I have deeply mixed feelings about #ActivityPub's adoption of JSON-LD, as someone who's spent way too long dealing with it while building #Fedify.
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@mat Has a reason, just wrote it to @julian in a DM, just didn't want to post public.
Not sure if you visited the link. This _was_ the community approval …
Immers was famous and we had some official Social CG meetings where I linked one where thousands of community people attended (?)
The W3C Social CG _is_ the Community (?)
Meanwhile even Public Spaces Incubator uses it which is to my best knowledge the largest upcoming iimplementor by far.
I mean apart from that it is pretty obvious after the meeting where we talked about "factual" vs "fictional".
mastodon has nothing to do with this. The majority of projects count in a democracy. We had a demo playing chess between 4 softwares.Doing the official AP Conf and becoming elected Policy Lead, I had always asked the community. For 20 years
https://conf.tube/c/apconf_channel/videosNot sure if anyone did read the "Conformance Section" of ActivityPub. https://www.w3.org/TR/activitypub/#conformance
It is section 2 - You have to support "The Entirety"...
If mastodon does not it is not ActivityPub. -
@mat
Just btw, this is 7 years old https://www.reddit.com/r/chess/comments/94ubnd/chess_over_activitypub/ but anywayHowever, given that I have, including immers and redaktor, at least 3 apps where I can use the first chess spec.:
if more than 2 implementations will also support this second chess specification, I will do so too. -
I have deeply mixed feelings about #ActivityPub's adoption of JSON-LD, as someone who's spent way too long dealing with it while building #Fedify.
Part of me wishes it had never happened. A lot of developers jump into ActivityPub development without really understanding JSON-LD, and honestly, can you blame them? The result is a growing number of implementations producing technically invalid JSON-LD. It works, sort of, because everyone's just pattern-matching against what Mastodon does, but it's not correct. And even developers who do take the time to understand JSON-LD often end up hardcoding their documents anyway, because proper JSON-LD processor libraries simply don't exist for many languages. No safety net, no validation, just vibes and hoping you got the
@contextright. Naturally, mistakes creep in.But then the other part of me thinks: well, we're stuck with JSON-LD now. There's no going back. So wouldn't it be nice if people actually used it properly? Process the documents, normalize them, do the compaction and expansion dance the way the spec intended. That's what Fedify does.
Here's the part that really gets to me, though. Because Fedify actually processes JSON-LD correctly, it's more likely to break when talking to implementations that produce malformed documents. From the end user's perspective, Fedify looks like the fragile one. “Why can't I follow this person?” Well, because their server is emitting garbage JSON-LD that happens to work with implementations that just treat it as a regular JSON blob. Every time I get one of these bug reports, I feel a certain injustice. Like being the only person in the group project who actually read the assignment.
To be fair, there are real practical reasons why most people don't bother with proper JSON-LD processing. Implementing a full processor is genuinely a lot of work. It leans on the entire Linked Data stack, which is bigger than most people expect going in. And the performance cost isn't trivial either. Fedify uses some tricks to keep things fast, and I'll be honest, that code isn't my proudest work.
Anyway, none of this is going anywhere. Just me grumbling into the void. If you're building an ActivityPub implementation, maybe consider using a JSON-LD processor if one's available for your language. And if you're not going to, at least test your output against implementations that do.
#JSONLD #fedidev
@hongminhee I have the same feeling. The idea behind JSON-LD is nice, but it isn't widely available, so developing with it becomes a headache: do I want to create a JSON-LD processor, spending twice the time I wanted to, or do I just consider it as JSON for now and hope someone will make a JSON-LD processor soon? Often, the answer is the latter, because it's a big task that we're not looking for when creating fedi software.
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@hongminhee take this part with a grain of salt because my benchmarks for it are with dotNetRdf which is the slowest C# implementation i know of (hence my replacement library), but JSON-LD is slower than RSA validation, which is one of the pain points around authorized fetch scalability
wetdry.world/@kopper/114678924693500011 -
@hongminhee take this part with a grain of salt because my benchmarks for it are with dotNetRdf which is the slowest C# implementation i know of (hence my replacement library), but JSON-LD is slower than RSA validation, which is one of the pain points around authorized fetch scalability
wetdry.world/@kopper/114678924693500011@hongminhee if i can give one piece of advice to devs who want to process JSON-LD: dont bother compacting. you already know the schema you output (or you're just passing through what the user gives and it doesn't matter to you), serialize directly to the compacted representation, and only run expansion on incoming data
expansion is the cheapest JSON-LD operation (since all other operations depend on it and run it internally anyhow), and this will get you all the compatibility benefits of JSON-LD with little downsides (beyond more annoying deserialization code, as you have to map the expanded representation to your internal structure which will likely be modeled after the compacted one) -
Manu, maker of JSON-LD who also helped with the AP Confs, made this nice video https://www.youtube.com/watch?v=vioCbTo3C-4
JSON-LD is a normative reference to ActivityPub. The context of AP is only 1 line, maybe 4 if you support the official extensions. It does not make anything much larger.
