Adding Requests library

lib/requests/packages/urllib3/response.py

@@ -0,0 +1,202 @@
+# urllib3/response.py
+# Copyright 2008-2012 Andrey Petrov and contributors (see CONTRIBUTORS.txt)
+#
+# This module is part of urllib3 and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+import gzip
+import logging
+import zlib
+
+from io import BytesIO
+
+from .exceptions import DecodeError
+from .packages.six import string_types as basestring
+
+
+log = logging.getLogger(__name__)
+
+
+def decode_gzip(data):
+    gzipper = gzip.GzipFile(fileobj=BytesIO(data))
+    return gzipper.read()
+
+
+def decode_deflate(data):
+    try:
+        return zlib.decompress(data)
+    except zlib.error:
+        return zlib.decompress(data, -zlib.MAX_WBITS)
+
+
+class HTTPResponse(object):
+    """
+    HTTP Response container.
+
+    Backwards-compatible to httplib's HTTPResponse but the response ``body`` is
+    loaded and decoded on-demand when the ``data`` property is accessed.
+
+    Extra parameters for behaviour not present in httplib.HTTPResponse:
+
+    :param preload_content:
+        If True, the response's body will be preloaded during construction.
+
+    :param decode_content:
+        If True, attempts to decode specific content-encoding's based on headers
+        (like 'gzip' and 'deflate') will be skipped and raw data will be used
+        instead.
+
+    :param original_response:
+        When this HTTPResponse wrapper is generated from an httplib.HTTPResponse
+        object, it's convenient to include the original for debug purposes. It's
+        otherwise unused.
+    """
+
+    CONTENT_DECODERS = {
+        'gzip': decode_gzip,
+        'deflate': decode_deflate,
+    }
+
+    def __init__(self, body='', headers=None, status=0, version=0, reason=None,
+                 strict=0, preload_content=True, decode_content=True,
+                 original_response=None, pool=None, connection=None):
+        self.headers = headers or {}
+        self.status = status
+        self.version = version
+        self.reason = reason
+        self.strict = strict
+
+        self._decode_content = decode_content
+        self._body = body if body and isinstance(body, basestring) else None
+        self._fp = None
+        self._original_response = original_response
+
+        self._pool = pool
+        self._connection = connection
+
+        if hasattr(body, 'read'):
+            self._fp = body
+
+        if preload_content and not self._body:
+            self._body = self.read(decode_content=decode_content)
+
+    def get_redirect_location(self):
+        """
+        Should we redirect and where to?
+
+        :returns: Truthy redirect location string if we got a redirect status
+            code and valid location. ``None`` if redirect status and no
+            location. ``False`` if not a redirect status code.
+        """
+        if self.status in [301, 302, 303, 307]:
+            return self.headers.get('location')
+
+        return False
+
+    def release_conn(self):
+        if not self._pool or not self._connection:
+            return
+
+        self._pool._put_conn(self._connection)
+        self._connection = None
+
+    @property
+    def data(self):
+        # For backwords-compat with earlier urllib3 0.4 and earlier.
+        if self._body:
+            return self._body
+
+        if self._fp:
+            return self.read(cache_content=True)
+
+    def read(self, amt=None, decode_content=None, cache_content=False):
+        """
+        Similar to :meth:`httplib.HTTPResponse.read`, but with two additional
+        parameters: ``decode_content`` and ``cache_content``.
+
+        :param amt:
+            How much of the content to read. If specified, decoding and caching
+            is skipped because we can't decode partial content nor does it make
+            sense to cache partial content as the full response.
+
+        :param decode_content:
+            If True, will attempt to decode the body based on the
+            'content-encoding' header. (Overridden if ``amt`` is set.)
+
+        :param cache_content:
+            If True, will save the returned data such that the same result is
+            returned despite of the state of the underlying file object. This
+            is useful if you want the ``.data`` property to continue working
+            after having ``.read()`` the file object. (Overridden if ``amt`` is
+            set.)
+        """
+        content_encoding = self.headers.get('content-encoding')
+        decoder = self.CONTENT_DECODERS.get(content_encoding)
+        if decode_content is None:
+            decode_content = self._decode_content
+
+        if self._fp is None:
+            return
+
+        try:
+            if amt is None:
+                # cStringIO doesn't like amt=None
+                data = self._fp.read()
+            else:
+                return self._fp.read(amt)
+
+            try:
+                if decode_content and decoder:
+                    data = decoder(data)
+            except (IOError, zlib.error):
+                raise DecodeError("Received response with content-encoding: %s, but "
+                                  "failed to decode it." % content_encoding)
+
+            if cache_content:
+                self._body = data
+
+            return data
+
+        finally:
+            if self._original_response and self._original_response.isclosed():
+                self.release_conn()
+
+    @classmethod
+    def from_httplib(ResponseCls, r, **response_kw):
+        """
+        Given an :class:`httplib.HTTPResponse` instance ``r``, return a
+        corresponding :class:`urllib3.response.HTTPResponse` object.
+
+        Remaining parameters are passed to the HTTPResponse constructor, along
+        with ``original_response=r``.
+        """
+
+        # Normalize headers between different versions of Python
+        headers = {}
+        for k, v in r.getheaders():
+            # Python 3: Header keys are returned capitalised
+            k = k.lower()
+
+            has_value = headers.get(k)
+            if has_value: # Python 3: Repeating header keys are unmerged.
+                v = ', '.join([has_value, v])
+
+            headers[k] = v
+
+        # HTTPResponse objects in Python 3 don't have a .strict attribute
+        strict = getattr(r, 'strict', 0)
+        return ResponseCls(body=r,
+                           headers=headers,
+                           status=r.status,
+                           version=r.version,
+                           reason=r.reason,
+                           strict=strict,
+                           original_response=r,
+                           **response_kw)
+
+    # Backwards-compatibility methods for httplib.HTTPResponse
+    def getheaders(self):
+        return self.headers
+
+    def getheader(self, name, default=None):
+        return self.headers.get(name, default)