Andrew

TootSweet’s link was to a migration. A migration is used to upgrade a database’s schema - changing the limit on username length from whatever it was, to 255. As it happens, it’s still 255 now, but an upgrade from 3 years ago isn’t a good source for that, because as they themselves said, there could very well have been been upgrades since, that further changed the limit.

I used ‘unscientific’ because it would be a pain in the arse for someone else to reproduce, it only applies to one instance, it’s a test on someone else’s in-production system that you have no control over, and the error that returns isn’t necessarily from the backend. It looks more like a Form Validation error (i.e. from the frontend). It’s perfectly possible to create a frontend that puts it’s own limits on username length, and there’s some that no doubt already exist, so a brute-force test of those limits isn’t telling you anything reliable about what Lemmy’s internal limits are.

I think the way you were using references started to wind me up. It gave some academic veneer to a format that usually more conversational. They’re just links to what some people reckon, but dressed up with ‘accessed’ and ‘published’ in a footnote format that in other other contexts would suggest a level of credibility that they don’t have. Either something is solved or it isn’t, but it shouldn’t be marked ‘solved’ with links to answers of questionable accuracy.

Is it? Maybe. If I was using software, and asked a question that the developers of it could easily answer, and they didn’t, I might think about using something else. It certainly would’ve helped though, if you’d got an answer from someone you were more ready to believe.

I think you can be an outsider to a particular system, and still be able to provide valuable information about it. Enough to be able to satisfy your own curiosity, and hopefully someone else’s too. I can imagine a version of this post where you asked what the max username length was, I gave you a means to find out, and we both went on our way. So you can be ‘right person’ to comment on a post, but the ‘wrong person’ when it turns out that your answer isn’t going to be fully accepted without digging into someone else’s source code. As for who the right person is in that case, there’s some overlap with your comment about ‘entitlement’, so I’ll continue there.

I saw your edit, yeah. I’m not some precious person who thinks no-one should dare question their claims. To my mind, though, what I said wasn’t a claim. A claim would be if I’d said “lemmy.world is 26, sh.itjustworks is 50” with no further info. Instead, I gave command-line instructions for you to run yourself, so you could get the answers for those instances (and any other instances) from Lemmy’s backend itself. If I wasn’t reasonably sure that the backend was giving you the numbers you were looking for, I wouldn’t have mentioned it.

I wasn’t reacting to being questioned, though, I was reacting to being singled-out for being questioned. You marked this as “Solved” based - also - on a test from you, and an answer from TootSweet, but it didn’t look like to me that you ever questioned whether those answers deserved a follow-up. Neither of those, in my opinion, are really good enough, but I’ll say why in the answers to your individual comments about them.

I’m not used to this level of rigour to be honest. You’ve accepted your own unscientific prodding of one particular instance as an answer, and one link to a years-old migration as a answer, but I give you reproducible command-line instructions, which match up with your own findings, and it’s apparently not good enough.

Anyway, as that migration shows, Lemmy distinguishes between ‘name’ for username, and ‘display_name’ for the display name. A better link for this is arguably https://github.com/LemmyNet/lemmy/blob/main/crates/db_schema/src/schema.rs#L735 but whatever. It’s these fields that are relevant to Lemmy’s API, not the terminology that ActivityPub uses. A client might reasonably want to know the limit for a username (as provided in the Site response), because it’s this that’s used for Signup and Login. Display name is set elsewhere, once that’s done, so it doesn’t make sense for actor_name_max_length to refer to this.

Within ActivityPub, the distinction between username and display name is ‘preferredUsername’ and ‘name’, but AP also uses ‘name’ for a bunch of other things (including but not limited to what becomes a post title, a choice in a poll, or the alt-text for an image). There’s some overlap with how Lemmy’s API refers to stuff (e.g. a post title is a post name), but it not a 1:1 match.

I hope this is enough. I don’t even use Lemmy, so - in my opinion - you’re asking the wrong question to the wrong person. What you should be asking, is - “How come when I post a question to Lemmy’s support community, on the instance owned by Lemmy devs, it looks like they just ignore it?”. You shouldn’t have to be relying on guesswork by amateurs, irrespective of how many ‘references’ they can quote.

Not much. I think Lemmy’s current API docs are generated from the JS client. So I guess there’s

https://join-lemmy.org/lemmy-js-client-docs/v0.19/interfaces/LocalSite.html#actor_name_max_length

This refers to the wrong line number though, it’s actually at:

https://github.com/LemmyNet/lemmy-js-client/blob/ad9f402e06292899a35927c46fe48b22c6f5eb27/src/types/LocalSite.ts#L59

It seems to be set per-instance - you can find out through their APIs:

curl -L http://lemmy.world/api/v3/site | jq -r .site_view.local_site.actor_name_max_length (26)

curl -L http://sh.itjust.works/api/v3/site | jq -r .site_view.local_site.actor_name_max_length (50)