Since apparently routes have their own pipeline (<...

# ktor

[Felix]

Since apparently routes have their own pipeline (https://ktor.io/advanced/pipeline/route.html), is it possible to install a feature on a route's pipeline?
I tried doing something like

route("/foo", HttpMethod.Get) {
            install(ExampleFeature)
            handle {...}
}

However the feature appears to run for all routes.

[bdawg.io]

What does the feature do? You can Route.intercept stages specific to a route, but Application.install will always be scoped to the entire application

[orangy]

If ExampleFeature is defined for an Application, you can’t install it into a Route. Unfortunately, we didn’t find a way to issue an error or a warning, when this happens. DslMarker is not powerful enough in this case.

[orangy]

If you want it to work with Routes, a feature should be implemented for ApplicationCallPipeline

[Felix]

Thanks for the reply. My feature was in indeed implementing ApplicationFeature<Application, ...> and not ApplicationFeature<ApplicationCallPipeline, ...>. By switching to the last one I get the expected behaviour: the feature interceptor only runs if the request goes to the route where it was installed.

[Felix]

When I had my feature implementing ApplicationFeature<Application, ...>, there was no error during install and the interceptor ran for all requests, which was surprising.

[orangy]

That’s because it got attached to the receiver of the outer lambda (or function). There is DslMarker mechanics in the language, but unfortunately it is not enough in this case