[Question] Enable an extractor at runtime for embedded youtube-dl

[C0D3D3V]

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Question

I use youtube-dl in one of my projects (moodle-dl). I can understand that with so many PR requests and so few team members, it can take a long time until an extractor gets merged.

I wonder if I can simply add extractors in an embedded youtube-dl instance externally?
For example, if I want to add the Extractor for zoom.us (#24751) at runtime, is that possible?

[dstftw]

Read developer instructions.

[C0D3D3V]

If someone tries to do the same, I suppose it works like this:

ydl.add_info_extractor(YourExternalExtractor(ydl))

[C0D3D3V]

Nope, this does not work, because Generic Extractor will raise an error as soon as it is tested... Generic Extractor is last in the Extractor list so you have to add your external extractor before the generic one, like this:

    additional_extractors = [
        OpencastIE(ydl),
        OpencastPlaylistIE(ydl),
    ]

    for extractor in additional_extractors:
        ydl._ies.insert(0, extractor)
        ydl._ies_instances[extractor.ie_key()] = extractor