[Mastodon] Use ActivityPub outbox for Mastodon (et al.) feed

[austinhuang0131]

Closes #2754.

In theory this supports all ActivityPub-compatible software¹. This may warrant renaming the bridge (not included in PR).

Example: https://rssbridge.bus-hit.me/?action=display&bridge=Mastodon&canusername=%40austin%40ieji.de&format=Html

Footnotes

1. I have tested it on Pleroma and Misskey instances. AFAIK it supports certain Pixelfed instances, but the official one has ActivityPub outbox disabled. ↩

[github-actions]

Pull request artifacts

file	last change
Mastodon-current-context1	2022-06-20, 21:38:51
Mastodon-pr-context1	2022-06-20, 21:38:51

[yamanq]

Thanks for this fast work! I will be able to review this in more detail in about a week or two. For now, I noticed a few things:

• I think it would be fine to rename this to ActivityPubBridge and then have the Mastodon bridge inherit that class with minimal changes (NAME, DESCRIPTION) for compatibility with existing feeds.
• boosts that fail to getContents are hidden from the feed. Could you instead create an item like this (not sure if I'm using the right terminology):
  title: Shared an unreachable status
  content: link to original status:
• Could you add a note in the title text of the "Without Boosts" checkbox that this may connect to other federated instances that are boosted by the user?
• There is this notice in the content: Notice: Undefined index: mediaType in /app/bridges/MastodonBridge.php on line 128
  

[austinhuang0131]

I will wait till there is a consensus on renaming it. But wouldn't inheriting it add two duplicating feeds?

[dvikan]

I refactored a bit. Don't use catch (Throwable), be more specific. Or check return values. I think it's fine to merge this.
In the future, please create a separate activitypub/webfinger client. I prefer we don't do inheritance.

[austinhuang0131]

@dvikan To be honest I'd also prefer for it to be a separate bridge. The current client should be stripped of its options. So if we're on the same page on this then I'll rename the files a bit.

[yamanq]

In that case, What about changing the NAME while keeping the file and class name as MastodonBridge to maintain backwards compatability? I am against changing the class name but I am fine if inheritance is not used.

[dvikan]

I suggest to follow yamanq's advice.

[yamanq]

Great work!

[austinhuang0131]

I have added a change to support instances with Secure Mode. This requires some setup by the host (which requires another PR to the docs), which can be summarized as:

1. Get a RSA keypair
2. Put up a static webfinger page, eg. https://rssbridge.bus-hit.me/.well-known/webfinger
3. Put up a static actor page with your public key, eg. https://rssbridge.bus-hit.me/actor
4. Let RSS-Bridge know your private key, and your public key ID, in config

For examples, try @admin@bgme.me or @admin@c.im

See also https://blog.joinmastodon.org/2018/06/how-to-implement-a-basic-activitypub-server/

[yamanq]

LGTM, please add those instructions to securing a token into the Bridge Specific section of the docs. Also, mention that this bridge can be configured in the DESCRIPTION.

To satisfy the linter, you can just create a newline without closing the string:

 	const DESCRIPTION = 'Returns recent statuses. Supports Mastodon, Pleroma and Misskey, among others.
Some Mastodon instances use Secure Mode which ...';

[yamanq]

Thanks for all your work on this!