Reject "/path/**/other" patterns in PathPatternParser

Issue:

Created 2 mappings as following in the controller, code is in Controller .javaof the attached project.

@GetMapping("/foo/**")
public ResponseEntity getFoo() {}

@GetMapping("/foo/**/bar")
public ResponseEntity getFooBar() {}

• In webmvc whenever request comes as /foo/1/2/3/bar (as far as last path segment is bar) it maps to getFooBar.
• If bar is not specified ast last path segment then it maps to getFoo. i.e all foo/1, foo/1/2, foo/ab/cd… maps to getFoo.
• The issue is in webflux, when I switch to webflux all mappings map to getFoo. No matter if path consists of bar in the last path segment.
• For eg. /foo/ab/cd/bar maps to getFoo instead of getFooBar.

Uploaded the project here , to switch between webflux and webmvc please comment out appropriate starter dependency in pom.xml.

Repro project here : https://github.com/kaladhar-mummadi/demo-issue

Notes:

• Webmvc AntPathMatcherTests has tests like /bla/**/bla, which are not covered in PathPatternTests of WebFlux.

[bclozel]

I see a recent ticket #24945 to align MVC towards using PathPatternParser. Won’t this be a breaking change ?

This won’t be a breaking change since we’ll support both AntPathMatcher and PathPatternParser infrastructures for Spring MVC, leaving the current one as the default. This just gives an extra choice for developers interested in optimal path matching performance (we’re getting quite a few requests about that).

I wonder why there are different strategies used for WebFlux and MVC. Would have been better if the change remained consistent across both.

WebFlux was a completely new effort and we took that opportunity to revisit parts we wanted to improve. Aligning both MVC and WebFlux right away in Spring Framework 5.0 wouldn’t have been a wise choice since at that point we didn’t have much experience/feedback on running WebFlux applications in production.

As for adding that feature to PathPatternParser, I don’t think we should do that for the reasons listed above. Even if WebFlux applications are less popular than MVC apps, I believe it’s the first time we’re getting an issue about this since 5.0 is out (in 2017).

[ranarula]

@bclozel - I see a recent ticket https://github.com/spring-projects/spring-framework/issues/24945 to align MVC towards using PathPatternParser. Won’t this be a breaking change ?

I wonder why there are different strategies used for WebFlux and MVC. Would have been better if the change remained consistent across both.