It is for example important if you want to consume the federated wikipedia, wikidata, European Broadcasting Union or these Public Broadcasters https://www.publicmediaalliance.org/public-broadcasters-create-public-spaces-incubator/ but also to know that e.g. mobilizon uses schema.org for addresses.
I give you an example, if you include
"mz": "https://joinmobilizon.org/ns#", "wd": "https://www.wikidata.org/wiki/Special:EntityData/",
"wdt": "https://www.wikidata.org/prop/direct/"in your context, then you know about mobilizon extension but also the whole common knowledge of the world …
I like that, now you can support the whole vocabulary of wikipedia and wikidata which is just JSON-LD.
You get it in all the languages of the world including the properties name.
No problem, if others don't support it, but sad for users. -
Manu, maker of JSON-LD who also helped with the AP Confs, made this nice video https://www.youtube.com/watch?v=vioCbTo3C-4
JSON-LD is a normative reference to ActivityPub. The context of AP is only 1 line, maybe 4 if you support the official extensions. It does not make anything much larger.
It is for example important if you want to consume the federated wikipedia, wikidata, European Broadcasting Union or these Public Broadcasters https://www.publicmediaalliance.org/public-broadcasters-create-public-spaces-incubator/ but also to know that e.g. mobilizon uses schema.org for addresses.
I give you an example, if you include
"mz": "https://joinmobilizon.org/ns#", "wd": "https://www.wikidata.org/wiki/Special:EntityData/",
"wdt": "https://www.wikidata.org/prop/direct/"in your context, then you know about mobilizon extension but also the whole common knowledge of the world …
I like that, now you can support the whole vocabulary of wikipedia and wikidata which is just JSON-LD.
You get it in all the languages of the world including the properties name.
No problem, if others don't support it, but sad for users.PS, I am using the official JSON-LD processor of Manu and contributors, if support in any language is lacking, we just speak to the JSON-LD Group (glad about the 2 webintents coming together now as well ) …
Cause we are social … -
@hongminhee if i can give one piece of advice to devs who want to process JSON-LD: dont bother compacting. you already know the schema you output (or you're just passing through what the user gives and it doesn't matter to you), serialize directly to the compacted representation, and only run expansion on incoming data
expansion is the cheapest JSON-LD operation (since all other operations depend on it and run it internally anyhow), and this will get you all the compatibility benefits of JSON-LD with little downsides (beyond more annoying deserialization code, as you have to map the expanded representation to your internal structure which will likely be modeled after the compacted one)@kopper@not-brain.d.on-t.work @hongminhee@hollo.social expansion is actually really annoying because the resulting JSON has annoyingly similar keys to lookup in a hashmap, wasting cache lines, and CPU time
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@hongminhee take this part with a grain of salt because my benchmarks for it are with dotNetRdf which is the slowest C# implementation i know of (hence my replacement library), but JSON-LD is slower than RSA validation, which is one of the pain points around authorized fetch scalability
wetdry.world/@kopper/114678924693500011@hongminhee i put this in a quote but people reading the thread may also be interested: json-ld compaction does not really save that much bandwidth over having all the namespaces explicitly written in property names if you're gzipping (and you are gzipping, right? this is json. make sure your nginx gzip_types includes ld+json and activity+json)
RE: not-brain.d.on-t.work/notes/aihftmbjpxdyb9k7 -
hm, we really need to differentiate between users responsibility and dev responsibility.
