Simple CMS as Anwiki replacement

sitescripts/web/bin/generate_static_pages.py

 # coding: utf-8
 
 # This file is part of the Adblock Plus web scripts,
 # Copyright (C) 2006-2013 Eyeo GmbH
 #
 # Adblock Plus is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 3 as
 # published by the Free Software Foundation.
 #
 # Adblock Plus is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
 
-import sys, os, re, codecs
-from ...utils import setupStderr
+import sys, os, re, errno, codecs
+from ...utils import setupStderr, cached
 from ..utils import process_page
 from ..sources import MercurialSource
 
 def generate_pages(repo, output_dir):
   known_files = set()
 
   def write_file(path_parts, contents, binary=False):
     encoding = None if binary else "utf-8"
     outfile = os.path.join(output_dir, *path_parts)
     if outfile in known_files:
       print >>sys.stderr, "Warning: File %s has multiple sources" % outfile
       return
     known_files.add(outfile)
 
     if os.path.exists(outfile):
       with codecs.open(outfile, "rb", encoding=encoding) as handle:
         if handle.read() == contents:
           return
 
     try:
       os.makedirs(os.path.dirname(outfile))
-    except OSError:
-      pass

[Sebastian Noack, 2013/10/29 11:04:17]

I would check if we got EEXIST here and only then fail silently and otherwise
re-raise the error. Otherwise for example when you don't have permissions to
create the directory, the code below will fail because of the directory doesn't
exist, which is misleading.

try:
  os.makedirs(os.path.dirname(outfile))
except OSError, e:
  if e.errno != errno.EEXIST:
    raise

+    except OSError, e:
+      if e.errno != errno.EEXIST:
+        raise
 
     with codecs.open(outfile, "wb", encoding=encoding) as handle:
       handle.write(contents)
 
   with MercurialSource(repo) as source:
+    # Cache the result for some functions - we can assume here that the data
+    # never changes
+    source.resolve_link = cached(float("Infinity"))(source.resolve_link)
+    source.read_config = cached(float("Infinity"))(source.read_config)
+    source.read_template = cached(float("Infinity"))(source.read_template)
+    source.read_locale = cached(float("Infinity"))(source.read_locale)
+    source.read_include = cached(float("Infinity"))(source.read_include)
+
     locales = list(source.list_locales())
     for page, format in source.list_pages():
       for locale in locales:
         if source.has_locale(locale, page):
           pagedata = process_page(source, locale, page, format)
 
           # Make sure links to static files are versioned
           pagedata = re.sub(r'(<script\s[^<>]*\bsrc="/[^"<>]+)', r"\1?%s" % source.version, pagedata)

[Sebastian Noack, 2013/10/29 11:04:17]

When you inject text into regular expressions always use re.escape().

[Wladimir Palant, 2013/11/04 09:49:21]

I'm not injecting into a regular expression here, it's the replacement term.
Using re.escape() can be fatal here, consider the following:

    re.sub("(a)", r"\1%s" % re.escape("$"), "abcd")

Given that source.version is known to be alphanumerical we can skip escaping
here. I've fixed this in a some other places however.

[Sebastian Noack, 2013/11/04 13:28:18]

Yes, you are right.

           pagedata = re.sub(r'(<link\s[^<>]*\bhref="/[^"<>]+)', r"\1?%s" % source.version, pagedata)
           pagedata = re.sub(r'(<img\s[^<>]*\bsrc="/[^"<>]+)', r"\1?%s" % source.version, pagedata)
 
           write_file([locale] + page.split("/"), pagedata)
 
     for filename in source.list_localizable_files():
       for locale in locales:
         if source.has_localizable_file(locale, filename):
           filedata = source.read_localizable_file(locale, filename)
           write_file([locale] + filename.split("/"), filedata, binary=True)
 
     for filename in source.list_static():
       write_file(filename.split("/"), source.read_static(filename), binary=True)
 
   def remove_unknown(dir):
     files = os.listdir(dir)
     for filename in files:
       path = os.path.join(dir, filename)
       if os.path.isfile(path) and path not in known_files:
         os.remove(path)
       elif os.path.isdir(path):
         remove_unknown(path)
         if not os.listdir(path):
           os.rmdir(path)

[Sebastian Noack, 2013/10/29 11:04:17]

You might want to remove directories recursively. So that when a/b/c.html is
removed and there aren't any other files within a will be removed too, instead
of removing only a/b.

[Wladimir Palant, 2013/11/04 09:49:21]

We are already removing directories recursively. remove_unknown("foo/a/b") will
remove foo/a/b/c.html and then return to remove_unknown("foo/a") that will
remove foo/a/b as an empty directory. It will then return to
remove_unknown("foo") which will remove foo/a. The top-level directory is never
removed which is intended.

[Sebastian Noack, 2013/11/04 13:28:18]

You are right.

   remove_unknown(output_dir)
 
 if __name__ == "__main__":
   setupStderr()
   if len(sys.argv) < 3:
     print >>sys.stderr, "Usage: %s source_repository output_dir" % sys.argv[0]
     sys.exit(1)
 
   repo, output_dir = sys.argv[1:3]
   generate_pages(repo, output_dir)