Initial Commit

lib/requests/packages/urllib3/response.py

@@ -0,0 +1,333 @@
+import zlib
+import io
+from socket import timeout as SocketTimeout
+
+from ._collections import HTTPHeaderDict
+from .exceptions import ProtocolError, DecodeError, ReadTimeoutError
+from .packages.six import string_types as basestring, binary_type
+from .connection import HTTPException, BaseSSLError
+from .util.response import is_fp_closed
+
+
+
+class DeflateDecoder(object):
+
+    def __init__(self):
+        self._first_try = True
+        self._data = binary_type()
+        self._obj = zlib.decompressobj()
+
+    def __getattr__(self, name):
+        return getattr(self._obj, name)
+
+    def decompress(self, data):
+        if not self._first_try:
+            return self._obj.decompress(data)
+
+        self._data += data
+        try:
+            return self._obj.decompress(data)
+        except zlib.error:
+            self._first_try = False
+            self._obj = zlib.decompressobj(-zlib.MAX_WBITS)
+            try:
+                return self.decompress(self._data)
+            finally:
+                self._data = None
+
+
+def _get_decoder(mode):
+    if mode == 'gzip':
+        return zlib.decompressobj(16 + zlib.MAX_WBITS)
+
+    return DeflateDecoder()
+
+
+class HTTPResponse(io.IOBase):
+    """
+    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.  This
+    class is also compatible with the Python standard library's :mod:`io`
+    module, and can hence be treated as a readable object in the context of that
+    framework.
+
+    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', 'deflate']
+    REDIRECT_STATUSES = [301, 302, 303, 307, 308]
+
+    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 = HTTPHeaderDict()
+        if headers:
+            self.headers.update(headers)
+        self.status = status
+        self.version = version
+        self.reason = reason
+        self.strict = strict
+        self.decode_content = decode_content
+
+        self._decoder = None
+        self._body = None
+        self._fp = None
+        self._original_response = original_response
+        self._fp_bytes_read = 0
+
+        if body and isinstance(body, (basestring, binary_type)):
+            self._body = body
+
+        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 self.REDIRECT_STATUSES:
+            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 tell(self):
+        """
+        Obtain the number of bytes pulled over the wire so far. May differ from
+        the amount of content returned by :meth:``HTTPResponse.read`` if bytes
+        are encoded on the wire (e.g, compressed).
+        """
+        return self._fp_bytes_read
+
+    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, caching is skipped
+            because it doesn't 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.
+
+        :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.)
+        """
+        # Note: content-encoding value should be case-insensitive, per RFC 7230
+        # Section 3.2
+        content_encoding = self.headers.get('content-encoding', '').lower()
+        if self._decoder is None:
+            if content_encoding in self.CONTENT_DECODERS:
+                self._decoder = _get_decoder(content_encoding)
+        if decode_content is None:
+            decode_content = self.decode_content
+
+        if self._fp is None:
+            return
+
+        flush_decoder = False
+
+        try:
+            try:
+                if amt is None:
+                    # cStringIO doesn't like amt=None
+                    data = self._fp.read()
+                    flush_decoder = True
+                else:
+                    cache_content = False
+                    data = self._fp.read(amt)
+                    if amt != 0 and not data:  # Platform-specific: Buggy versions of Python.
+                        # Close the connection when no data is returned
+                        #
+                        # This is redundant to what httplib/http.client _should_
+                        # already do.  However, versions of python released before
+                        # December 15, 2012 (http://bugs.python.org/issue16298) do
+                        # not properly close the connection in all cases. There is
+                        # no harm in redundantly calling close.
+                        self._fp.close()
+                        flush_decoder = True
+
+            except SocketTimeout:
+                # FIXME: Ideally we'd like to include the url in the ReadTimeoutError but
+                # there is yet no clean way to get at it from this context.
+                raise ReadTimeoutError(self._pool, None, 'Read timed out.')
+
+            except BaseSSLError as e:
+                # FIXME: Is there a better way to differentiate between SSLErrors?
+                if not 'read operation timed out' in str(e):  # Defensive:
+                    # This shouldn't happen but just in case we're missing an edge
+                    # case, let's avoid swallowing SSL errors.
+                    raise
+
+                raise ReadTimeoutError(self._pool, None, 'Read timed out.')
+
+            except HTTPException as e:
+                # This includes IncompleteRead.
+                raise ProtocolError('Connection broken: %r' % e, e)
+
+            self._fp_bytes_read += len(data)
+
+            try:
+                if decode_content and self._decoder:
+                    data = self._decoder.decompress(data)
+            except (IOError, zlib.error) as e:
+                raise DecodeError(
+                    "Received response with content-encoding: %s, but "
+                    "failed to decode it." % content_encoding, e)
+
+            if flush_decoder and decode_content and self._decoder:
+                buf = self._decoder.decompress(binary_type())
+                data += buf + self._decoder.flush()
+
+            if cache_content:
+                self._body = data
+
+            return data
+
+        finally:
+            if self._original_response and self._original_response.isclosed():
+                self.release_conn()
+
+    def stream(self, amt=2**16, decode_content=None):
+        """
+        A generator wrapper for the read() method. A call will block until
+        ``amt`` bytes have been read from the connection or until the
+        connection is closed.
+
+        :param amt:
+            How much of the content to read. The generator will return up to
+            much data per iteration, but may return less. This is particularly
+            likely when using compressed data. However, the empty string will
+            never be returned.
+
+        :param decode_content:
+            If True, will attempt to decode the body based on the
+            'content-encoding' header.
+        """
+        while not is_fp_closed(self._fp):
+            data = self.read(amt=amt, decode_content=decode_content)
+
+            if data:
+                yield data
+
+    @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``.
+        """
+
+        headers = HTTPHeaderDict()
+        for k, v in r.getheaders():
+            headers.add(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)
+
+    # Overrides from io.IOBase
+    def close(self):
+        if not self.closed:
+            self._fp.close()
+
+    @property
+    def closed(self):
+        if self._fp is None:
+            return True
+        elif hasattr(self._fp, 'closed'):
+            return self._fp.closed
+        elif hasattr(self._fp, 'isclosed'):  # Python 2
+            return self._fp.isclosed()
+        else:
+            return True
+
+    def fileno(self):
+        if self._fp is None:
+            raise IOError("HTTPResponse has no file to get a fileno from")
+        elif hasattr(self._fp, "fileno"):
+            return self._fp.fileno()
+        else:
+            raise IOError("The file-like object this HTTPResponse is wrapped "
+                          "around has no file descriptor")
+
+    def flush(self):
+        if self._fp is not None and hasattr(self._fp, 'flush'):
+            return self._fp.flush()
+
+    def readable(self):
+        # This method is required for `io` module compatibility.
+        return True
+
+    def readinto(self, b):
+        # This method is required for `io` module compatibility.
+        temp = self.read(len(b))
+        if len(temp) == 0:
+            return 0
+        else:
+            b[:len(temp)] = temp
+            return len(temp)