LocalResponseCache support for Spring Cloud Gateway Server Web MVC

[ingogriebsch]

Is your feature request related to a problem? Please describe.
We would like to be able to cache responses and would therefore appreciate a filter in the Web MVC stack similar to the existing LocalResponseCache GatewayFilter in the Webflux stack.

Although we found the following page in the current documentation, we can't find a way to configure this filter or the code outlined in the documentation.

Describe the solution you'd like
The ability to configure a ResponseCache in the Web MVC stack in the same way as in the Webflux stack.

Describe alternatives you've considered
Implementing the filter ourselves. But this presents us with some challenges.

[nikita-kibitkin]

I can take this.

I would implement MVC route-level LocalResponseCache support using the same cacheability rules as the existing WebFlux filter: bodiless GET requests, 200/206/301 responses, Cache-Control/Vary handling, and per-route ttl/size options. I would avoid changing WebFlux behavior except for small shared cache-domain extraction if needed.

Should global MVC cache support be included here as well, or should this issue focus on the route-level filter?

[ingogriebsch]

@nikita-kibitkin I already started to prototype a solution. I did not share it yet on GitHub, though. But we can maybe share forces here! If you don't want to start straight away and could give me time until tomorrow, I can share what is already done.

I would also want to 'simply' take over what is implemented on the Webflux stack. And I also wanted to focus on route level and implement the global cache later on.