Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • World
  • Users
  • Groups
Skins
  • Light
  • Cerulean
  • Cosmo
  • Flatly
  • Journal
  • Litera
  • Lumen
  • Lux
  • Materia
  • Minty
  • Morph
  • Pulse
  • Sandstone
  • Simplex
  • Sketchy
  • Spacelab
  • United
  • Yeti
  • Zephyr
  • Dark
  • Cyborg
  • Darkly
  • Quartz
  • Slate
  • Solar
  • Superhero
  • Vapor

  • Default (No Skin)
  • No Skin
Collapse
We Distribute
  1. Home
  2. Technical Discussion
  3. 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.

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.

Scheduled Pinned Locked Moved Technical Discussion
fedifyjsonldfedidevactivitypub
168 Posts 35 Posters 286 Views
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • potatomeow@fosstodon.orgP This user is from outside of this forum
    potatomeow@fosstodon.orgP This user is from outside of this forum
    potatomeow@fosstodon.org
    wrote last edited by
    #66

    @hongminhee i struggling badly with rust cuz it's rust being rust... i can imagine a duck typing lang might have easier time

    potatomeow@fosstodon.orgP 1 Reply Last reply
    0
    • potatomeow@fosstodon.orgP potatomeow@fosstodon.org

      @hongminhee i struggling badly with rust cuz it's rust being rust... i can imagine a duck typing lang might have easier time

      potatomeow@fosstodon.orgP This user is from outside of this forum
      potatomeow@fosstodon.orgP This user is from outside of this forum
      potatomeow@fosstodon.org
      wrote last edited by
      #67

      @hongminhee most of the time, i cant compile if really do jsonld as it is. unless i box everything onto the heap. but then it became a de-optimization point to the rest of the software

      1 Reply Last reply
      0
      • sl007@digitalcourage.socialS sl007@digitalcourage.social

        @julian

        Can you specify "threadiverse" software cause like all properties which are not marked as "functional" in the ActivityPub Spec, `context` is an Array and I do not see any problem …

        sl007@digitalcourage.socialS This user is from outside of this forum
        sl007@digitalcourage.socialS This user is from outside of this forum
        sl007@digitalcourage.social
        wrote last edited by
        #68

        @julian

        ^ what I mean :

        "context": [
        "https://threadiversesoftware.example.org/thread/123",
        "https://www.wikidata.org/wiki/Special:EntityData/Q64 "
        ];

        just says:
        "Hi machine, I am in the context of thread 123 about Berlin."

        1 Reply Last reply
        0
        • sl007@digitalcourage.socialS This user is from outside of this forum
          sl007@digitalcourage.socialS This user is from outside of this forum
          sl007@digitalcourage.social
          wrote last edited by
          #69

          @julian

          Is ther a W3C minutes or kind of a meeting-protocol|spec. about this use of context?

          julian@activitypub.spaceJ 1 Reply Last reply
          0
          • sl007@digitalcourage.socialS sl007@digitalcourage.social

            @julian

            Is ther a W3C minutes or kind of a meeting-protocol|spec. about this use of context?

            julian@activitypub.spaceJ This user is from outside of this forum
            julian@activitypub.spaceJ This user is from outside of this forum
            julian@activitypub.space
            wrote last edited by
            #70

            @sl007@digitalcourage.social FEPs 7888 and f228 details the use of context and one use case of it, to backfill conversations.

            sl007@digitalcourage.socialS 1 Reply Last reply
            0
            • julian@activitypub.spaceJ julian@activitypub.space

              @silverpill@mitra.social POSTing that inbox sends a 404?

              silverpill@mitra.socialS This user is from outside of this forum
              silverpill@mitra.socialS This user is from outside of this forum
              silverpill@mitra.social
              wrote last edited by
              #71

              @julian Yes, POST to personal inbox sends a 404, POST to group inbox sends a 202 (I guess group inbox is how we communicate now).

              1 Reply Last reply
              1
              • julian@activitypub.spaceJ julian@activitypub.space

                @sl007@digitalcourage.social FEPs 7888 and f228 details the use of context and one use case of it, to backfill conversations.

                sl007@digitalcourage.socialS This user is from outside of this forum
                sl007@digitalcourage.socialS This user is from outside of this forum
                sl007@digitalcourage.social
                wrote last edited by
                #72

                @julian

                well, but that is _exactly_ the same of the official Social CG meetings !

