GoogleReader.py

#!/usr/bin/python
# coding=utf-8

# usage : 
# from GoogleReader import GoogleReader
# gr = GoogleReader('user','pass')
# atom = gr.getFeedCache('http://url.of/a/feed/')

import urllib, urllib2

class GoogleReader:
  def __init__(self, username, password):
    self.sid = None
    self.t = None

    params = urllib.urlencode({'Email':username,'Passwd':password,'service':'reader'})
    res = urllib2.urlopen('https://www.google.com/accounts/ClientLogin', params)
    for line in res.readlines():
      if line[:4] == 'SID=':
        self.sid = line[4:].strip()
    if not self.sid:
      raise Exception, "Couldn't retrieve SID token"

    req = urllib2.Request('http://www.google.com/reader/api/0/token')
    req.add_header('Cookie', 'SID=%s' % self.sid)
    res = urllib2.urlopen(req)
    self.t = res.read().strip()
    if not self.t:
      raise Exception, "Couldn't retrieve T token"

  def urlopen(self, url):
    if not url.startswith(('http://www.google.com/reader/','https://www.google.com/reader/')):
      raise Exception, "urlopen only supports Google Reader URLs"
    req = urllib2.Request(url)
    req.add_header('Cookie', 'SID=%s; T=%s' % (self.sid, self.t))
    return urllib2.urlopen(req)

  def getFeedCache(self, url, num=None):
    if not num or not isinstance(num, int):
      gr_url = 'http://www.google.com/reader/atom/feed/%s' % urllib.quote(url)
    else:
      gr_url = 'http://www.google.com/reader/atom/feed/%s?n=%d' % (urllib.quote(url),num)
    return self.urlopen(gr_url).read()