Jetty 12 with Jakarta EE 8 (Servlet 4) and 9 (Servlet 5) causes `java.lang.IllegalArgumentException: demand pending`

[kevin-lee]

Jetty 12 with Jakarta EE 8 (Servlet 4) and 9 (Servlet 5) causes java.lang.IllegalArgumentException: demand pending

The issue was reported on the Jetty side:
Seeing java.lang.IllegalArgumentException: demand pending during load testing (#11694)

[kevin-lee]

@rossabaker Hi, Roos. I'm back again. Would you mind creating the series/0.22 branch at https://github.com/http4s/http4s-servlet?

I'm working on http4s-jetty to support Servlet 5 (Jakarta EE 9) and 6 (Jakarta EE 10), so I need the http4s-servlet branch for http4s 0.22. I've already created branches for http4s-servlet 0.22 and http4s-servlet 0.24 (or what would be the right version for http4s 0.23?), and they're almost done.

The reason I'm working on this urgently is because of the following issue:
Seeing java.lang.IllegalArgumentException: demand pending during load testing (#11694)

It looks like the fix was applied only to JEE 10 (Servlet 6):
Fix IllegalArgumentException: demand pending (#11721)

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(Sorry, I already said it in this comment on http4s-jetty.)

[rossabaker]

I created series/0.22 as a base. Do you need any fixes in this project, or do you just need something published against the jakarta namespace that's compatible with http4s-0.22? It seems like maybe you could just update that dependency to servlet-5, give the artifact a new name similar to what we did with Jetty, and be done? Jetty 12 should be able to consume that same artifact for both EE9 and EE10.

As for http4s-0.23, the servlet-0.24 branch is Servlet 4, the http4s-servlet-0.25 branch is Servlet 5, and the http4s-servlet-0.26 branch (still unpublished) is Servlet 6. I think you could move forward with http4s-servlet-0.25. http4s-servlet-0.26 hasn't been a priority because we're not using any Servlet 6 specific features, but we could go ahead and get a tag on it while we're here.

[kevin-lee]

@rossabaker Thanks. I'll check those and update my branches accordingly to ensure mine matches with those.

[rossabaker]

I think #399 is basically what has to be done for 0.22 if you really need servlet4, servlet5, and servlet6. I'm hoping we don't need to do anything like that for http4s-0.23... I think you can just use 0.24, 0.25, and 0.26 as they are for those? They're tested on old versions of Jetty, but I don't think that matters.

I've been thinking about converting the tests to Glassfish, but it's very scarcely used compared to Jetty or Tomcat, and the module boundaries weren't easy to follow.

[kevin-lee]

I think #399 is basically what has to be done for 0.22 if you really need servlet4, servlet5, and servlet6. I'm hoping we don't need to do anything like that for http4s-0.23... I think you can just use 0.24, 0.25, and 0.26 as they are for those? They're tested on old versions of Jetty, but I don't think that matters.

@rossabaker Sure, As you mentioned before ("As for http4s-0.23, the servlet-0.24 branch is Servlet 4, the http4s-servlet-0.25 branch is Servlet 5, and the http4s-servlet-0.26 branch (still unpublished) is Servlet 6."), I'll make sure to use the separate branches for http4s 0.23.

I've been thinking about converting the tests to Glassfish, but it's very scarcely used compared to Jetty or Tomcat, and the module boundaries weren't easy to follow.

@rossabaker OK, yeah, I agree.