if os.environ.get('SERVER_SOFTWARE','').startswith('Dev'):
    from google.appengine.tools.dev_appserver import FakeFile
    FakeFile.ALLOWED_MODES = frozenset(['a','r', 'w', 'rb', 'U', 'rU'])

The problem here is that you need an environment variable with your app id, which you can set with the following code:

os.environ['APPLICATION_ID'] = 'myapp'

After you do that you’ll get this error:

To fix that one you need the following lines in your test setup:

datastore_file = '/dev/null'
from google.appengine.api import apiproxy_stub_map,datastore_file_stub
apiproxy_stub_map.apiproxy = apiproxy_stub_map.APIProxyStubMap()
stub = datastore_file_stub.DatastoreFileStub('myapp', datastore_file, '/')
apiproxy_stub_map.apiproxy.RegisterStub('datastore_v3', stub)

This temp datastore is persisted just while you run your tests. But you can also give the datastore_file variable a real filename and then it will save the datastore between tests, or you could create different datastore files for different scenarios.

Finally, to put it all together, here is the setUp method for my TestCase classes:

class SomeTestCase(unittest.TestCase):
	def setUp(self):
		app_id = 'myapp'
		os.environ['APPLICATION_ID'] = app_id
		datastore_file = '/dev/null'
		from google.appengine.api import apiproxy_stub_map,datastore_file_stub
		apiproxy_stub_map.apiproxy = apiproxy_stub_map.APIProxyStubMap()
		stub = datastore_file_stub.DatastoreFileStub(app_id, datastore_file, '/')
		apiproxy_stub_map.apiproxy.RegisterStub('datastore_v3', stub)

00:20:24,345 --> 00:20:25,200
Hello there.
How are you?

So I created a little script, suboffset.py, which takes in the name of a subtitle file and the offset to add to the file in milliseconds, modifies the file contents and writes it back out to the same file. Alternately you can specify – as the filename and then the script will read the file from stdin and write the output to stdout so you can pipe it together to write to another file. The original script was about 10 lines, but just to make it a little more useful I made it a module so you could get access to the script from other scripts and added the stdin option and some comments. You can view the script below or download the actual script here.

#!/usr/bin/python
"""
   Script to offset the time in subtitle files in the .srt format. Script
   takes in the filename and the offset (in milliseconds) to add or
   subtract from the subtitles. It then writes the new subtitles to the
   same file. Alternately you can specify the filename as '-' and then
   the script will read input from stdin and write output to stdout.

"""

__version__   = '1.0'
__author__    = 'Einar Egilsson'
__date__      = 'March 20th 2008'
__url__       = 'http://einaregilsson.com/2008/03/20/subtitle-fixer/' 

import sys, re, datetime

MILLISECOND = 1
SECOND = 1000 * MILLISECOND
MINUTE = 60 * SECOND
HOUR = 60 * MINUTE

def offset_time(time, offset):
    """ Takes in list with [hour, minute, second, millisecond] and returns
        it with offset milliseconds added and normalized
    """
    ms = sum(map(int.__mul__,  time, [HOUR, MINUTE, SECOND, MILLISECOND]))
    ms += offset
    return [ms / HOUR, ms % HOUR / MINUTE, ms % MINUTE / SECOND, ms % SECOND]

def fix_subtitles(lines, offset, output):
    """ Takes in list (lines) with all the lines from the subtitle file, adds
        offset milliseconds to it and writes the file to output.
    """
    for line in lines:
        pattern = r'(\d\d):(\d\d):(\d\d),(\d\d\d) --> (\d\d):(\d\d):(\d\d),(\d\d\d)'
        match = re.match(pattern, line)
        if match:
            nrs = [int(nr) for nr in match.groups(0)]
            start = offset_time(nrs[:4], offset)
            end = offset_time(nrs[4:], offset)
            output.write('%02d:%02d:%02d,%03d' % tuple(start))
            output.write(' --> ')
            output.write('%02d:%02d:%02d,%03d\n' % tuple(end))
        else:
            output.write(line)

def print_header():
    print 'Subtitle Fixer v%s' % __version__
    print 'Author: %s' % __author__
    print __url__
    print ''

if __name__ == '__main__':
    if len(sys.argv) != 3:
        print_header()
        print 'Usage: suboffset.py <filename> <offset-in-milliseconds>'
        print 'Use - for filename to read from stdin and print to stdout'
        sys.exit(1)

    offset = int(sys.argv[2])
    file = None
    if sys.argv[1] == '-': #Read from stdin and print to stdout
        fix_subtitles(sys.stdin.readlines(), offset, sys.stdout)
    else: #read from file and write to same file
        file = open(sys.argv[1], 'r')
        lines = file.readlines()
        file.close()
        file = open(sys.argv[1], 'w')
        fix_subtitles(lines, offset, file)
        file.close()
        print 'Finished adding %s milliseconds to %s' % (offset, sys.argv[1])

