connect does not notify the user when a websocket connection isn't upgraded

[EthanLozano]

Describe the bug

(Apologies in advance: I'm not sure which layer is potentially failing, or if I'm failing to interact with a layer properly. There is a good chance that this isn't a bug with websocket-kit)

WebSocket.connect does not appear to notify the user if the server decides not to upgrade the request. Specifically, .whenFailure is never triggered on the resulting EventLoopFuture.

To Reproduce

I'm using a vapor server, and my webSocket route defines a shouldUpgrade function that returns nil (under certain conditions):

shouldUpgrade: { req in
    ...
    req.eventLoop.makeSucceededFuture(nil)
}

I believe that returning nil is the correct use of the vapor API, but I also tried returning a failed future without any success:

req.eventLoop.makeFailedFuture(Abort(.forbidden))

On the client side, no code is triggered to alert the client that the upgrade failed

let result = WebSocket.connect(...)
result.whenFailure { error in
    // not triggered
}

Expected behavior

I would expect .whenFailure to be executed. Or, I would expect the API to support a closure for when the upgrade was rejected.

Environment

• Vapor websocket-kit: 2.1.2
• Vapor Framework version: 4.35.0
• Vapor Toolbox version: 18.0.0
• OS version: Mac OS 11.0.1 (20B50)

[fumoboy007]

The root cause for this issue is vapor/vapor#2932.