update_ted.py

#!/usr/bin/env python
import os
import feedparser
import pprint
import subprocess

TED_FEED = "http://feeds.feedburner.com/tedtalks_video"

def need_to_download(entries):
    for entry in entries:
        file_path = os.path.join(os.getcwd(), itunes_like_filename(entry))
        if os.path.exists(file_path):
            continue

        yield entry

def run(command):
    command = subprocess.Popen(command, shell = True)
    return command.wait()

def get_hd_url(entry):
    return entry['guid'].replace('.mp4', '_480.mp4')

def do_download(entry):
    hd_url = get_hd_url(entry)
    run('wget %s' % hd_url)
    do_rename(entry)

def do_rename(entry):
    hd_url = get_hd_url(entry)
    file_name = os.path.basename(hd_url)
    run("mv '%s' '%s'" % (file_name, itunes_like_filename(entry)))

def itunes_like_filename(entry):
    return entry['title'].replace(':', '_') + '.mp4'

feed = feedparser.parse(TED_FEED)
[do_download(e) for e in [entry for entry in need_to_download(feed['entries'])]]
#for entry in need_to_rename(feeds['entries']):
    #print entry