Okay so, for my tests, I have a few fedi instances on which gallery-dl fails to download:

• 5 Akkoma
• 2 Pleroma
• 2 Sharkey
• 3 GoToSocial
• 3 Iceshrimp

Now I need to check if the reason they fail is that they reject public access.

So, for each category:

• Akkoma / Pleroma / GTS
  => All of them work without any issue in web browser, so I suppose gallery-dl simply doesn't have the required extractor.

• Sharkey
  => Seems like all the problematic links don't work in browser, only in another fedi instance. So it's not a gallery-dl issue

• Iceshrimp
  => I have no dirting idea of what happens. One of them works in browser, a second works partially, one last doesn't. All work in another fedi instance.

Conclusion: gallery-dl may be missing required API for Akkoma/Pleroma/GTS, and fails on instances which disabled public view. No idea what iceshrimp does tho.

Okay, my conclusions so far:

• Akkoma/Pleroma URLs with "notice" can be passed directly as a regular mastodon url to gallery-dl and require a simple regex modification
• Akkoma/Pleroma URLs with "objects" seem to not work with that API, but attempting to curl them will redirect to the "notice" URL so perhaps there's an API endpoint to convert it?
• GTS: All of them seem to require some kind of token, I didn't look at the documentation yet but this might be an issue...

Okay so GTS documentation 1 indicates that all API requests require an authentication token, which requires the user to register an app and do some oauth authentication...
... and then it requires a client registered on the instance.

What?!

So you can't do any API request on GTS without having a user account on the target instance?

??!?

@Soblow yup

but i like this :3

@awoo How does federation work in that case?!