WebClient.ResponseSpec.onStatus, Unexpected behavior when response body empty

[danielra]

When I use the WebClient.ResponseSpec.onStatus method and try to create an exception that requires the response body content but the response body is empty, the Flux returned by a subsequent bodyToFlux call actually receives an onComplete instead of the expected onError.

To illustrate the behavior, I've created a sample project which reproduces the unexpected behavior in a test case here: https://github.com/danielra/webclient_response_spec_onstatus_empty_response_body_issue_repro
The project uses spring boot version 2.1.1.RELEASE as seen here.

When run via ./gradlew test --debug the test case (here) which has at least one character of response body content passes as expected - but the test case which has an empty response body (here) unexpectedly fails.

Please let me know if any further information would be useful.

[poutsma]

With the introduction of ClientResponse::createException in 5.2, it is no longer necessary to consume the body bytes themselves. Using that method, I was not able to reproduce this issue.

Closing this issue for now, but let us know if there is something to look at.

[rstoyanchev]

Most likely superseded by #22825.