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# -*- coding: utf-8 -*-
# Copyright (C) 2008-2013 Team XBMC
# http://xbmc.org
#
# This Program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2, or (at your option)
# any later version.
#
# This Program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with XBMC; see the file COPYING. If not, see
# <http://www.gnu.org/licenses/>.
#
import urllib2, urlparse, gzip
from StringIO import StringIO
USER_AGENT = 'OpenAnything/1.0 +http://diveintopython.org/http_web_services/'
class SmartRedirectHandler(urllib2.HTTPRedirectHandler):
def http_error_301(self, req, fp, code, msg, headers):
result = urllib2.HTTPRedirectHandler.http_error_301(
self, req, fp, code, msg, headers)
result.status = code
return result
def http_error_302(self, req, fp, code, msg, headers):
result = urllib2.HTTPRedirectHandler.http_error_302(
self, req, fp, code, msg, headers)
result.status = code
return result
class DefaultErrorHandler(urllib2.HTTPDefaultErrorHandler):
def http_error_default(self, req, fp, code, msg, headers):
result = urllib2.HTTPError(
req.get_full_url(), code, msg, headers, fp)
result.status = code
return result
def openAnything(source, etag=None, lastmodified=None, agent=USER_AGENT):
'''URL, filename, or string --> stream
This function lets you define parsers that take any input source
(URL, pathname to local or network file, or actual data as a string)
and deal with it in a uniform manner. Returned object is guaranteed
to have all the basic stdio read methods (read, readline, readlines).
Just .close() the object when you're done with it.
If the etag argument is supplied, it will be used as the value of an
If-None-Match request header.
If the lastmodified argument is supplied, it must be a formatted
date/time string in GMT (as returned in the Last-Modified header of
a previous request). The formatted date/time will be used
as the value of an If-Modified-Since request header.
If the agent argument is supplied, it will be used as the value of a
User-Agent request header.
'''
if hasattr(source, 'read'):
return source
if source == '-':
return sys.stdin
if urlparse.urlparse(source)[0] == 'http':
# open URL with urllib2
request = urllib2.Request(source)
request.add_header('User-Agent', agent)
if etag:
request.add_header('If-None-Match', etag)
if lastmodified:
request.add_header('If-Modified-Since', lastmodified)
request.add_header('Accept-encoding', 'gzip')
opener = urllib2.build_opener(SmartRedirectHandler(), DefaultErrorHandler())
return opener.open(request)
# try to open with native open function (if source is a filename)
try:
return open(source)
except (IOError, OSError):
pass
# treat source as string
return StringIO(str(source))
def fetch(source, etag=None, last_modified=None, agent=USER_AGENT):
'''Fetch data and metadata from a URL, file, stream, or string'''
result = {}
f = openAnything(source, etag, last_modified, agent)
result['data'] = f.read()
if hasattr(f, 'headers'):
# save ETag, if the server sent one
result['etag'] = f.headers.get('ETag')
# save Last-Modified header, if the server sent one
result['lastmodified'] = f.headers.get('Last-Modified')
if f.headers.get('content-encoding', '') == 'gzip':
# data came back gzip-compressed, decompress it
result['data'] = gzip.GzipFile(fileobj=StringIO(result['data'])).read()
if hasattr(f, 'url'):
result['url'] = f.url
result['status'] = 200
if hasattr(f, 'status'):
result['status'] = f.status
f.close()
return result
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