(-ish of course, you'll probably also need to construct
MySeqs etc. but the basic principle stands)
There used to be a library that specifically claimed to be the fastest dom rendering lib in sjs, but I cannot remember the name and I also cannot find it.
Does anyone remember a library like that?
works great rendering vdom nodes or strings too
Hi all, Scala.js noob here (and webdev noob as well - I do know Scala though). I would be glad for guidance on the following. I have an AWS Cognito login which returns a JWT token. Based on what I've read about JWT tokens, here is how I think it should work: 1) user completes Cognito login, receives a token. 2) Scala.JS saves the token and adds it to every request header going forward. 3) server validates the token at every request. Does that sound reasonable? Or am I heading in the wrong direction? And which ScalaJS methods can I use on the client side? Cheers
Yes it sounds reasonable. The JWT must be sent in a header for all requests to the server. For how to do it, it mostly depends what library you are using to make your http calls from your frontend. This could be: plain old XMLHttpRequest, the less old JS fetch function (in both these cases, refer to the excellent MDN docs), sttp library (in that case, refer to their docs) or perhaps something else (the last one I know of is roshttp
any advice on how to store the token on the client side?
Of course you could also decide that your backend puts it in a cookie, then you have nothing to do
Is there no
Evidence[String, js.Any] or any of the other values that are implicitly js.Any (by casting)?
Seems to work fine:
val a: AnyRef | Unit = "Hello"
println(a)
val b: AnyRef | Unit = ()
println(b)
val c: String | Unit = "Hello"
val d: AnyRef | Unit = c
println(d)
ScalablyTyped will convert
value?: any; to value: UndefOf[js.Any]. Should I raise a bug with ST then?
I think I see what you mean by it not working in Scala 3:
import scala.language.implicitConversions
trait JsAny extends scala.AnyRef
object JsAny {
given Conversion[String, JsAny] = _.asInstanceOf[JsAny]
}
val a: String | Unit = "Hello"
val b: JsAny | Unit = "Goodbye"
//Found: (Playground.a : String | Unit)
//Required: Playground.JsAny | Unit
//val c: JsAny | Unit = a
val d: JsAny | Unit = a match
case s: String => s
case () => ()In practice you can use a String value in place of a js.Any and a js.Any | Unit because it will be converted implicitly but a String is not a subtype of js.Any and so String | Unit is not a jsAny | Unit either. That's a bit awkward.
:point_up: Edit: I think I see what you mean by it not working in Scala 3:
import scala.language.implicitConversions
trait JsAny extends scala.AnyRef
object JsAny {
given Conversion[String, JsAny] = _.asInstanceOf[JsAny]
}
val a: String | Unit = "Hello"
val b: JsAny | Unit = "Goodbye"
//Found: (Playground.a : String | Unit)
//Required: Playground.JsAny | Unit
//val c: JsAny | Unit = a
val d: JsAny | Unit = a match
case s: String => s
case () => ()In practice you can use a String value in place of a js.Any and a js.Any | Unit because it will be converted implicitly but a String is not a subtype of js.Any and so String | Unit is not a jsAny | Unit either. That's a bit awkward.
And no, there is no way.
You're not supposed to inspect or rely on names anyway.
Even fastOpt can change the names as it pleases (and we actually do sometimes).
I am just getting going with scala.js and noticed that if I add
scalacOptions := Seq(
...
)to build.sbt then run fails and does not produce "Hello World"
I am using 3.1.0-RC2 but the same happend with 3.0.1
sometimes I have to add an option such as
"-Yexplicit-nulls"
This i with the minimal setup given in the first page of the documentation https://www.scala-js.org/doc/tutorial/basic/
I got some help in Discord. I needed to use
++= rather than :=scalacOptions ++= Seq(...)
also
dom.window.indexedDB suddenly returns js.UndefOr[IDBFactory] instead of IDBFactory
If I do this
req.onerror = {
case e: dom.ErrorEvent => // XXX TODO: why this guarantee broke in scalajs DOM 1.2.0 ?
pr.failure(failure(e))
case _ =>
pr.failure(new IOException(req.error.message))
}I just get isInstanceOf[org.scalajs.dom.raw.ErrorEvent] not supported because it is a JS trait. So I have to furthe rewrite an existing library? :(
do I just cast
asInstanceOf[ErrorEvent], or ... ?
If guarantees are broken, it's normally because the DOM doesn't actually give that guarantee.
You can cast if you don't want to change your code.
It looks like the js api passes an
Event and not an ErrorEvent so this might just be a correction: https://developer.mozilla.org/en-US/docs/Web/API/IDBRequest/onerror
I ran into a similar issue with Xhr
If you really have to match on it, use
(x: Any) match { case ... }
In that case you have to use ad hoc logic to identify in which case you are, then cast.