I’m trying to migrate to ktor 2.0 and I’m facing an issue with tests. Currently I’m using `withTestA...

# ktor

[KamilH]

I’m trying to migrate to ktor 2.0 and I’m facing an issue with tests. Currently I’m using withTestApplication where I call Application.module function with some arguments like that:

withTestApplication({
    module(appModule = appModule)
}) { ... }

now we are suppose to use testApplication function that seemingly calls Application.module function automatically, so passing custom arguments seems not possible anymore and it makes testing much more difficult. Is there any way to call Application.module manually? Is there any workaround?

[phldavies]

You should be able to something like

testApplication {
  application {
    module(appModule = appModule)
  }
  // ... test using `client` or `createClient { ... }`
}

[hruan]

testApplication picks up application.conf and will automatically load modules there (e.g. Application.module. If you want a different set of modules all together, you can modify `environment`: https://ktor.io/docs/testing.html#add-modules

[KamilH]

Thanks Phil, but when I do that my Application.module gets called twice, so my plugins gets installed twice and it results in exception

[KamilH]

@hruan it seems like it’s the information I was missing. Thanks!

[phldavies]

try

testApplication {
            environment {
                modules.clear()
                modules.add(appModule)
            }
}

[ribesg]

testApplication should have a useApplicationConf: Boolean = true parameter or something like that to let you disable this behavior. Maybe I want an application.conf file in my main source set and maybe I don’t want to use it in my tests

[phldavies]

you can override the config to load (either by file or from map, etc) in the environment block: https://ktor.io/docs/testing.html#environment

[ribesg]

Isn’t that after the fact? In your code just above you removed modules from an existing collection, means they’re already loaded from the config file, doesn’t it?

[phldavies]

It may well be the code I provided doesn’t work - I’ve not used the HOCON/config based Ktor approach - I tend to use an embeddedServer. Hence “try” 😉 but you’re right - it might be better to remove/change/override the config.

[ribesg]

Well I just thought everything inside the testApplication block happened after the config had been read but maybe it’s not the case

[phldavies]

My understanding is, the testApplication block doesn’t action the configuration until the first client request is made (and the test engine is started)

[KamilH]

Using approach with custom .conf file in test/resource folder, mentioned here worked well. I’ve left modules empty and no modules are loaded:

// test/resource/application-test.conf
ktor {
    application {
        modules = [ ]
    }
}


@Test
fun test() = testApplication {
    environment {
        config = ApplicationConfig("application-test.conf")
    }
}