4 ms·

WebSub is the successor to PubSubHubBub, which was designed to make distribution of RSS items more efficient (ie receive items as they are published on the hos

by rakoo 8y ago

WebSub is the successor to PubSubHubBub, which was designed to make distribution of RSS items more efficient (ie receive items as they are published on the host): - publisher would send updates, instead of having everyone poll - publisher would be protected from thundering herd if a content suddenly becomes popular - publisher and subscribers wouldn't need to exchange a full "page" of items when only one is needed

antpls 8y ago
> distribution of RSS items more efficient RSS is a 500kb static text file which is updated usually at most every hours. The whole file fits in server RAM and can already be served to thousands of people from cache with minimal CPU usage, or from Content Delivery Networks. A "full page of items" is easily compressed with gzip algorithms. Surely, the Internet isn't congested because of RSS...
- fenwick67 8y ago
  Don't forget about ETags.
MuffinFlavored 8y ago
> - publisher would send updates, instead of having everyone poll Publisher still has to send the update to the thundering herd, no?
- rakoo 8y ago
  No, see the diagram (https://www.w3.org/TR/websub/websub-overview.svg https://www.w3.org/TR/websub/websub-overview.svg): publisher tells the hub "here's the new content", the hub is in charge of contacting each and every subscriber telling them "here's the new content". Only the hub _could_ be overwhelmed, but it works at its own rhythm so it has more control. The thundering herd happens when you have an incontrollable influx of traffic coming in, and you have no way to regulate it.
  - antpls 8y ago
    This is ridiculous. Any big enough palteforms such as Medium or Reuters will already partner with CDN, cloud firewalls, automatic provisioning, etc to handle traffic. For small self-hosted blogs, authors can pay a CDN that will absorb any exceptional loads and almost cost nothing the rest of the time. Eventually the blog will go down for 24h and will be back online when things get calmer. The idea of creating a hub that will be a central point is the opposite of distributed information.
    - deleted 8y ago
      [deleted]
    - VoxPelli 8y ago
      Funny that Medium then decided to buy a company that was built around WebSub and was founded by one of the authors of the spec: https://techcrunch.com/2016/06/02/super-to-medium/ https://techcrunch.com/2016/06/02/super-to-medium/ Seems like they do find some use for it? (As does eg Google who has it as the preferred real-time deliver mechanism for sitemaps.)
      - antpls 8y ago
        > (As does eg Google who has it as the preferred real-time deliver mechanism for sitemaps.) Again, totally random fact without any single source to prove it. WebSub basically comes from the need of that one entreprise? Does it worth making it a W3C specification?
saurik 8y ago
This sounds great in principle, but this is 2018... virtually none of the use cases for RSS can be replaced by something which requires the consumer to be online and capable of receiving an HTTP POST (which isn't possible on the web platform at all, so this shouldn't be called WebSub). To the extent to which a "thundering herd" ever existed for RSS, it was from large numbers end users with normal computers behind firewalls constantly checking the feed, which is an environment where this protocol has no hope of ever being applicable. So far, no one on this entire thread has descried a single use case where WebSub actually provides value. Someone mentioned that theoretically a service like Facebook could use this for Facebook, but then they themselves linked to a page on Quora with an explanation from someone at Facebook for why they tested out PubSubHubbub and then gave up on it which stated that he "think[s] the benefits of adopting PubSubHubbub are less clear" for this very issue (that it is inherently a server-to-server protocol, where there wasn't really a problem in the first place).
- rakoo 8y ago
  Are you saying that webhooks have no purpose in 2018 ? Because while WebSub was created as an effort to help RSS get more realtime, it's a more generic architecture for publishers who have content and need to notify interested subscribers.
  - antpls 8y ago
    What we are saying is : In the attempt at understanding the use cases of this proposal, people said in the thread webhooks were created to replace RSS+GET pull, as an "enhancement". As we are trying to explain : this proposal doesn't cover all use cases of RSS+GET pull, so it should not be considered a replacement of RSS nor an enhancement of it. If WebSub has a purpose (if any), many people fail to explain a valid one. Does it worth wasting the resources of the W3C for such proposal? The "world wide web" is wide, and doesn't only include servers
    - rakoo 8y ago
      > people said in the thread webhooks were created to replace RSS+GET pull That's the root of our misunderstanding then: never was PubSubHubbub _replacing_ RSS+GET pull, it was supposed to _help_ it for people who want notifications, on top of the existing system.