The script logs into your Haloscan account, makes a http request for each comment and writes them to an .xml file. If the script fails halfway through you can just start it again and it will continue where it left off. A xml file with the name yourusername.xml will be created in your working folder where you start the script. It contains all information about every comment, date, author, url, email, ip, threadid, commentid and text. You can then parse the xml file to import them into other comment systems. Before you download the script, be sure to read the following disclaimer:

DISCLAIMER: This is provided “AS-IS”, I make no guarantees that this works, it’s based on screen scraping so could stop working whenever Haloscan change their pages.

This script makes a new http request for every single comment so if you have thousands of comments and Haloscan doesn’t approve of you pounding their server and suspends your account and you lose all your comments, I CANNOT BE HELD RESPONSIBLE. USE AT YOUR OWN RISK! You’ve been warned!

Now that you’ve read that, you can download the script here or view it syntax highlighted here.

When the script is run the output will look something like this:

Mozilla Extension Generator
Copyright (c) 2007 Einar Egilsson (http://einaregilsson.com)

Extension name: My New Extension
Extension code name: MyNewExtension
Extension description: Does this and that
Firefox or Thunderbird (f/t) : f
Include Menu item ? (y/n): y
Include Context menu ? (y/n): y
Author name: Einar Egilsson
Guid: mynewextension@einaregilsson.com
Menu item label: My New MenuItem
Menu item access key: m
Contextmenu item label: My New ContextItem
Contextmenu item access key: c

Creating files...

mynewextension/install.rdf
mynewextension/chrome.manifest
mynewextension/defaults/preferences/mynewextension.js
mynewextension/chrome/content/mynewextension.js
mynewextension/chrome/content/overlay.xul
mynewextension/chrome/skin/overlay.css
mynewextension/chrome/content/mynewextension.png
mynewextension/chrome/content/mynewextensionlib.js
mynewextension/chrome/locale/en-US/mynewextension.dtd
mynewextension/chrome/locale/en-US/mynewextension.properties

Extension complete

This will generate all the necessary files for the extension, you can simply go into the folder created, zip it up, name as .xpi and install the extension. The questions are pretty straight forward, just about the only thing you need to know is that Extension code name must be a single word, because it will become a javascript object that all your other code will be wrapped in, to avoid polluting the global namespace.

Now, some features of the generated extension:

• Localization ready, strings are in .dtd and .properties files
• Includes a library file with common function like accessing your prefs, writing to a file and more.
• Includes debug functions that output to the javascript console and can be turned off in about:config
• Can include menu item and context menu commands
• …and more, just look at the generated files

The generator is a single python file that includes all the other files. It should be easy to modify for anyone with a working knowledge of python. There are a few constants at the top that you can tweak, they are:

#Constants
#Fill these out so you won't get prompted for them everytime:
YOUR_NAME       = ''
YOUR_DOMAIN     = '' # if filled out the extension guid will be of
                     #the form extensionname@yourdomain.com
FIREFOX_MIN     = '2.0'
FIREFOX_MAX     = '2.0.0.*'
THUNDERBIRD_MIN = '2.0'
THUNDERBIRD_MAX = '2.0.0.*'
INITIAL_VERSION = '0.9'

The icon file is also embedded in the file as a base64 encoded string. To replace it with your own file, create a .png image file (34×34 pixels) and run the script below (download) to create the base64 string, then copy it over the existing base64 string in the extension.py file.

import sys, base64

if len(sys.argv) == 1:
    print 'Usage: base64 <filename>'
    sys.exit(0)

b64 = base64.b64encode(open(sys.argv[1], 'rb').read())
i = 0

while i < len(b64):
    print b64[i:i+80]
    i += 80

And finally, you can download the python script here. You can also view it syntax highlighted here but don’t copy it from there as the syntax highlighting might screw something up. Enjoy