Crawler backend

sitescripts/crawler/bin/extract_crawler_sites.py

 # coding: utf-8
 
 # This Source Code is subject to the terms of the Mozilla Public License
 # version 2.0 (the "License"). You can obtain a copy of the License at
 # http://mozilla.org/MPL/2.0/.
 
 import MySQLdb, os, re, subprocess
 from sitescripts.utils import get_config
 
 def hg(args):
   return subprocess.Popen(["hg"] + args, stdout = subprocess.PIPE)
 
 def extract_urls(filter_list_dir):
   os.chdir(filter_list_dir)
   process = hg(["log", "--template", "{desc}\n"])
   urls = set([])
 
   for line in process.stdout:
-    matches = re.match(r".*\b(https?://\S*)", line)

[Wladimir Palant, 2012/09/27 07:34:17]

Please use re.search() rather than re.match() here (and then without .* at the
start). re.match() will always match the complete string - we are actually
interested in a substring.

Generally, I consider re.match() in Python's standard library a bug - it's
confusing and typically useless.

Side-note: I would probably name the result variable match and not matches - it
is really only one match unlike when calling re.findall().

[Felix Dahlke, 2012/09/27 09:26:24]

Done. You're right, I'm used to calling it "matches" because it's an array with
the matched string and all groups in JS. It's really just one though.

-    if not matches:
+    match = re.search(r"\b(https?://\S*)", line)
+    if not match:
       continue
 
-    url = matches.group(1).strip()
+    url = match.group(1).strip()
     urls.add(url)
 
   return urls
 
 def print_statements(urls):
   for url in urls:
     escaped_url = MySQLdb.escape_string(url)
     print "INSERT INTO crawler_sites (url) VALUES ('" + escaped_url + "');"
 
 if __name__ == "__main__":
   filter_list_dir = get_config().get("crawler", "filter_list_repository")
   urls = extract_urls(filter_list_dir)
   print_statements(urls)