Do not fetch link cards for mentioned users

[ClearlyClaire]

No description provided.

[Gargron]

I don't like the idea of making a hacky solution even more hacky but also forcing all app developers to make this subtle adjustment. How about we process the HTML server-side and replace the URI with URL when applicable?

To be honest if we start doing server-side processing of that HTML, we're only a few steps away from parsing the HTML into plaintext with demarkated entities...

[ClearlyClaire]

@Gargron I don't like the idea of rewriting HTML links because you're really rewriting links, as opposed to just adding handlers dynamically in the WebUI. If the URL and URI are different for a reason, this breaks the original status' meaning in some way.

[Gargron]

Well... There is a reason the URL property exists in the first place, it's what should be linked to. Imagine an AP implementation that returns only JSON-LD from the id URI. What would be the point of linking to it in HTML that end-users are supposed to see? And if the HTML is not meant for end-users, then post-processing it server-side on our end is exactly in line with that, because we intend the HTML to be for end-users...

[ClearlyClaire]

Yes I know, but hear me out: admittedly, that is an edge case, but what if I purposefully link to that JSON-LD-only URL in my toot, for instance to talk about some ActivityPub software? I wouldn't want that link to be rewritten in my back, that would be extremely confusing.

[MightyPork]

is this the reason some foreign statuses show the user profile as an embed?

[ClearlyClaire]

@MightyPork that's probably addressed by the last commit, yeah

[Gargron]

@MightyPork Mastodon uses microformats rel="mention" to demarkate mention links and conversely skip them when fetching link previews. Other platforms don't do that so their mention links look just like any other links.

[nightpool]

can we make a compromise here, and write in an explicit data-mention-acct="id" attribute?

…

On Thu, Mar 29, 2018, 12:42 PM Eugen Rochko ***@***.***> wrote: @MightyPork <https://github.com/MightyPork> Mastodon uses microformats rel="mention" to demarkate mention links and conversely skip them when fetching link previews. Other platforms don't do that so their mention links look just like any other links. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#6934 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAORVyPBXdWYlIOkyDHXFKFDWCe0lWsqks5tjQ8QgaJpZM4S9SSt> .

[ClearlyClaire]

@Gargron actually, Mastodon uses CSS classes “u-url” and “mention”, and skips prefetching for links with a class of “u-url”.

@nightpool why not, but that's yet another thing to specify and push to other implementors of the fediverse…

[nightpool]

Why would it have anything to do with other implementors in the fediverse? I'm just talking about for mastodon's API retrieval.

[nightpool]

I'm not necessarily against this PR, it just seems like if we want a more stable solution, explicitly specifying the account id server-side before sending it to the client is the most robust and easy to implement one.

so something like <a href="whatever" data-mention-acct="899">@nightpool</a>

[ClearlyClaire]

Ah ok, I thought you were talking about specifying the markup of the toot itself, and not something returned from the API.
I'm not sure how much I like it, but it makes sense. It's more work on the Mastodon backend side of things, and you still have to modify the clients to take advantage of it, but once it's done, if we ever do more elaborate guesswork, that could be kept to the backend.

[lambadalambda]

FYI: https://git.pleroma.social/pleroma/pleroma/commit/806550c921d1137e47ec662ea83ee0a542fb55d5

[lambadalambda]

btw, about that rel=mention, i didn't find it in the html the mastodon api returns, just class=mention. Where exactly are you using it?

[Gargron]

btw, about that rel=mention

I got confused in my memory. It's rel=tag for hashtags, and class=u-url for mentions. rel=mention would have been consistent with rel=tag, but from a cursory google search, that does not seem to be a thing anywhere. rel=tag is indeed microformats.

[lambadalambda]

would it make sense for me to add that? where does the u-url come from?

[Gargron]

@lambadalambda The u-url comes from hcard (microformats), see full markup: https://github.com/tootsuite/mastodon/blob/master/app/lib/formatter.rb#L226

I like @nightpool's suggestion with data-mention-account. I think the sanitizer strips out such attributes from remote HTML so it should be fine for clients to expect it to be valid & local.

[Gargron]

Did this get adjusted on Pleroma's side? I would prefer to avoid these changes if possible.

[ClearlyClaire]

Yeah, pleroma has been changed to play nice with Mastodon afaict. However, the preview card fetching code will still try to fetch mentioned users.

[ClearlyClaire]

Updated to simply stop Mastodon from fetching cards for mentioned users