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  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.

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  • evan@cosocial.caE evan@cosocial.ca

    @gugurumbe @cwebber @kopper @hongminhee AS2 requires compacted JSON-LD.

    evan@cosocial.caE This user is from outside of this forum
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    evan@cosocial.ca
    wrote last edited by
    #102

    There is no data format we can choose to eliminate programmer errors in online protocols. That's a quixotic aim.

    @gugurumbe @cwebber @kopper @hongminhee

    gugurumbe@mastouille.frG 1 Reply Last reply
    0
    • evan@cosocial.caE evan@cosocial.ca

      There is no data format we can choose to eliminate programmer errors in online protocols. That's a quixotic aim.

      @gugurumbe @cwebber @kopper @hongminhee

      gugurumbe@mastouille.frG This user is from outside of this forum
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      gugurumbe@mastouille.fr
      wrote last edited by
      #103

      @evan @kopper mentioned the async problem; if there’s no external contexts to fetch, then the recieving server can explicitly reject the request if it is incorrect.

      evan@cosocial.caE 1 Reply Last reply
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      • evan@cosocial.caE evan@cosocial.ca

        @cwebber @kopper @hongminhee It would be a huge backwards-incompatible change for almost zero benefit. People would still make mistakes in their ActivityPub implementations (sorry, Minhee, but that's life on an open network). We'd need to adopt another mechanism for defining extensions, and guess what? People are going to make mistakes with that, too.

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        ? Offline
        Guest
        wrote last edited by
        #104

        @evan @cwebber @kopper @hongminhee maybe a compromise approach could be to specify a simpler “json-ld as it is used in practice”, similar to what HTML5 was, that remains backward compatible while simplifying the spec to the point that it is actually feasible to implement

        1 Reply Last reply
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        • gugurumbe@mastouille.frG gugurumbe@mastouille.fr

          @evan @kopper mentioned the async problem; if there’s no external contexts to fetch, then the recieving server can explicitly reject the request if it is incorrect.

          evan@cosocial.caE This user is from outside of this forum
          evan@cosocial.caE This user is from outside of this forum
          evan@cosocial.ca
          wrote last edited by
          #105

          @gugurumbe @kopper I don't think that's the model of ActivityPub. It's made to allow reading remote objects.

          Most implementations pre-load or compile in the external contexts. I agree, it's a big performance hit to load context URLs at runtime.

          kopper@not-brain.d.on-t.workK 1 Reply Last reply
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          • evan@cosocial.caE evan@cosocial.ca

            @gugurumbe @kopper I don't think that's the model of ActivityPub. It's made to allow reading remote objects.

            Most implementations pre-load or compile in the external contexts. I agree, it's a big performance hit to load context URLs at runtime.

            kopper@not-brain.d.on-t.workK This user is from outside of this forum
            kopper@not-brain.d.on-t.workK This user is from outside of this forum
            kopper@not-brain.d.on-t.work
            wrote last edited by
            #106
            @evan @gugurumbe it's infeasible to preload all contexts, pretty much every pleroma instance hosts their own context on their own instance for example. then there is the obvious interop problems of how to handle contexts for new extensions your software is not aware of (though pretending like they're empty might work i guess?)
            gugurumbe@mastouille.frG evan@cosocial.caE trwnh@mastodon.socialT 3 Replies Last reply
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            • evan@cosocial.caE evan@cosocial.ca

              @cwebber @kopper @hongminhee

              I would be strongly opposed to any effort to remove JSON-LD from AS2. We use it for a lot of extensions. Every AP server uses the Security vocabulary for public keys.

              cwebber@social.coopC This user is from outside of this forum
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              cwebber@social.coop
              wrote last edited by
              #107

              @evan @kopper @hongminhee The problem is that signing json-ld is extremely hard, because effectively you have to turn to the RDF graph normalization algorithm, which has extremely expensive compute times. The lack of signatures means that when I boost peoples' posts, it takes down their instance, since effectively *every* distributed post on the network doesn't actually get accepted as-is, users dial-back to check its contents.

