How to pass a list of allowed services to youtube-dl?

I want youtube-dl to be able to download content only from a list of allowed services. Like ['youtube','twitch'].

Also is there any way to set custom error messages?

Solution

You can monkeypatch the youtube_dl.extractor._ALL_CLASSES, so youtube_dl will not know any other extractors than you specified.

import youtube_dl

def get_list_of_extractors(extractor_modules):
    extractors = []
    for module in extractor_modules:
        list_of_extractors = [
            getattr(module, name) for name in dir(module) 
            if name.endswith('IE') and name != 'GenericIE' and name.find("Base") == -1
        ]
        extractors = extractors + list_of_extractors
    return extractors

list_of_extractors = get_list_of_extractors([youtube_dl.extractor.youtube, youtube_dl.extractor.tiktok])
youtube_dl.extractor._ALL_CLASSES = list_of_extractors

ydl = youtube_dl.YoutubeDL({})

ydl.extract_info(
    'https://www.youtube.com/watch?v=BaW_jenozKc',
    download=False # We do not need to download
)

# causes youtube_dl.utils.DownloadError, because instagram extractor is not in the list
ydl.extract_info(
    'https://instagram.com/p/aye83DjauH',
    download=False # We do not need to download
)