Python Code to Search Youtube Comments

Today I am sharing a code that I wrote few months ago. It searches the comments in youtube video and stores those in a database (postgresql in my code). I used the youtube api. Instead of describing the code in detail, I think posting the code should be enough. If you have any queries or any suggestion to improve the code, feel free to comment.

 import gdata.youtube  
 import gdata.youtube.service  
 import psycopg2  
 import sys  
 from datetime import datetime  
 import time  
 import re  
   
   
   
   
 try:  
   # you should read these from a config file  
   conn = psycopg2.connect(host='localhost', database='databae_name', user='user', password='pass')  
   conn.autocommit = True  
   cursor = conn.cursor()  
 except psycopg2.DatabaseError, e:  
   print 'Error %s' % e    
   sys.exit(1)  
   
   
    
 def since_epoch(date_string):  
   return int(time.mktime(datetime.strptime(date_string, "%Y-%m-%dT%H:%M:%S.%fZ").timetuple()) * 1000)  
    
   
   
 def comments_generator(client, video_id):  
   comment_feed = client.GetYouTubeVideoCommentFeed(video_id=video_id)  
   while comment_feed is not None:  
     for comment in comment_feed.entry:  
       yield comment  
     next_link = comment_feed.GetNextLink()  
     if next_link is None:  
       comment_feed = None  
     else:  
       comment_feed = client.GetYouTubeVideoCommentFeed(next_link.href)  
   
   
   
 def search_and_store_comments(client, keyword, video_id):  
   query = "SELECT MAX(updated) FROM yt_comments WHERE keyword = %s AND video_id = %s"  
   cursor.execute(query, (keyword, video_id))  
   result = cursor.fetchone()  
   if len(result) > 0:  
     last_update = result[0]  
   if last_update is None:  
     last_update = '0'  
   if last_update == '':  
     last_update = '0'  
   for comment in comments_generator(client, video_id):  
     author_name = comment.author[0].name.text.strip()  
     text = comment.content.text.strip()  
     update_time = comment.updated.text.strip()  
     update_time = since_epoch(update_time)  
     if update_time <= int(last_update):  
       break  
     print (keyword, video_id, author_name, text, update_time)  
     try:  
       cursor.execute("INSERT INTO yt_comments (keyword, video_id, author, text, updated) VALUES (%s, %s, %s, %s, %s)", (keyword, video_id, author_name, text, update_time))  
     except psycopg2.DatabaseError, e:  
       print 'Error %s' % e  
     
   
   
   
 def search_yt(keyword):  
   client = gdata.youtube.service.YouTubeService()  
     
   vid_pat = re.compile(r'videos/(.*?)/comments')  
   vid_list = []  
   
   for start_index in range(1, 1000, 50):  
     query = gdata.youtube.service.YouTubeVideoQuery()  
     query.vq = keyword  
     query.max_results = 50  
     query.start_index = start_index  
     query.orderby = 'relevance'  
     print start_index  
     feed = client.YouTubeQuery(query)  
       
     if len(feed.entry) == 0:  
       break  
   
     for entry in feed.entry:  
       if entry.comments is None:  
         continue  
       comment_url = entry.comments.feed_link[0].href            
       result = re.findall(vid_pat, comment_url)  
       if len(result) > 0:  
         video_id = result[0]  
       else:  
         continue  
       if video_id not in vid_list:  
         vid_list.append(video_id)   
       print video_id  
         
     time.sleep(1)  
         
   vid_list = list(set(vid_list))  
   for vid in vid_list:  
     search_and_store_comments(client, keyword, vid)  
   
   
     
 def main():  
   query = "SELECT keyword FROM yt_keywords"  
   cursor.execute(query)  
   result = cursor.fetchall()  
   for item in result:  
     keyword = item[0]  
     print "Searching for keyword:", keyword  
     search_yt(keyword)  
     time.sleep(1)  
       
     
     
 if __name__ == "__main__" :  
   main()  
   print "done"