Subtitles

[pacoccino]

I propose this code changes to enable subtitles downloading.
It is the first time for me using python&django so it’s a bit of discovery ;)

I don’t know if I’ve done everything that would have been necessary to add this feature, but it does what I need as it is.

I worked on this as I really need to have subtitles downloaded and I don’t need/want something as heavy as tubearchivist.

#7 #367

[meeb]

Thanks for the contribution! This looks fine to me. The only thing I would suggest is some model form validation as a Django validator that confirms that the subtitle language field is actually a comma-separated array of two letter, lower case values. Currently as far as I can see this will otherwise let people pass arbitrary data to yt-dlp's API which is probably worth putting some guide rails on.

Something like (untested, just typed ad-hoc):

def validate_is_subtitle_lang_list(value):
    parts = value.split(',')
    if not parts:
        return True
    subtitle_lang_chars = 'abcdefghijklmnopqrstuvwxyz'
    for i, lang in enumerate(parts):
        if len(lang) != 2:
            raise ValidationError(f'Subtitle lang code at position {i} is {len(lang)} chars, must be 2 chars')
        for c in lang:
            if c not in subtitle_lang_chars:
                raise ValidationError(f'Subtitle lang code at position {i} must be a-z lowercase only, got {lang}')
    return True

As you're new to Django, here's how validators are integrated to save you looking it up: https://docs.djangoproject.com/en/4.2/ref/validators/ - you can add the validator to your new sub_langs field. Thanks again for the PR, most appreciated.

[pacoccino]

Nice catch, I added a validator, but opted for a regex instead, matches better the options available

Another thing is that it won't download subtitle for already downloaded videos, I doubt you can use yt-dlp just for downloading subtitle without video but I'll check that

[meeb]

Nice, thanks! I'll give this a test and merge it into the next release.

[tehniemer]

Will this grab subtitles for already downloaded media?

[meeb]

Alas, no it won't.