Vaadin 12 pass object to JavaScript's function: Can't encode class

Question

Vaadin 12, Kotlin project

In my myPage.html I has javascript:

 myObject.redirectToCheckout({
                    sessionId: "1111_2222",
                }).

So I need to call javaScript function redirectToCheckout from Vaadin 12 and pass correct param as object. So here my Vaadin snippet:

import com.vaadin.flow.component.dependency.HtmlImport
import com.vaadin.flow.component.dependency.JavaScript
import com.vaadin.flow.component.html.Div
import com.vaadin.flow.router.Route
import com.vaadin.flow.server.VaadinRequest
import java.io.Serializable

@Route(value = "redir")
@HtmlImport("styles/myPage.html")
class RedirectForm : Div() {
    init {
        val request = VaadinRequest.getCurrent()
        val paramGoto = request.getParameter("goto")
        val redirect = Redirect("$paramGoto")
        UI.getCurrent().getPage().executeJavaScript("myObject.redirectToCheckout($0)", redirect) // **error here**
    }

    inner class Redirect : Serializable {
        var sessionId: String

        constructor(sessionId: String) {
            this.sessionId = sessionId
        }
    }
}

but I get error:

Caused by: java.lang.IllegalArgumentException: Can't encode class com.myproject.view.RedirectForm$Redirect to json
    at com.vaadin.flow.internal.JsonCodec.encodeWithoutTypeInfo(JsonCodec.java:165)
    at com.vaadin.flow.internal.JsonCodec.encodeWithTypeInfo(JsonCodec.java:80)
    at com.vaadin.flow.component.page.Page.executeJavaScript(Page.java:338)
    at com.myproject.view.RedirectForm.<init>(RedirectView.kt:28)
    ... 50 common frames omitted

Answer 1

Use JsonObject instead Redirect:

val request = VaadinRequest.getCurrent()
val paramGoto = request.getParameter("goto")
val json = Json.createObject()
json.put("sessionId", "$paramGoto")
UI.getCurrent().getPage().executeJavaScript("myObject.redirectToCheckout($0)", json)