Hi all Ist there a way to easily unit-testing a kt...

# ktor

[Roger Kreienbühl]

Hi all
Ist there a way to easily unit-testing a ktor client plugin, without mocking the whole ktor client?
I have a simple plugin that uses only onResponse

[Bruce Hamilton]

Generally we use testApplication and install on the client there and test with the server.

Here's an example from CallIdTest in the Ktor repository:

@Test
fun testCallIdChainingFromCoroutineContext() = testApplication {
    val client = createClient {
        install(CallId)
    }

    install(ServerCallId) {
        generate { "call-id-1" }
    }
    routing {
        get("/1") {
            call.respond(client.get("2").bodyAsText())
        }
        get("2") {
            respondWithCallId()
        }
    }

    val response = client.get("/1").bodyAsText()
    assertEquals(response, "call-id-1:call-id-1:call-id-1")
}

[Aleksei Tirman [JB]]

With testApplication, the client and the server are connected, so they don't use a real network. Unfortunately, it's not possible to test a plugin in isolation.

[Roger Kreienbühl]

Ok, thanks for your responses, will use testApplication then.

[Arjan van Wieringen]

I would just extract the logic that is passed to onResponse and test only that logic… if possible

[Aleksei Tirman [JB]]

That would require mocking the ApplicationCall which depends on other interfaces.

[Roger Kreienbühl]

I had time to look into this and ended up using io.ktor:ktor-client-mock to test the client plugin