              Which, at that point, we might as well not distribute the contents at all when we post to inboxes! We could just publish with the object of the activity being the object's id uri

              kopper@not-brain.d.on-t.workK evan@cosocial.caE smallcircles@social.coopS rigo@mamot.frR 4 Replies Last reply
              0
              • cwebber@social.coopC cwebber@social.coop

                @evan @kopper @hongminhee The problem is that signing json-ld is extremely hard, because effectively you have to turn to the RDF graph normalization algorithm, which has extremely expensive compute times. The lack of signatures means that when I boost peoples' posts, it takes down their instance, since effectively *every* distributed post on the network doesn't actually get accepted as-is, users dial-back to check its contents.

                Which, at that point, we might as well not distribute the contents at all when we post to inboxes! We could just publish with the object of the activity being the object's id uri

                kopper@not-brain.d.on-t.workK This user is from outside of this forum
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                kopper@not-brain.d.on-t.work
                wrote last edited by
                #108
                @cwebber @hongminhee @evan admittedly, codeberg.org/fediverse/fep/src/branch/main/fep/8b32/fep-8b32.md does kind of solve this specific problem. the json canonicalization used there is much lighter than rdf canonicalization (which iceshrimp had to implement in dotNetRdf specifically for its ld signature support, so tooling availability is not really an excuse in favor of json-ld either!)
                cwebber@social.coopC 1 Reply Last reply
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                • kopper@not-brain.d.on-t.workK kopper@not-brain.d.on-t.work
                  @cwebber @hongminhee @evan admittedly, codeberg.org/fediverse/fep/src/branch/main/fep/8b32/fep-8b32.md does kind of solve this specific problem. the json canonicalization used there is much lighter than rdf canonicalization (which iceshrimp had to implement in dotNetRdf specifically for its ld signature support, so tooling availability is not really an excuse in favor of json-ld either!)
                  cwebber@social.coopC This user is from outside of this forum
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                  cwebber@social.coop
                  wrote last edited by
                  #109

                  @kopper @hongminhee @evan Interesting... I guess it means you can't re-compact with a new outer context, but maybe that's fine

                  1 Reply Last reply
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                  • cwebber@social.coopC cwebber@social.coop

                    @evan @kopper @hongminhee The problem is that signing json-ld is extremely hard, because effectively you have to turn to the RDF graph normalization algorithm, which has extremely expensive compute times. The lack of signatures means that when I boost peoples' posts, it takes down their instance, since effectively *every* distributed post on the network doesn't actually get accepted as-is, users dial-back to check its contents.

                    Which, at that point, we might as well not distribute the contents at all when we post to inboxes! We could just publish with the object of the activity being the object's id uri

                    evan@cosocial.caE This user is from outside of this forum
                    evan@cosocial.caE This user is from outside of this forum
                    evan@cosocial.ca
                    wrote last edited by
                    #110

                    @cwebber @kopper @hongminhee I talk about this in my book. Unless the receiving user is online at the time the server receives the Announce, it's ridiculous to fetch the content immediately. Receiving servers should pause a random number of minutes and then fetch the content. It avoids the thundering herd problem.

                    patmikemid@sfba.socialP julia@eepy.moeJ cwebber@social.coopC 3 Replies Last reply
                    0
                    • evan@cosocial.caE evan@cosocial.ca

                      @cwebber @kopper @hongminhee I talk about this in my book. Unless the receiving user is online at the time the server receives the Announce, it's ridiculous to fetch the content immediately. Receiving servers should pause a random number of minutes and then fetch the content. It avoids the thundering herd problem.

                      patmikemid@sfba.socialP This user is from outside of this forum
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                      patmikemid@sfba.social
                      wrote last edited by
                      #111

