Repository Case 1

RepositoryCase1.swift

// The Model
final class User: Model  {
    typealias Database = MySQLDatabase /// the problem is this line
    typealias ID = Int

    static var idKey: IDKey { return \.id }

    var id: Int?
    var name: String
    var email: String
}

// The Repository
protocol UserRepository: ServiceType {
    func all() -> Future<[User]>
}

final class MySQLUserRepository: UserRepository {
    let db: MySQLDatabase.ConnectionPool

    init(_ db: MySQLDatabase.ConnectionPool) {
        self.db = db
    }

    func all() -> Future<[User]> {
        return db.withConnection { conn in
            return User.query(on: conn).all()
        }
    }
}
// The Controller
struct UsersController {

    func getAllHandler(_ req: Request) throws -> Future<[User]> {
        let repository = try req.make(UsersRepository.self)
         return repository.all()
    }
}