MediaEntry now has a good new generate_slug. Collection still has the old one. And we don't want to copy it over, so we should refactor this.

Well, all of this has happened in a local branch. I just need to clean it up and fix some bugs. This bug is mainly to not forget about it.

./bin/gmg theme assetlink gives me this error :

  File "./bin/gmg", line 9, in <module>
    load_entry_point('mediagoblin==0.3.3.dev', 'console_scripts', 'gmg')()
  File "/var/www/mediagoblin/mediagoblin/gmg_commands/__init__.py", line 100, in main_cli
    args.func(args)
  File "/var/www/mediagoblin/mediagoblin/gmg_commands/theme.py", line 122, in theme
    SUBCOMMANDS[args.subcommand](args)
  File "/var/www/mediagoblin/mediagoblin/gmg_commands/theme.py", line 104, in assetlink_command
    link_assets(current_theme, app_config['theme_linked_assets_dir'])
  File "/var/www/mediagoblin/mediagoblin/gmg_commands/theme.py", line 71, in link_assets
    printer(_("No asset directory for this theme\n"))
  File "/var/www/mediagoblin/mediagoblin/tools/translate.py", line 122, in pass_to_ugettext
    return mg_globals.thread_scope.translations.ugettext(
AttributeError: 'NoneType' object has no attribute 'ugettext'

Hi!

When I was looking at the attachments source code I have seen code like this:

with file:

file.write(another_file.read())

This is dangerous because you read another_file into memory completely and this can lead to MemoryErrors. There is a function shutil.copyfileobj that already does what we need: reading chunk for chunk into memory and writing it to another file object.