                      @evan @cwebber @kopper @hongminhee I think that is a better algorithm than a brain dead exponential back off. Perhaps put the two together.

                      evan@cosocial.caE 1 Reply Last reply
                      0
                      • kopper@not-brain.d.on-t.workK kopper@not-brain.d.on-t.work
                        @evan @gugurumbe it's infeasible to preload all contexts, pretty much every pleroma instance hosts their own context on their own instance for example. then there is the obvious interop problems of how to handle contexts for new extensions your software is not aware of (though pretending like they're empty might work i guess?)
                        gugurumbe@mastouille.frG This user is from outside of this forum
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                        gugurumbe@mastouille.fr
                        wrote last edited by
                        #112

                        @kopper It does not; if a malicious context redefines the security properties then the JSON-LD processor will understand the data differently than the unaware processor.

                        1 Reply Last reply
                        0
                        • patmikemid@sfba.socialP patmikemid@sfba.social

                          @evan @cwebber @kopper @hongminhee I think that is a better algorithm than a brain dead exponential back off. Perhaps put the two together.

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                          evan@cosocial.ca
                          wrote last edited by
                          #113

                          @patmikemid I call it trust, then verify. Usually caching the data with a ttl of a short number of minutes is enough.

                          @cwebber @kopper @hongminhee

                          cwebber@social.coopC 1 Reply Last reply
                          0
                          • kopper@not-brain.d.on-t.workK kopper@not-brain.d.on-t.work
                            @evan @gugurumbe it's infeasible to preload all contexts, pretty much every pleroma instance hosts their own context on their own instance for example. then there is the obvious interop problems of how to handle contexts for new extensions your software is not aware of (though pretending like they're empty might work i guess?)
                            evan@cosocial.caE This user is from outside of this forum
                            evan@cosocial.caE This user is from outside of this forum
                            evan@cosocial.ca
                            wrote last edited by
                            #114

                            @kopper @gugurumbe

                            https://en.wikipedia.org/wiki/Cache_%28computing%29

                            kopper@not-brain.d.on-t.workK natty@astolfo.socialN mia@void.rehabM 3 Replies Last reply
                            0
                            • evan@cosocial.caE evan@cosocial.ca

                              @kopper @gugurumbe

                              https://en.wikipedia.org/wiki/Cache_%28computing%29

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                              kopper@not-brain.d.on-t.work
                              wrote last edited by
                              #115
                              @evan @gugurumbe i know what caching is, thanks. in fact, my current project is building one that's tailor made for solving the activitypub thundering herd problem (codeberg.org/KittyShopper/middleap)

                              i've been trying to keep civil through this thread largely because i started the conversation mentioning software i (temporarily) help maintain and therefore represent it even implicitly, but leaving that aside and letting my own personal thoughts enter the picture:

                              i think this passive aggressive reply is the last straw. thinking that i somehow know enough to write code for this protocol without knowing what a cache is? plugging your book in a network largely developed by poor minorities (i myself have the rough equivalent of less than 40 USD in my bank account total)? this inability to consider change? ("as2 requires compaction",
                              because you're the one defining the spec saying it does), the inability to consider the people and software producing and building upon the data, as opposed to the data itself? the inability to consider the consequences of your specifications and how they're being used in the real world?

                              i honestly do not know if this line of thought is truly capable of leading this protocol out the slump it's currently in. if you're insistent on shooting yourself in the foot, so be it, but please take the time to consider how this behavior affects other people.

                              i've largely been burnt out of interacting in socialhub and other official protocol communities due to exactly this behavior, whether from you or others with influence on the final specs, and the only reason i keep trying is because of what's probably a self-destructive autistic hyperfixation on this niche network and trying to make it actually work for me and my friends, as opposed to
                              receiving funding from the well-known genocide enablers at meta and trying to shove failing standards where they don't belong.