                "This context property is the URL of the NodeBB topic."
                vs.
                "The context property should be used to identify the context in which the object appears in, form a common topic or group content. This can be a well known JSON-LD vocabulary or any ActivityPub Object useful for the implementation."
                vs
                https://www.w3.org/TR/activitystreams-vocabulary/#dfn-context :

                „Identifies the context within which the object exists or an activity was performed.
                The notion of "context" used is intentionally vague. The intended function is to serve as a means of grouping objects and activities that share a common originating context or purpose. An example could be all activities relating to a common project or event. “

                and I am glad cause, as said
                "context": [
                "https://threadiversesoftware.example.org/thread/123",
                "https://www.wikidata.org/wiki/Special:EntityData/Q64 "
                ];
                then says:
                "Hi machine, I am in the context of thread 123 about Berlin."

                and then

                🧵 1/2

                sl007@digitalcourage.socialS 1 Reply Last reply
                0
                • sl007@digitalcourage.socialS sl007@digitalcourage.social

                  @julian

                  well, but that is _exactly_ the same of the official Social CG meetings !

                  "This context property is the URL of the NodeBB topic."
                  vs.
                  "The context property should be used to identify the context in which the object appears in, form a common topic or group content. This can be a well known JSON-LD vocabulary or any ActivityPub Object useful for the implementation."
                  vs
                  https://www.w3.org/TR/activitystreams-vocabulary/#dfn-context :

                  „Identifies the context within which the object exists or an activity was performed.
                  The notion of "context" used is intentionally vague. The intended function is to serve as a means of grouping objects and activities that share a common originating context or purpose. An example could be all activities relating to a common project or event. “

                  and I am glad cause, as said
                  "context": [
                  "https://threadiversesoftware.example.org/thread/123",
                  "https://www.wikidata.org/wiki/Special:EntityData/Q64 "
                  ];
                  then says:
                  "Hi machine, I am in the context of thread 123 about Berlin."

                  and then

                  🧵 1/2

                  sl007@digitalcourage.socialS This user is from outside of this forum
                  sl007@digitalcourage.socialS This user is from outside of this forum
                  sl007@digitalcourage.social
                  wrote last edited by
                  #73

                  @julian

                  and then
                  1) machine gets thread (cause is JSON-LD by known/allowed `generator`)
                  2) machine fetches or gets cached wikidata entry about Berlin and displays the card (kind of "infobox" then).
                  .. from the named "SpecialEntitiyData" of wikidata which is JSON-LD as well.
                  3) machine is happy

                  apart from our tools, I need to credit Max Lath who is doing inventaire, the federated book library and did a lot of previous work for wiki JSON-LD like the wonderful https://github.com/maxlath/wikibase-sdk

                  sl007@digitalcourage.socialS 1 Reply Last reply
                  0
                  • sl007@digitalcourage.socialS sl007@digitalcourage.social

                    @julian

                    and then
                    1) machine gets thread (cause is JSON-LD by known/allowed `generator`)
                    2) machine fetches or gets cached wikidata entry about Berlin and displays the card (kind of "infobox" then).
                    .. from the named "SpecialEntitiyData" of wikidata which is JSON-LD as well.
                    3) machine is happy

                    apart from our tools, I need to credit Max Lath who is doing inventaire, the federated book library and did a lot of previous work for wiki JSON-LD like the wonderful https://github.com/maxlath/wikibase-sdk

                    sl007@digitalcourage.socialS This user is from outside of this forum
                    sl007@digitalcourage.socialS This user is from outside of this forum
                    sl007@digitalcourage.social
                    wrote last edited by
                    #74

                    @julian

                    PS - just btw;
                    about inventaire I am sharing currently photobooks for free rent in Dortmund, Germany
                    https://inventaire.io/users/sl007
                    they have also nice use for JSON-LD re. books /authors etc. https://data.inventaire.io/ like so many software in fedi.
                    If you ask the redaktor Service Actor for Place (`Question`) to find you a waffle restaurant in Amsterdam serving blue syrup near a train station then we do also use SPARQL like them - without the AI bullshit - just cause millions of friendly humans contributing to wd and OSM …

