How to extend app.bsky.feed.post?

[bamnet]

tl; dr: What's the right way to extend app.bsky.feed.post with additional information from a custom lexicon?

Reading the Custom Schema documentation, it sounds like this should be accomplished through the embed property which is an open union.

What's the right way to accomplish that?

Is it as easy as creating a copy of app/bsky/feed/post.json and modifying embed to include my custom lexicon, or is there a way for me to extend the existing lexicon without having to maintain my own copy of it. As the official lexicon evolves, I'm worried a locally modified copy will drift out of sync (and I only want to add an embed).

[yamarten]

To use a new type in an open union field, simply define a new object type in your NSID, as bsky does. The union's specifications allow you to use it without expanding post. Of course, if the client does not know the type, the embedding will be ignored.

However, when using a new type, it is not essential to create a lexicon. The main advantage of making it is that PSD can validate the contents of the field, but at this time, the implementation of lexicon resolution has not been completed, so it will not be obtained either way.

[danielmcquillen]

@yamarten What if your custom lexicon includes information that needs a special UI to render?

Is the idea to somehow point the user to a different custom web client that has the feature set that can render that content?

Let's say you define a custom lexicon called app.example.special.content and it defines things like title and description but then some more interesting content (e.g. a poll, a mini data table, maybe some data content that needs a special web component, etc.)

To author content, you'd need that custom web app to provide the author with a UI to create and post that content and place it on the AT Network.

But then to view it, a viewer on Bluesky could see just the post -- just the title? -- and then they would have access to it through the embed property, right?

How would Bluesky know how to indicate to the user that they would need to go to a special custom web client to view it (through a URL to that web app)? Would there be any kind of SSO possible for a seamless experience?

Sorry if I'm mangling all this. I'm in the same spot as @bamnet is, I think, just trying to get my head around how one might overload the basic post to include interesting content ).

[bamnet]

@danielmcquillen AFAICT there's no answer to the UI questions. Plugin support touches on some strategies they could consider, but it's still early days.

Until there's the ability to customize the UI, I'm planning on including enough text content to make each post meaningful for people who can't see my embedded data (aka everyone right now) and including a URL in each post (app.bsky.richtext.facet#link) which links to a web-app that is capable of rendering the embedded data correctly. I haven't gotten this working yet, but happy to share a demo when I have!

[danielmcquillen]

Yes, please! Don't understand AT protocol enough to see how this would all work so any info from your own experiments would be awesome thanks.

But if I understand you correctly: If a Bluesky user sees a post that happens to include some of your custom data, and sees in that post a little embed block with whatever content, and has access to that link (via app.bsky.richtext.facet#link), they click that to go to your-special-app.com and then they just have to sign in again to view it (with your site remembering and respecting the route after authentication). I assume any further clicks in same browser on other Bluesky embeds should not need another sign in, via persisted session cookie from your site.