                              please be a better example. if the protocol was actually desirable then sure, you may have earnt it, after all, atproto is teeming with silicon valley e/acc death cult weirdos and yet people seem to prefer it. have you wondered why?
                              or do you prefer to dismiss anything not coming from you without thinking about it
                              esm@wetdry.worldE evan@cosocial.caE 2 Replies Last reply
                              0
                              • evan@cosocial.caE evan@cosocial.ca

                                @cwebber @kopper @hongminhee I talk about this in my book. Unless the receiving user is online at the time the server receives the Announce, it's ridiculous to fetch the content immediately. Receiving servers should pause a random number of minutes and then fetch the content. It avoids the thundering herd problem.

                                julia@eepy.moeJ This user is from outside of this forum
                                julia@eepy.moeJ This user is from outside of this forum
                                julia@eepy.moe
                                wrote last edited by
                                #116

                                @evan@cosocial.ca @cwebber@social.coop @kopper@not-brain.d.on-t.work @hongminhee@hollo.social shared inboxes are a thing, Evan

                                The protocol isn't
                                just how it was initially defined. Protocols evolve and change from their ideals to fit the needs of their operation, and getting rid of individual inboxes is one of those changes.

                                Social media platforms are real-time- you can't just defer stuff like that.

                                evan@cosocial.caE 1 Reply Last reply
                                0
                                • julia@eepy.moeJ julia@eepy.moe

                                  @evan@cosocial.ca @cwebber@social.coop @kopper@not-brain.d.on-t.work @hongminhee@hollo.social shared inboxes are a thing, Evan

                                  The protocol isn't
                                  just how it was initially defined. Protocols evolve and change from their ideals to fit the needs of their operation, and getting rid of individual inboxes is one of those changes.

                                  Social media platforms are real-time- you can't just defer stuff like that.

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                                  evan@cosocial.ca
                                  wrote last edited by
                                  #117

                                  @julia @cwebber @hongminhee @kopper

                                  Hi! 👋🏼 Nice to meet you. I'm well aware of `sharedInbox` and helped design it.

                                  Realtime is an illusion. You can make it pretty convincing.

                                  Your users are mostly not online. Remote users are mostly not online. Tracking the last time remote and local users were seen can help you prioritize local and remote delivery.

                                  It's a lot better to deliver to the tiny percent of users currently online first rather than delivering to the user named `aaaaaaaaamng` first.

                                  julia@eepy.moeJ panos@ibe.socialP 2 Replies Last reply
                                  0
                                  • evan@cosocial.caE evan@cosocial.ca

                                    @julia @cwebber @hongminhee @kopper

                                    Hi! 👋🏼 Nice to meet you. I'm well aware of `sharedInbox` and helped design it.

                                    Realtime is an illusion. You can make it pretty convincing.

                                    Your users are mostly not online. Remote users are mostly not online. Tracking the last time remote and local users were seen can help you prioritize local and remote delivery.

                                    It's a lot better to deliver to the tiny percent of users currently online first rather than delivering to the user named `aaaaaaaaamng` first.

                                    julia@eepy.moeJ This user is from outside of this forum
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                                    julia@eepy.moe
                                    wrote last edited by
                                    #118

                                    @evan@cosocial.ca @cwebber@social.coop @hongminhee@hollo.social @kopper@not-brain.d.on-t.work I feel like deferring activity resolution and publishing based on online status would only serve to create more reasons for your average person to feel that the fediverse is unstable- explaining the logistics of the herd problem to someone who doesn't know what a distributed system is is kinda difficult.