                    1 Reply Last reply
                    0
                    • mcc@mastodon.socialM This user is from outside of this forum
                      mcc@mastodon.socialM This user is from outside of this forum
                      mcc@mastodon.social
                      wrote last edited by
                      #75

                      @hongminhee How hard would it be for a future version of ActivityPub to simply back out JSON-LD support? Would there be a downside to this?

                      julian@activitypub.spaceJ hongminhee@hollo.socialH cochise@social.subversida.deC 3 Replies Last reply
                      1
                      • mcc@mastodon.socialM mcc@mastodon.social

                        @hongminhee How hard would it be for a future version of ActivityPub to simply back out JSON-LD support? Would there be a downside to this?

                        julian@activitypub.spaceJ This user is from outside of this forum
                        julian@activitypub.spaceJ This user is from outside of this forum
                        julian@activitypub.space
                        wrote last edited by
                        #76

                        @mcc@mastodon.social asking the important questions 🤣

                        @hongminhee@hollo.social

                        1 Reply Last reply
                        0
                        • mcc@mastodon.socialM mcc@mastodon.social

                          @hongminhee How hard would it be for a future version of ActivityPub to simply back out JSON-LD support? Would there be a downside to this?

                          hongminhee@hollo.socialH This user is from outside of this forum
                          hongminhee@hollo.socialH This user is from outside of this forum
                          hongminhee@hollo.social
                          wrote last edited by
                          #77

                          @mcc@mastodon.social I'm not sure, but that would break some ActivityPub implementations relying on JSON-LD processors. 🤔

                          1 Reply Last reply
                          0
                          • mcc@mastodon.socialM mcc@mastodon.social

                            @hongminhee How hard would it be for a future version of ActivityPub to simply back out JSON-LD support? Would there be a downside to this?

                            cochise@social.subversida.deC This user is from outside of this forum
                            cochise@social.subversida.deC This user is from outside of this forum
                            cochise@social.subversida.de
                            wrote last edited by
                            #78

                            @mcc @hongminhee Mastodon, Fedify and other implementations that treat LD as mandatory (MUST) even if it's optional (SHOULD) will be non conformant. As Mastodon is the biggest implementation by far margin, deprecating it is no small feat.

                            mcc@mastodon.socialM 1 Reply Last reply
                            0
                            • cochise@social.subversida.deC cochise@social.subversida.de

                              @mcc @hongminhee Mastodon, Fedify and other implementations that treat LD as mandatory (MUST) even if it's optional (SHOULD) will be non conformant. As Mastodon is the biggest implementation by far margin, deprecating it is no small feat.

                              mcc@mastodon.socialM This user is from outside of this forum
                              mcc@mastodon.socialM This user is from outside of this forum
                              mcc@mastodon.social
                              wrote last edited by
                              #79

                              @cochise @hongminhee But Mastodon famously doesn't actually *support* LD right? That's the point of the thread? So wouldn't they be the easiest to convince to stop supporting the thing they never supported?

                              cochise@social.subversida.deC 1 Reply Last reply
                              0
                              • mcc@mastodon.socialM mcc@mastodon.social

                                @cochise @hongminhee But Mastodon famously doesn't actually *support* LD right? That's the point of the thread? So wouldn't they be the easiest to convince to stop supporting the thing they never supported?

                                cochise@social.subversida.deC This user is from outside of this forum
                                cochise@social.subversida.deC This user is from outside of this forum
                                cochise@social.subversida.de
                                wrote last edited by
                                #80

                                @mcc @hongminhee Don't really support, but discards activities without @context anyway.

                                I suspect JSON-LD was a way to have extensibility and escape XMPP's XEP hell with servers and clients not supporting or disabling features in an infinite matrix.
                                But seems community favors FEPs describing JSON schemas and hardcoding it over getting them from a server and mapping the object at runtime.

                                trwnh@mastodon.socialT 1 Reply Last reply
                                0
                                • kanru@g0v.socialK This user is from outside of this forum
                                  kanru@g0v.socialK This user is from outside of this forum
                                  kanru@g0v.social
                                  wrote last edited by
                                  #81

                                  @hongminhee I had a similar realization early on when implementing Pinka. I almost went full JSON-LD but found that to properly expand the document I might need to make network calls. I stopped worrying about unknown terms and just hard coded a list of well-known AS and APub terms for interoperability.

