When using the <Locations> plugin, is there a way ...

# ktor

[Stylianos Gakis]

When using the Locations plugin, is there a way to specify the body variables instead of just the query parameters?

For example I want to have something like this

@Location("/login")
data class PostLogin(val username: String, val password: String)

But I want the username and the password to be part of the body of the post request instead of the Params.

Is that something that is possible, or must I do call.receive like I would when I wasn’t using the Locations plugin?

[nschulzke]

No, there is not, which is one major weak point in the locations plugin.

You can write your own without too much difficulty. I just did it myself to solve a few issues I had with the official plugin, and while I can't release the code yet, I can give you some pointers if you're interested.

[Stylianos Gakis]

It was mostly for a pet-project I am playing around with simply to learn a bit more about ktor/server side dev. I highly doubt I’m the person to do a deep dive on the matter unfortunately.
For now I just removed the Locations and I am trying out using the <http://Route.post|Route.post> method that allows you to pass a reified type and it does the call.receive() for you allowing me to write a route that looks something like this:

@Serializable
data class Login(val username: String, val password: String)

post<Login>("login") { login: Login ->
    val response = authController.login(
        Username(login.username), Password(login.password)
    )
    call.respondWith(response)
}

I guess that’s too bad that I can’t use the Locations plugin, but if it can’t do that for me, I don’t see a reason for me to use it other than a prettier way to define the routes.

[nschulzke]

You can generate URLs from the Locations, which would mean, if you were generating all your URLs server-side, you could rename endpoints by just changing the annotation in one place. However, in most cases, your URLs aren't all going to be generated server-side (they're located in an SPA or a mobile app), so the value there is minimal.

A typed multiplatform locations API would be really powerful, as it would allow you to guarantee the correct URLs and request/response bodies are used across all platforms, but it doesn't seem to be a priority for the Ktor team. If I can get the one I built stabilized, I'll see if I can get approval to release it as open-source.

[Stylianos Gakis]

Yeah it sounds like a worthy thing to build. I hope it goes well for you and that you will be able to open-source it!

[Dominaezzz]

There's a POC PR on ktor btw