A python script that gets the list of the most popular subreddits and their number of subscribers

subreddit-data-dumper

import json
import time
from time import sleep
from urllib2 import Request
from urllib2 import build_opener
from urllib2 import HTTPError
import Cookie


def get_subreddits():
    
    subreddits_url = 'http://www.reddit.com/reddits'
    #We need this cookie in order to be sure to get the NSFW subreddits.
    c = Cookie.SimpleCookie()
    c['over18'] = '1'
    #We need to change the user-agent otherwise we will be blocked by reddit's servers.
    req_headers = {'User-Agent': 'reddit_stats by /u/quentinms', 'Cookie': c}
    
    after = ""
    #This is the maximum number of subreddits we can get at each call (default value is 25)
    limit = 100
 
    #While we have not reached the end of the list of subreddits
    while after != None :
        url = '%s.json?limit=%s&after=%s' % (subreddits_url, limit, after)
        req = Request(url, headers=req_headers)
        opener = build_opener()
        
        try:
            infos  = json.load(opener.open(req))
            after = infos['data']['after']
            extract_subreddits_from_json(infos)
            
            #We need to sleep 2 seconds between each API call as requested by reddit's rule.
            sleep(2)

        except urllib2.HTTPError:
            pass

#Get the name and number of subscribers for each subreddit in the list
def extract_subreddits_from_json(infos):
    for subreddit in infos['data']['children']:
        sub_name = subreddit['data']['url']
        sub_subscribers =  subreddit['data']['subscribers']
        
        print sub_name+", "+str(sub_subscribers)

get_subreddits()