Add ability to append ServerHttpRequest for kotlin-spring generator

[Rugal]

Hi

I am creating kotlin-spring based spring-webflux application. I would like to access request header, but there is no way to achieve without adding function parameter. After checking all the available configuration and option, I found no feasible way to append an additional ServerHttpRequest to request handler, hence to add made this simple change in order to resolve the requirement.

I Would like to discuss with people who interested in having request parameter in method.
Since the one I append here is for spring webflux and reactive, therefore I put ServerHttpRequest which is a reactive only interface. Should I take spring mvc into consideration so that in that case the request object type should be HttpServletRequest?

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[wing328]

thanks for the PR. please follow step 3 to update the samples and the doc.

[Rugal]

thanks for the PR. please follow step 3 to update the samples and the doc.

step 3 is completed and doc is updated

[wing328]

Hi @Rugal thanks again for the PR.

can you please add a config to enable/test this new option similar to ./bin/configs/kotlin-spring-boot-delegate.yaml ?

commit the new samples and then update .github/workflows/samples-kotlin-server.yaml with the new sample folder so that CI can test this feature moving forward?

[wing328]

I added the new sample files via 45f8acc

Let's see if all the tests pass

[wing328]

the CI tests for the new sample failed: https://github.com/OpenAPITools/openapi-generator/actions/runs/7162598645/job/19499791008?pr=17158

can you please take a look when you've time?

[Rugal]

Will do once get some spare time, thanks for letting me know.
I realize that the generated code does not contain expected ServerHttpRequest parameter. Need to look into reason before pushing the test sample.

[wing328]

take your time. let me know if you need any help.

thanks again for the PR.

[Rugal]

Updated. Now the generated sample contains expected ServerHttpRequest parameter.

[Rugal]

For context and possible discussion detail @wing328 , please refer to the PR brief where I updated with some of my thoughts.

[wing328]

https://github.com/OpenAPITools/openapi-generator/actions/runs/7181198352/job/20313881200?pr=17158

please update the samples and then i'll merge. thanks again for the PR.

[wing328]

merged. will update the samples with another commit.

[wing328]

Hi @Rugal the CI tests failed: https://github.com/OpenAPITools/openapi-generator/actions/runs/7526797968/job/20485651712

can you please take a look when you've time?

[Rugal]

Hi @Rugal the CI tests failed: https://github.com/OpenAPITools/openapi-generator/actions/runs/7526797968/job/20485651712

can you please take a look when you've time?

Sure, will do it ASAP

[Rugal]

Hi @wing328,

A fix is ready here

[defaultbranch]

@Rugal Thanks for your efforts!

Just today (using openapi-generator-maven-plugin:7.2.0), I discovered that there is a kotlin-spring generator, and after using the spring generator for >1 year, I thought I'd give kotlin-spring a try (my motivation is explained further below).

I have a comment:

• instead of ServerHttpRequest, I was so far using ServerWebExchange provided by the spring generator

and two questions:

1. why do you go for ServerHttpRequest instead of ServerWebExchange? Wouldn't the later be closer to what the spring generator already provides?
2. (assuming that both ServerHttpRequest and ServerWebExchange serve a similar purpose, so the difference does not matter much), what is the status of your <appendRequestToHandler>, what are the remaining obstacles to get this functionality into the kotlin-spring generator?

---

My motivation is, I want to use the option <reactive>true</reactive>, but so far (with the spring generator) this meant Project Reactor which is great but only works at the library/framework level (it has to cope with the limitations of the Java language); Kotlin supports similar functionality at compiler level (thanks to its co-routines), which simplifies the code a great deal; and I was already happy to see that the generator option <reactive>true</reactive> is actually the same for the spring (Java with Project Reactor) and kotlin-spring (Kotlin co-routines). Today I tried the kotlin-spring generator (instead of spring generator) (via openapi-generator-maven-plugin:7.2.0) for the first time, and I figured out that the option <appendRequestToHandler>true</appendRequestToHandler> does nothing much yet, so far it only adds an import statement to the generated code.

[Rugal]

Hi @defaultbranch ,

My initial motivation for this change is that I would like to access request header information in handler/operation. Because I was using webflux, which is a reactive framework, while still want to be able to access request object.
After some search, I found ServerHttpRequest is quite a good fit for my need.
The appendRequestToHandler parameter should be able to generate an import, but also to append the ServerHttpRequest to method signature as well.
Your suggestion is great, I think we can replace the request with exchange, which contains both request and response.