                                    evan@cosocial.caE 1 Reply Last reply
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                                    • evan@cosocial.caE evan@cosocial.ca

                                      @kopper @gugurumbe

                                      https://en.wikipedia.org/wiki/Cache_%28computing%29

                                      natty@astolfo.socialN This user is from outside of this forum
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                                      natty@astolfo.social
                                      wrote last edited by
                                      #119

                                      @evan@cosocial.ca @kopper@not-brain.d.on-t.work @gugurumbe@mastouille.fr Evan, to put it bluntly, the status quo only creates a further divide between the "big certified implementations" and the small implementation independent developers can make without worrying about making the implementation vulnerable-by-default

                                      There could totally be a body that at least
                                      attempts to standardize well-known LD prefixes while retaining compatibility with JSON-LD (like IANA and protocol schemes), but there isn't

                                      There could be a
                                      subset of JSON-LD that prohibits common pitfalls, but there is not one. In fact, there are very few high-quality openly available libraries that can process ActivityPub objects. There is no way to declare the actual shapes of objects without heavy fuzzing.

                                      There is no safe amount of JSON-LD in a distributed network where context URIs may fade in and out of existence. I'm saying distributed because that's essentially what happens in practice over sufficient time.

                                      Can we for the love of all that's serializable shrink the state space of this mess? It's possible and it's actionable, without anyone left out. We don't need a Rube-Goldberg machine to share a JPEG online

                                      1 Reply Last reply
                                      0
                                      • kopper@not-brain.d.on-t.workK kopper@not-brain.d.on-t.work
                                        @evan @gugurumbe i know what caching is, thanks. in fact, my current project is building one that's tailor made for solving the activitypub thundering herd problem (codeberg.org/KittyShopper/middleap)

                                        i've been trying to keep civil through this thread largely because i started the conversation mentioning software i (temporarily) help maintain and therefore represent it even implicitly, but leaving that aside and letting my own personal thoughts enter the picture:

                                        i think this passive aggressive reply is the last straw. thinking that i somehow know enough to write code for this protocol without knowing what a cache is? plugging your book in a network largely developed by poor minorities (i myself have the rough equivalent of less than 40 USD in my bank account total)? this inability to consider change? ("as2 requires compaction",
                                        because you're the one defining the spec saying it does), the inability to consider the people and software producing and building upon the data, as opposed to the data itself? the inability to consider the consequences of your specifications and how they're being used in the real world?

                                        i honestly do not know if this line of thought is truly capable of leading this protocol out the slump it's currently in. if you're insistent on shooting yourself in the foot, so be it, but please take the time to consider how this behavior affects other people.

                                        i've largely been burnt out of interacting in socialhub and other official protocol communities due to exactly this behavior, whether from you or others with influence on the final specs, and the only reason i keep trying is because of what's probably a self-destructive autistic hyperfixation on this niche network and trying to make it actually work for me and my friends, as opposed to
                                        receiving funding from the well-known genocide enablers at meta and trying to shove failing standards where they don't belong.

                                        please be a better example. if the protocol was actually desirable then sure, you may have earnt it, after all, atproto is teeming with silicon valley e/acc death cult weirdos and yet people seem to prefer it. have you wondered why?
                                        or do you prefer to dismiss anything not coming from you without thinking about it
                                        esm@wetdry.worldE This user is from outside of this forum
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                                        esm@wetdry.world
                                        wrote last edited by
                                        #120

                                        @kopper @evan @gugurumbe thank you for saying this; the relatively poor DX is one thing, but i could get around that if it weren't for the insistence by the authors and major developers here on minimizing much of the very real problems of this protocol/network and then complaining about those who look elsewhere without considering why they would want to do that

                                        i continue to maintain existing stuff for this network, but i'm incredibly hesitant to make anything new mostly due to the reasons stated above - especially when we have other options now

                                        1 Reply Last reply
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                                        • evan@cosocial.caE evan@cosocial.ca

                                          @kopper @gugurumbe

                                          https://en.wikipedia.org/wiki/Cache_%28computing%29

                                          mia@void.rehabM This user is from outside of this forum
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                                          mia@void.rehab
                                          wrote last edited by
                                          #121

                                          @evan @kopper @gugurumbe what, you got a book on caching you want to plug too?

                                          1 Reply Last reply
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