Not sure if Hong saw the draft about the AP kv thing, it supports either JSON-LD fields _or_ as:attachment / as:context …
wtf do I want to say.user story:
We are working on 2 major and 3 projects fulltime which is
- federation of wikibase / wikidata
- federation of Public Broadcasters https://www.publicmediaalliance.org/public-broadcasters-create-public-spaces-incubator/
and these https://codeberg.org/Menschys/fedi-codebaseLet's say we want to federate a Country, then all the knowledge is sent in `attachment` with the fully qualified qikidata url in `context` [as:context - not @context ! - this is so confusing :)]
For example the according entries from the PressFreedomIndex `collection` (co-founder of freelens here
But anyway, the idea about having
"wd": "https://www.wikidata.org/wiki/Special:EntityData/",
"wdt": "https://www.wikidata.org/prop/direct/" in the `@context` was that any user can consume and federate wikibase
incl.
🧵 1/2 -
hm, we really need to differentiate between users responsibility and dev responsibility.
Not sure if Hong saw the draft about the AP kv thing, it supports either JSON-LD fields _or_ as:attachment / as:context …
wtf do I want to say.user story:
We are working on 2 major and 3 projects fulltime which is
- federation of wikibase / wikidata
- federation of Public Broadcasters https://www.publicmediaalliance.org/public-broadcasters-create-public-spaces-incubator/
and these https://codeberg.org/Menschys/fedi-codebaseLet's say we want to federate a Country, then all the knowledge is sent in `attachment` with the fully qualified qikidata url in `context` [as:context - not @context ! - this is so confusing :)]
For example the according entries from the PressFreedomIndex `collection` (co-founder of freelens hereBut anyway, the idea about having
"wd": "https://www.wikidata.org/wiki/Special:EntityData/",
"wdt": "https://www.wikidata.org/prop/direct/" in the `@context` was that any user can consume and federate wikibase
incl.
🧵 1/2incl.
- the properties in all the languages of the world
- the knowledge of the world in all the languages
- the wikidata relations and qualified statements including the nameMap etc. and all the urls to all wikiprojects incl. their languages and knowledgeHow else could I say to other softwares if they want all users qualified data, use wikidata vocabulary?
wikipedia, wikidata, EBU, Public Broadcasters, taxi data is _all_ JSON-LD … -
incl.
- the properties in all the languages of the world
- the knowledge of the world in all the languages
- the wikidata relations and qualified statements including the nameMap etc. and all the urls to all wikiprojects incl. their languages and knowledgeHow else could I say to other softwares if they want all users qualified data, use wikidata vocabulary?
wikipedia, wikidata, EBU, Public Broadcasters, taxi data is _all_ JSON-LD …@sl007 @hongminhee @julian i feel like you're falling into a trap i've seen a lot around AP spaces: just because the data can be contorted to represent something does not mean software will interpret it as such.
any software who wants to support wikidata statements and relations will have to go out of their way to implement that manually with or without json-ld in the mix, and interoperability between those software will have to specify how that works. and in your specification you can indeed make it so Simply Linking to the wikidata json-ld (which i don't believe it provides out of the box, it does for xml, turtle, and n-triples, if we're talking about rdf. if not, their bespoke json format is just as authoritative) can work (but i'd say using the Qxxx and Pxx IDs and letting the software figure out how to access it would be better!)
if you have the dream of making an as:Note and having it's as:attributedTo be the wikidata entity for alan turing... sorry, nobody other than maybe your own software will even attempt interpreting that -
@sl007 @hongminhee @julian i feel like you're falling into a trap i've seen a lot around AP spaces: just because the data can be contorted to represent something does not mean software will interpret it as such.
any software who wants to support wikidata statements and relations will have to go out of their way to implement that manually with or without json-ld in the mix, and interoperability between those software will have to specify how that works. and in your specification you can indeed make it so Simply Linking to the wikidata json-ld (which i don't believe it provides out of the box, it does for xml, turtle, and n-triples, if we're talking about rdf. if not, their bespoke json format is just as authoritative) can work (but i'd say using the Qxxx and Pxx IDs and letting the software figure out how to access it would be better!)
if you have the dream of making an as:Note and having it's as:attributedTo be the wikidata entity for alan turing... sorry, nobody other than maybe your own software will even attempt interpreting that@hongminhee @sl007 @julian attempting to support this kind of "data contortion" (i made this up and prolly isnt the right way to describe this) would rapidly balloon the scope of every fedi software ever. i don't believe anyone would want to develop for such ecosystem
a similar example i saw was someone attempting to explain how you can partially inline an as:object you as:Like'd in order to specify you only liked that past version of it and if it changed your like shouldn't count. without describing this exact scenario i don't believe any software, json-ld capable or not, would interpret that Like as such. same thing with the long-form text FEP which attempts to support non-activitypub authors -
@sl007 @hongminhee @julian i feel like you're falling into a trap i've seen a lot around AP spaces: just because the data can be contorted to represent something does not mean software will interpret it as such.
