How to test POST request?

Hi!

I wrote a test:

object AdminAuthHandlerTest : Spek({
    with(ktorTestEngine()) {
        describe("A sign-in endpoint") {
            lateinit var call: TestApplicationCall
            beforeGroup {
                call = handleRequest(HttpMethod.Post, "/api/admin/auth/sign-in") {
                    addHeader(HttpHeaders.Accept, ContentType.Text.Plain.contentType)
                    addHeader(HttpHeaders.ContentType, ContentType.Application.Json.contentType)
                    setBody(jsonAsString(AdminSignInRequest("admin", "admin123")))
                }
            }
            it("should return 200") {
                println("${call.request.bodyChannel.asString()} ${call.requestHandled}")
                assertThat(call.response.status()).isEqualTo(HttpStatusCode.OK)
            }
            it("should return token in response body") {
                assertThat(call.response.content).contains("token")
            }
            it("should return profile object in response body") {
                assertThat(call.response.content).contains("profile")
            }
            it("should set admin in call") {
                assertThat(call.admin).isNotNull()
            }
        }
    }
})

My test fails. In response, I always get 400 code, but I provide correct data in setBody method. When I do the request from Postman (or my client app) with the same data it works correctly.

fun jsonAsString(any: Any): String {
    return Gson().toJson(any)
}

I cannot find any information about a similar situation in docs. Do you have any idea what do I wrong?

[Stexxe]

@LookBad the root cause is BadContentTypeFormatException that is thrown, because of how you add Content-Type header in the app/test/src/handler/api/AdminAuthHandlerTest.kt:

addHeader(HttpHeaders.ContentType, ContentType.Application.Json.contentType)

contentType is a property of ContentType class that represents the first part of the media type — in your case application (from application/json). To fix this you can replace property access with toString() method call:

addHeader(HttpHeaders.ContentType, ContentType.Application.Json.toString())

[LookBad]

Wow! Thank you! I love it. It should be better documented.