Document mediaserver integration

[selfhoster1312]

There's a matterbridge component to use a dedicated mediaserver to upload files which don't have a URL.

We have helper methods in bridge/helper/helper.go called HandleDownloadData and HandleDownloadData2. It's not documented what's the difference between those two methods. One takes an additional id param, but it's not exactly clear what this NativeId is supposed to be (is it for dedup?).

It's also not documented what happens depending on whether the bridge receiving the attachment populates the Data field (raw bytes), the Url field (remote content) or both.

[poVoq]

There is some basic documentation here: https://github.com/matterbridge-org/matterbridge/blob/master/docs/advanced/mediaserver.md or are you talking about something else?

I would assume that only in the IRC bridge there is something left from it, but the Matrix bridge also needs something to upload media, as the links themselves are now authenticated and do not work over bridges.

[poVoq]

I set this up following the documentation in the above link and it is working fine.

I guess we could add an extra note about this: #51 and maybe include an example for Nginx, but otherwise it seems pretty complete?

What else were you thinking about that needs to be documented?

[selfhoster1312]

So apparently the caddy plugin documented does not work in the same way anymore (uses HTTP forms and not PUT requests) so our documentation is broken. I don't know of an alternative so my favorite approach right now is:

• deprecate MediaServerUpload
• document MediaDownloadPath better
• merge a more generic interface to implement more backends (such as S3 Implemented S3 client for mediaserver #39 #52)
• encourage people if they were using MediaServerUpload successfully (how??) to document how it works and reimplement the logic wit hthe new interface

[poVoq]

This seems done.