                                  trwnh@mastodon.socialT 1 Reply Last reply
                                  0
                                  • trwnh@mastodon.socialT This user is from outside of this forum
                                    trwnh@mastodon.socialT This user is from outside of this forum
                                    trwnh@mastodon.social
                                    wrote last edited by
                                    #82

                                    @hongminhee what i have found necessary (sadly) is to sometimes ignore what @\context a software produces and simply inject a corrected @\context describing what they *actually* meant instead of what they said they meant. x_x

                                    Link Preview Image
                                    the "incorrect" mastodon context in use right now (or equivalent), which can be swapped out for the "correct" mastodon context to be more compatible with generic json-ld (and more semantically correct)

                                    the "incorrect" mastodon context in use right now (or equivalent), which can be swapped out for the "correct" mastodon context to be more compatible with generic json-ld (and more semantically correct) - mastodon-context-correct.jsonld

                                    favicon

                                    Gist (gist.github.com)

                                    it would be an Exercise to sit down and map out the actual contexts of softwares like mastodon 4.5, mastodon 4.4, misskey 2025.12, akkoma 3.10.2, and so on...

                                    for all else, there's shacl i guess, if you want to beat things into the correct shapes.

                                    julian@activitypub.spaceJ 1 Reply Last reply
                                    0
                                    • kanru@g0v.socialK kanru@g0v.social

                                      @hongminhee I had a similar realization early on when implementing Pinka. I almost went full JSON-LD but found that to properly expand the document I might need to make network calls. I stopped worrying about unknown terms and just hard coded a list of well-known AS and APub terms for interoperability.

                                      trwnh@mastodon.socialT This user is from outside of this forum
                                      trwnh@mastodon.socialT This user is from outside of this forum
                                      trwnh@mastodon.social
                                      wrote last edited by
                                      #83

                                      @kanru @hongminhee ironically this is what you're supposed to do! preload the terms you understand into local contexts. newer jsonld-adjacent specs (vc, cid, and so on) tell you that you MUST NOT fetch the contexts over the network at runtime, and instead MUST treat them as already fetched with a given sha256sum. https://www.w3.org/TR/cid-1.0/#json-ld-context

                                      1 Reply Last reply
                                      0
                                      • trwnh@mastodon.socialT This user is from outside of this forum
                                        trwnh@mastodon.socialT This user is from outside of this forum
                                        trwnh@mastodon.social
                                        wrote last edited by
                                        #84

                                        @julian @mcc @hongminhee the downside is that you now need a central registry of allowed terms and what they mean.

                                        the way to avoid that is to always use "expanded" form, i.e. use full IRIs as property keys (and types) and {"id": "foo"} over "foo". in effect, you treat the http(s) authority as the social entity defining the term.

                                        1 Reply Last reply
                                        0
                                        • cochise@social.subversida.deC cochise@social.subversida.de

                                          @mcc @hongminhee Don't really support, but discards activities without @context anyway.

                                          I suspect JSON-LD was a way to have extensibility and escape XMPP's XEP hell with servers and clients not supporting or disabling features in an infinite matrix.
                                          But seems community favors FEPs describing JSON schemas and hardcoding it over getting them from a server and mapping the object at runtime.

                                          trwnh@mastodon.socialT This user is from outside of this forum
                                          trwnh@mastodon.socialT This user is from outside of this forum
                                          trwnh@mastodon.social
                                          wrote last edited by
                                          #85

                                          @cochise @mcc @hongminhee mastodon is one of the "better" ones in that regard, but famously requires you to have the same context as it (instead of expanding shorthand terms to the full IRIs and comparing those...)

                                          1 Reply Last reply
                                          0
                                          Reply
                                          • Reply as topic
                                          Log in to reply
                                          • Oldest to Newest
                                          • Newest to Oldest
                                          • Most Votes


                                          • Login

                                          • Don't have an account? Register

                                          • Login or register to search.
                                          Powered by NodeBB Contributors
                                          • First post
                                            Last post
                                          0
                                          • Categories
                                          • Recent
                                          • Tags
                                          • Popular
                                          • World
                                          • Users
                                          • Groups