How to call a javascript function from Kotlin that expects a jQuery ajax settings object?

Question

I need to convert the following code, it uses something in jQuery called an ajax settings (which is used in the javascript below inside the create() call to create a CouchDB database)

$.couch.db("mydb").create({
    success: function(data) {
        console.log(data);
    },
    error: function(status) {
        console.log(status);
    }
});

I have defined these

@JsName("$")
external val jq: JQuery

val jCouch: dynamic get() = jq.asDynamic().couch

but I am stuck on how to convert the javascript code

jCouch.db.create("mydb").what now?

Answer 1

There are several ways. First, you can create a dynamic object and set required properties there:

val settings: dynamic = Any()
settings.success = { data: dynamic -> console.log(data) }
settings.error = { status: dynamic -> console.log(status) }
jCouch.db("db").create(settings)

(you may also specify corresponding type for data or status)

Second, you can use json function:

jCouch.db("db").create(json(
    "success" to { ... }, // edit note: added missing comma
    "error" to { ... }
))

Third, you can write typed headers. I don't know what is Couch API, so headers would look approximately like that:

external interface Db {
    fun create(settings: DbCreateSettings)
}

external interface DbResult

external interface DbError

external interface DbCreateSettings {
    val success: ((DbResult) -> Unit)?
    val error: ((DbError) -> Unit)?
}

fun JQuery.db(name: String): Db = asDynamic().db(name)

fun foo() {
    jq.db("name").create(object : DbCreateSettings {
        override val success = { it: DbResult -> console.log(it) }
        override val error = { it: DbError -> console.log(it) }
    })
}

Finally, you can see how Kotlin stdlib declares headers for options