""" wuFetcher
	Usage: python wufetcher.py

	Author: Eric You XU, Washington University
	[Free to use for whatever purpose, absolutely NO WARRANTY]
	Kudos to 	gPowered: 			http://blog.gpowered.net/2007/08/google-reader-api-functions.html
				GoogleReaderAPI		http://code.google.com/p/pyrfeed/wiki/GoogleReaderAPI
"""

import urllib  
import urllib2  
import re  

login = 'wufetcher@gmail.com'  
password = 'wuFetcher2007'  
source = 'wuFetcher'

google_url = 'http://www.google.com'  
reader_url = google_url + '/reader'  
login_url = 'https://www.google.com/accounts/ClientLogin'  
get_feed_url = reader_url + '/atom/feed/'


def get_SID():  
	header = {'User-agent' : source}  
	post_data = urllib.urlencode({ 'Email': login, \
								'Passwd': password, \
								'service': 'reader', \
								'source': source, \
								'continue': google_url, })  
	# @see GoogleReaderAPI: Identification

	request = urllib2.Request(login_url, post_data, header)  
	try :  
		f = urllib2.urlopen(request)  
		result = f.read()
	except:  
		print 'Error logging in'
		exit(-1)  
	return re.search('SID=(\S*)', result).group(1)

def get_results(SID, url, number):  
	header = {'User-agent' : source}  
	header['Cookie']='Name=SID;SID=%s;Domain=.google.com;Path=/;Expires=160000000000' % SID
	post_data = urllib.urlencode({'n': str(number)})
	request = urllib2.Request(url+'?n='+str(number), None, header)  
	try :  
		f = urllib2.urlopen( request )  
		return f.read()
	except:  
		print 'Error getting data from %s' % url  
	return None

if __name__ == "__main__":
	sid= get_SID()
	feed_url= "http://feeds.feedburner.com/xumathena"
	# replace this url with the rss feed you want to fetch

	number = 10
	# replace this number with number of items you want to fetch

	result = get_results(sid, get_feed_url+feed_url.encode('utf-8'), number)
	f = open(feed_url.split('/')[-1], 'w')
	f.write(result)
	f.close()