Fix exception handling when a message consumer is blocking

[cescoffier]

When a message consumer fails and uses blocking=true, the caught exception must be captured and sent to the sender as reply exception.

[cescoffier]

CC @tsegismont

[cescoffier]

@gsmet Marked this PR as backporting (after approval and merge of course), as it's clearly a bug. The fix should not conflict with anything else (famous last words)

[mkouba]

@cescoffier Could you pls elaborate a bit about why is this fix needed?

[mkouba]

BTW we should probably update our generated code to use io.vertx.core.Promise instead of io.vertx.core.Future...

[cescoffier]

When failing the future, as done before, the sender do not get the exception (the vertx global exception handler does). With this it gets a failed reply and can react.

[tsegismont]

@mkouba the related issue is #12599

[tsegismont]

LGTM, thanks @cescoffier

I trust that the body of verifyFailure is the same as in MessageConsumerFailureBlockingTest. Perhaps to better show that there shouldn't be any difference between blocking/non-blocking the two tests could be merged? That's up to you I'm fine with the PR.

[cescoffier]

Yeah, I should be able to reuse the same method, let me fix this.

[cescoffier]

@tsegismont Fixed, I merged both tests.

[gsmet]

I cancelled CI as I need the slots for an emergency release, will restart them later.

[mkouba]

Ah, now I finally understand! Thanks for the fix.