any software who wants to support wikidata statements and relations will have to go out of their way to implement that manually with or without json-ld in the mix, and interoperability between those software will have to specify how that works. and in your specification you can indeed make it so Simply Linking to the wikidata json-ld (which i don't believe it provides out of the box, it does for xml, turtle, and n-triples, if we're talking about rdf. if not, their bespoke json format is just as authoritative) can work (but i'd say using the Qxxx and Pxx IDs and letting the software figure out how to access it would be better!)
if you have the dream of making an as:Note and having it's as:attributedTo be the wikidata entity for alan turing... sorry, nobody other than maybe your own software will even attempt interpreting thatah, no - that is a misunderstanding!
Anyone can feel free to represent the texts only and the user at least "knows" it.
But the thing for Public Broadcasters means 47mio. users in DE alone and given the unified codebase for the 5 projects _these_ softwares will interpret it.
It does JSON-LD you could just check by asking for any JSON-LD e.g. Q1055 (Hamburg) - it is content-negotiation.
The taxiteam software is funded by the German yellow cabs - the official ones (!) the codename is FCKUBR
and I have no doubt about adoption fortunately.Maybe we can work out better examples …
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@hongminhee @sl007 @julian attempting to support this kind of "data contortion" (i made this up and prolly isnt the right way to describe this) would rapidly balloon the scope of every fedi software ever. i don't believe anyone would want to develop for such ecosystem
a similar example i saw was someone attempting to explain how you can partially inline an as:object you as:Like'd in order to specify you only liked that past version of it and if it changed your like shouldn't count. without describing this exact scenario i don't believe any software, json-ld capable or not, would interpret that Like as such. same thing with the long-form text FEP which attempts to support non-activitypub authorsit is just damned simple, your as: Client can do so much by asking wikidata, OSM, federated geocoding and not our system. When you use a property for the first time, the client can cache its names in the languages of the user etc.
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it is just damned simple, your as: Client can do so much by asking wikidata, OSM, federated geocoding and not our system. When you use a property for the first time, the client can cache its names in the languages of the user etc.
@sl007 @hongminhee @julian i genuinely can't see where json-ld is relevant here. if your client wants to support wikidata and OSM then it can do that with or without json-ld being involved. you are going to have to document how this integration works anyhow if you want anyone else to do so -
@hongminhee @sl007 @julian attempting to support this kind of "data contortion" (i made this up and prolly isnt the right way to describe this) would rapidly balloon the scope of every fedi software ever. i don't believe anyone would want to develop for such ecosystem
a similar example i saw was someone attempting to explain how you can partially inline an as:object you as:Like'd in order to specify you only liked that past version of it and if it changed your like shouldn't count. without describing this exact scenario i don't believe any software, json-ld capable or not, would interpret that Like as such. same thing with the long-form text FEP which attempts to support non-activitypub authorsjust btw, we had many W3C Social CG meetings about the importance and how to use the as:context property - not the JSON-LD @context and we all agreed.
About 30-40 devs attended.
Between 2016 and 2024 I attended basically any meeting. I felt that using wikidata urls in as:context was nice for anyone. -
@sl007 @hongminhee @julian i genuinely can't see where json-ld is relevant here. if your client wants to support wikidata and OSM then it can do that with or without json-ld being involved. you are going to have to document how this integration works anyhow if you want anyone else to do so
if I see wd: in lets say 3 of 12 AP software, I know tha I can give the user wikibase support.
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if I see wd: in lets say 3 of 12 AP software, I know tha I can give the user wikibase support.
anyway, if you like RDF and `content` is html how about RDFa ?
For us it would work similar. If we have any "convention" before we stop writing it might save time of rewriting -
just btw, we had many W3C Social CG meetings about the importance and how to use the as:context property - not the JSON-LD @context and we all agreed.
About 30-40 devs attended.
Between 2016 and 2024 I attended basically any meeting. I felt that using wikidata urls in as:context was nice for anyone.@sl007@digitalcourage.social eh? You use
context?ForumWG decided to use context to represent threads in threadiverse software (and Mastodon too, now).
Just FYI.
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