Attempt to handle routes with [AnyResponse] for Vapor3

Router+AnyReponseArray.swift

extension Router {
    @discardableResult
    func get(_ path: PathComponentsRepresentable..., use closure: @escaping (Request) throws -> [AnyResponse]) -> Route<Responder>
    {
        return _on(.GET, at: path.convertToPathComponents(), use: closure)
    }
    
    @discardableResult
    func post(_ path: PathComponentsRepresentable..., use closure: @escaping (Request) throws -> [AnyResponse]) -> Route<Responder>
    {
        return _on(.POST, at: path.convertToPathComponents(), use: closure)
    }
    
    @discardableResult
    func patch(_ path: PathComponentsRepresentable..., use closure: @escaping (Request) throws -> [AnyResponse]) -> Route<Responder>
    {
        return _on(.PATCH, at: path.convertToPathComponents(), use: closure)
    }
    
    @discardableResult
    func put(_ path: PathComponentsRepresentable..., use closure: @escaping (Request) throws -> [AnyResponse]) -> Route<Responder>
    {
        return _on(.PUT, at: path.convertToPathComponents(), use: closure)
    }
    
    @discardableResult
    func delete(_ path: PathComponentsRepresentable..., use closure: @escaping (Request) throws -> [AnyResponse]) -> Route<Responder>
    {
        return _on(.DELETE, at: path.convertToPathComponents(), use: closure)
    }
    
    @discardableResult
    private func _on(_ method: HTTPMethod, at path: [PathComponent], use closure: @escaping (Request) throws -> [AnyResponse]) -> Route<Responder>
    {
        let responder = BasicResponder { data in
            return try closure(data).map { try $0.encode(for: data) }.flatten(on: data).flatMap { responses in
                let contents = try responses.map { $0.http.body.data }
                                                        .compactMap { $0 }
                                                        .map { try JSONSerialization.jsonObject(with: $0, options: .allowFragments) }
                let jsonData = try JSONSerialization.data(withJSONObject: contents, options: JSONSerialization.WritingOptions(rawValue: 0))
                guard let string = String(data: jsonData, encoding: .utf8) else { throw Abort(.internalServerError, reason: "Unable to decode AnyResponse array") }
                return try string.encode(for: data) //it should return a json string with an array of response objects
            }
        }
        let route = Route<Responder>(path: [.constant(method.string)] + path, output: responder)
        register(route: route)
        return route
    }
}