We have a process that runs on a regular frequency to look for livestreams that have been started for the authenticated channel, and to start a chat watcher once such a livestream is detected. We would like to extend this to gather the same for any channel owned by owner of the authenticated account. (We wouldn't mind providig a list of channels of interest...) It is no problem for another channel's chat to be "watched" by the authenticated account since the livestreams we're talking about (and their chats) are public and open. We do this manually all the time. Ideally, we would be able to provide a channel list to this API, but alas, there seems to be no such parameter.
The API documentation for the YouTube Livestream List API at https://developers.google.com/youtube/v3/live/docs/liveBroadcasts is not clear about how to request information about another channel (other than the one that is authenticated). (There is also the "By ID" option, but that does not fit this purpose.) Testing seems to indicate that all requests to this API (other than By ID) return only information about the authenticated channel, and yet there is a "mine" parameter that will limit to only the authenticated channel. But why would there be a Mine parameter if the results are limited to Mine anyway? So based on the testing results, I am confused about the purpose of the Mine parameter, and I remain hopeful that there is a way (other than blind search) to return livestreams for all channels owned by the authenticated account.
The "on behalf of" parameter is sort of what we're looking for, but of course (as clearly stated) that's for a different class of YouTube customer. And besides, that is also not a list of channels - it is one only.
Is there an API or approach that we can use other than blind search that will return to us all the livestreams associated with the authenticated account? While Search with appropriate parameters will return the desired information, that information doesn't seem to be limitable to particular channels (except, again, limiting to the authenticated channel), so a lot of information is returned for channels that are "colateral" to the sought data, and it's a chore requiring extra procesing time, memory, and API calls (for next page, etc) to pore through that, looking for the channels of interest.
Maybe we're using the wrong API? Maybe we don't know how to massage/coerce the parameter list? Or would we be required to create an authentication for each channel even though we techincally don't need that authentication (except for the List Livestreamms API)?