scrapy/scrapy/http/response/text.py

88 lines
3.0 KiB
Python

"""
This module implements the TextResponse class which adds encoding handling and
discovering (through HTTP headers) to base Response class.
See documentation in docs/topics/request-response.rst
"""
import re
from scrapy.xlib.BeautifulSoup import UnicodeDammit
from scrapy.http.response import Response
from scrapy.utils.python import memoizemethod_noargs
from scrapy.conf import settings
class TextResponse(Response):
_DEFAULT_ENCODING = settings['DEFAULT_RESPONSE_ENCODING']
_ENCODING_RE = re.compile(r'charset=([\w-]+)', re.I)
__slots__ = ['_encoding', '_body_inferred_encoding']
def __init__(self, url, status=200, headers=None, body=None, meta=None, \
flags=None, encoding=None):
self._encoding = encoding
self._body_inferred_encoding = None
super(TextResponse, self).__init__(url, status, headers, body, meta, flags)
def _get_url(self):
return self._url
def _set_url(self, url):
if isinstance(url, unicode):
if self.encoding is None:
raise TypeError('Cannot convert unicode url - %s has no encoding' %
type(self).__name__)
self._url = url.encode(self.encoding)
else:
super(TextResponse, self)._set_url(url)
url = property(_get_url, _set_url)
def _set_body(self, body):
self._body = ''
if isinstance(body, unicode):
if self.encoding is None:
raise TypeError('Cannot convert unicode body - %s has no encoding' %
type(self).__name__)
self._body = body.encode(self._encoding)
else:
super(TextResponse, self)._set_body(body)
def replace(self, *args, **kwargs):
kwargs.setdefault('encoding', getattr(self, '_encoding', None))
return Response.replace(self, *args, **kwargs)
@property
def encoding(self):
return self._encoding or self.headers_encoding() or self.body_encoding()
@memoizemethod_noargs
def headers_encoding(self):
content_type = self.headers.get('Content-Type')
if content_type:
encoding = self._ENCODING_RE.search(content_type)
if encoding:
return encoding.group(1)
@memoizemethod_noargs
def body_as_unicode(self):
"""Return body as unicode"""
possible_encodings = (self._encoding, self.headers_encoding(), \
self._body_declared_encoding())
dammit = UnicodeDammit(self.body, possible_encodings)
self._body_inferred_encoding = dammit.originalEncoding
if self._body_inferred_encoding in ('ascii', None):
self._body_inferred_encoding = self._DEFAULT_ENCODING
return dammit.unicode
def body_encoding(self):
if self._body_inferred_encoding is None:
self.body_as_unicode()
return self._body_inferred_encoding
def _body_declared_encoding(self):
# implemented in subclasses (XmlResponse, HtmlResponse)
return None