Hi. I'm using Spring Webflux and have controllers ...

# spring

[Daniel Imber]

Hi. I'm using Spring Webflux and have controllers with suspending functions. I'd like to have all of those controller functions invoked with a coroutine that has an element within the coroutine context. The best I can think of so far is to manually add the context element as withContext inside each and every controller function - something like this:

@GetMapping("/foo")
    suspend fun getFoo(): Foo {
        withContext(SomeCoroutineContextElement()) {
            TODO("Do something")
        }
    }

Is there a better way - i.e. a way to add the context across all controller functions, so I don't need to litter every one of them with withContext?

[todd.ginsberg]

I'd be interested in this as well. We use the MDC to pass along a correlation id in most of our apps, and doing it with suspend functions would require the same thing you are talking about here. Very interested in a way around that.

[Ben]

I'm not sure with annotated controllers but with the functional style you can do it in a filter.

filter { request, next -> withContext() { next(request) } }

[Daniel Imber]

🤔 I wonder if we can mix functional filter and annotated controller as the handler. Shouldn't be hard to test...

[Ben]

I wasn't able to find a way to do it.

[Daniel Imber]

Yep I wasn’t able to either. Thanks for the tip around the functional filters though. 👍