self, key): + """Returns a list of all the values for the named field. Returns an + empty list if the key doesn't exist.""" + try: + vals = _dict_getitem(self, key.lower()) + except KeyError: + return [] + else: + if isinstance(vals, tuple): + return [vals[1]] + else: + return vals[1:] + + # Backwards compatibility for httplib + getheaders = getlist + getallmatchingheaders = getlist + iget = getlist + + def __repr__(self): + return "%s(%s)" % (type(self).__name__, dict(self.itermerged())) + + def _copy_from(self, other): + for key in other: + val = _dict_getitem(other, key) + if isinstance(val, list): + # Don't need to convert tuples + val = list(val) + _dict_setitem(self, key, val) + + def copy(self): + clone = type(self)() + clone._copy_from(self) + return clone + + def iteritems(self): + """Iterate over all header lines, including duplicate ones.""" + for key in self: + vals = _dict_getitem(self, key) + for val in vals[1:]: + yield vals[0], val + + def itermerged(self): + """Iterate over all headers, merging duplicate ones together.""" + for key in self: + val = _dict_getitem(self, key) + yield val[0], ', '.join(val[1:]) + + def items(self): + return list(self.iteritems()) + + @classmethod + def from_httplib(cls, message): # Python 2 + """Read headers from a Python 2 httplib message object.""" + # python2.7 does not expose a proper API for exporting multiheaders + # efficiently. This function re-reads raw lines from the message + # object and extracts the multiheaders properly. + headers = [] + + for line in message.headers: + if line.startswith((' ', '\t')): + key, value = headers[-1] + headers[-1] = (key, value + '\r\n' + line.rstrip()) + continue + + key, value = line.split(':', 1) + headers.append((key, value.strip())) + + return cls(headers) |