by rakoo 8y ago

antpls 8y ago

> distribution of RSS items more efficient RSS is a 500kb static text file which is updated usually at most every hours. The whole file fits in server RAM and can already be served to thousands of people from cache with minimal CPU usage, or from Content Delivery Networks. A "full page of items" is easily compressed with gzip algorithms. Surely, the Internet isn't congested because of RSS...

fenwick67 8y ago
Don't forget about ETags.

MuffinFlavored 8y ago

> - publisher would send updates, instead of having everyone poll Publisher still has to send the update to the thundering herd, no?

rakoo 8y ago
No, see the diagram (https://www.w3.org/TR/websub/websub-overview.svg https://www.w3.org/TR/websub/websub-overview.svg): publisher tells the hub "here's the new content", the hub is in charge of contacting each and every subscriber telling them "here's the new content". Only the hub _could_ be overwhelmed, but it works at its own rhythm so it has more control. The thundering herd happens when you have an incontrollable influx of traffic coming in, and you have no way to regulate it.
- antpls 8y ago
  This is ridiculous. Any big enough palteforms such as Medium or Reuters will already partner with CDN, cloud firewalls, automatic provisioning, etc to handle traffic. For small self-hosted blogs, authors can pay a CDN that will absorb any exceptional loads and almost cost nothing the rest of the time. Eventually the blog will go down for 24h and will be back online when things get calmer. The idea of creating a hub that will be a central point is the opposite of distributed information.
  - deleted 8y ago
    [deleted]
  - VoxPelli 8y ago
    Funny that Medium then decided to buy a company that was built around WebSub and was founded by one of the authors of the spec: https://techcrunch.com/2016/06/02/super-to-medium/ https://techcrunch.com/2016/06/02/super-to-medium/ Seems like they do find some use for it? (As does eg Google who has it as the preferred real-time deliver mechanism for sitemaps.)
    - antpls 8y ago
      > (As does eg Google who has it as the preferred real-time deliver mechanism for sitemaps.) Again, totally random fact without any single source to prove it. WebSub basically comes from the need of that one entreprise? Does it worth making it a W3C specification?

saurik 8y ago

This sounds great in principle, but this is 2018... virtually none of the use cases for RSS can be replaced by something which requires the consumer to be online and capable of receiving an HTTP POST (which isn't possible on the web platform at all, so this shouldn't be called WebSub). To the extent to which a "thundering herd" ever existed for RSS, it was from large numbers end users with normal computers behind firewalls constantly checking the feed, which is an environment where this protocol has no hope of ever being applicable. So far, no one on this entire thread has descried a single use case where WebSub actually provides value. Someone mentioned that theoretically a service like Facebook could use this for Facebook, but then they themselves linked to a page on Quora with an explanation from someone at Facebook for why they tested out PubSubHubbub and then gave up on it which stated that he "think[s] the benefits of adopting PubSubHubbub are less clear" for this very issue (that it is inherently a server-to-server protocol, where there wasn't really a problem in the first place).

rakoo 8y ago
Are you saying that webhooks have no purpose in 2018 ? Because while WebSub was created as an effort to help RSS get more realtime, it's a more generic architecture for publishers who have content and need to notify interested subscribers.
- antpls 8y ago
  What we are saying is : In the attempt at understanding the use cases of this proposal, people said in the thread webhooks were created to replace RSS+GET pull, as an "enhancement". As we are trying to explain : this proposal doesn't cover all use cases of RSS+GET pull, so it should not be considered a replacement of RSS nor an enhancement of it. If WebSub has a purpose (if any), many people fail to explain a valid one. Does it worth wasting the resources of the W3C for such proposal? The "world wide web" is wide, and doesn't only include servers
  - rakoo 8y ago
    > people said in the thread webhooks were created to replace RSS+GET pull That's the root of our misunderstanding then: never was PubSubHubbub _replacing_ RSS+GET pull, it was supposed to _help_ it for people who want notifications, on top of the existing system.