How to read audio data from a 'MediaStream' object in a C++ addon

Solution 1:

The MediaStream header is part of Blink's renderer modules, and it's not obvious to me how you could retrieve this from nan plugin.

So, instead let's look at what you do have, namely a v8::Object. I believe that v8::Object exposes all the functionality you need, it has:

• GetPropertyNames()
• Get(context, index)
• Set(context, key, value)
• Has(context, key)

Unless you really need a strictly defined interface, why not avoid the issue altogether and just use the dynamic type that you already have?

For getting audio data out specifically, you would need to call getAudioTracks() on the v8::Object, which probably looks something like this?

Note: I don't think you need a context, v8 seems to be happy with it being empty: v8/src/api/api.cc

Should look something like this, plus some massaging of types in and out of v8.

v8::MaybeLocal<v8::Value> get_audio_tracks = mediaStream->Get("getAudioTracks");
// Maybe needs to be v8::Object or array?
if (!get_audio_tracks.IsEmpty()) {
    v8::Local<v8::Value> audio_tracks = get_audio_tracks.ToLocalChecked()();
}