Review Http[Input|Output].Interceptor

[sbordet]

Jetty version
10.0.x

Description
Http[Input|Output].Interceptor are underspecified and need to be reviewed and clarified.

This issue stems from work on #6163 and also #6156 and #6010.

Interceptors are not allowed to throw checked exceptions, so they have to wrap failures in runtime exceptions, which would be unnecessary.

Furthermore, if an interceptor throws, the exception handling needs to be careful in both blocking and non-blocking I/O.

@lachlan-roberts @lorban @gregw please add your comments about this matter.

[sbordet]

@lorban please use this issue as an umbrella to port #6163 to Jetty 10.

However, this issue is also for HttpOutput.Interceptor so you may want to issue a PR for HttpInput but not close this issue until also HttpOutput is done.

[lachlan-roberts]

The HttpOutput.Interceptor can fail the callback instead of throwing, however failing the callback causes the connection to be aborted with no 500 response even if the HttpChannel is not committed.

[gregw]

An interesting question is that if there is a failure during an async write (either in interceptor or below) then should it be thrown from the call to async write? If we don't throw, then the caller might loop on isReady and write, never seeing the exception. We can't call onError because we are already in onWritePossible. @sbordet how sure are we that we have not introduced such a loop with the new catches?

So i think we should throw.... but then do we call onError as well once the call to onWritePossible returns?

[lorban]

HttpInput side is done.

[github-actions]

This issue has been automatically marked as stale because it has been a
full year without activity. It will be closed if no further activity occurs.
Thank you for your contributions.

[github-actions]

This issue has been automatically marked as stale because it has been a
full year without activity. It will be closed if no further activity occurs.
Thank you for your contributions.

[github-actions]

This issue has been automatically marked as stale because it has been a
full year without activity. It will be closed if no further activity occurs.
Thank you for your contributions.

[sbordet]

Closing, as Jetty 12 does not have interceptors anymore.