Vapor 4 Authentication Issue [User is not authenticated] - swift

Question

I have an iOS client with OAuth 2.0 as an authenticating mechanism.
When a user signs in, I authenticate him with this method (Google sign in for example):
func processGoogleLogin(request: Request, token: String) throws -> EventLoopFuture<ResponseEncodable> {
try Google
.getUser(on: request)
.flatMap { userInfo in
User
.query(on: request.db)
.filter(\.$email == userInfo.email)
.first()
.flatMap { foundUser in
guard let existingUser = foundUser else {
//creating a new user
return user
.save(on: request.db)
.map {
request.session.authenticate(user)
//redirecting with info
}
}
request.session.authenticate(existingUser)
//redirecting with info
}
}
}
After the login, I want to check if the user is authenticated and if I've successfully authenticated the user.
So I have an endpoint that I protect from unauthenticated users, but even after signing in, the user cannot access this endpoint as he is not authenticated.
Error:
{
"error": true,
"reason": "User not authenticated."
}
My User Model conforms to ModelSessionAuthenticatable.
I also use the SessionMiddleware (ImpreialController is the auth controller):
let imperialController = ImperialController(sessionsMiddleware: app.sessions.middleware)
app.middleware.use(app.sessions.middleware)
In ImperialController:
class ImperialController {
private let sessionsMiddleware: Middleware
init(sessionsMiddleware: Middleware) {
self.sessionsMiddleware = sessionsMiddleware
}
....
And finally the protected route:
let protected = app.grouped(User.guardMiddleware())
protected.get { req -> HTTPResponseStatus in
return .ok
}

Answer 1

It may be that you are doing it, but just not showing it in your question. You need to create and register an instance of SessionsMiddleware using something like this:
app.middleware.use(SessionsMiddleware(session: MemorySessions(storage: MemorySessions.Storage())))
Do this before you create the instance of your controller.
EDIT in reply to OP' comment:
I normally pass the instances of the different middleware explicitly because I tend to apply subsets to groups of routes rather than all the middleware. For example:
app.middleware.use(FileMiddleware(publicDirectory: app.directory.publicDirectory))
app.middleware.use(SessionsMiddleware(session: MemorySessions(storage: MemorySessions.Storage())))
app.middleware.use(User.sessionAuthenticator(.mysql))
try app.register(collection: APIController(middleware: UserToken.authenticator()))
var middleware: [Middleware] = [CustomMiddleware.InternalErrorMiddleware()]
try app.register(collection: InsecureController(middleware: middleware))
middleware.append(contentsOf: [User.redirectMiddleware(path: [C.URI.Solidus].string),
User.authenticator(), User.guardMiddleware(),
CustomMiddleware.SessionTimeoutMiddleware()])
try app.register(collection: CustomerController(middleware: middleware))
BTW, have you included my line 3 above? That may be your problem.