This demo app is an iOS allows a user login and retrieves all his investor products using Moneybox API. User session is saved securely inside the Apple Keychain while the products are fetched at each session.
This project is oriented toward the following patterns:
✅ VIPER Architecture
✅ Protocol Oriented
✅ Functional Programming
✅ Clean Code
✅ Dependency Injection
✅ Unit Tests
The project contains 3 main sections:
- Utils: utilities and extensions
- Core: networking module
- Sections: VIPER module
🔸 Facade
The core layer is managed by a facade
struct MCURLServiceFacade {
private let configuration: MCURLConfiguration
init(configuration: MCURLConfiguration) {
self.configuration = configuration
}
var baseUrl: URL? {
URL(string: configuration.baseUrl)
}
var authToken: String {
configuration.keychain.userSession()?.session.bearerToken ?? ""
}
func makeRequest<T: Decodable>(_ request: MCURLRequest,
map: T.Type,
completion: @escaping ((Result<T, Error>) -> Void)) throws {
let urlRequest = request
.appendingHeaders(configuration.decorators)
.build()
configuration
.service
.performTask(with: urlRequest) { responseData, urlResponse, responseError in
completion(self.makeDecode(response: responseData,
urlResponse: urlResponse,
map: map,
error: responseError))
}
}
private func makeDecode<T: Decodable>(response: Data?,
urlResponse: URLResponse?,
map: T.Type,
error: Error?) -> (Result<T, Error>) {
if let error = error { return (.failure(error)) }
guard let jsonData = response else { return (.failure(MCServiceError.noData)) }
let statusCode = urlResponse?.httpResponse?.statusCode ?? MCConstants.URL.statusCodeOk
guard statusCode >= MCConstants.URL.statusCodeOk &&
statusCode < MCConstants.URL.statusCodemultipleChoice else {
return decode(response: jsonData,
map: ErrorModel.self)
.mapError(code: statusCode)
}
return decode(response: jsonData,
map: map)
}
private func decode<T: Decodable>(response: Data,
map: T.Type) -> (Result<T, Error>) {
do {
let decoded = try JSONDecoder().decode(map,
from: response)
return (.success(decoded))
} catch {
return (.failure(error))
}
}
}
🔸 Command
Every service requests(e.g. GET/POST) is a specific comand for the presentation layer:
func products(completion: @escaping ((Result<InvestorProductsModel, Error>) -> Void)) throws {
let userUrl = baseUrl?.appendingPathComponent(MCConstants.Command.products)
guard let url = userUrl else {
completion(.failure(MCServiceError.couldNotCreate(url: userUrl?.absoluteString)))
return
}
let request = { () -> MCURLRequest in
MCURLRequest
.get(url: url)
.appendingHeaders([MCConstants.Headers.authorization: "\(MCConstants.Headers.bearer) \(authToken)"])
}
try makeRequest(request(),
map: InvestorProductsModel.self,
completion: completion)
}
🔸 URLSession
URLSession is built over protocols
struct MCURLSession: MCURLSessionProtocol {
private let session: URLSession
init(urlSession: URLSession = URLSession.shared) {
session = urlSession
}
func dataTask(with request: URLRequest, completion: @escaping (Data?, URLResponse?, Error?) -> Void) {
let task = session.dataTask(with: request) { responseData, urlResponse, responseError in
completion(responseData, urlResponse, responseError)
}
task.resume()
}
}
struct MCURLService {
private let session: MCURLSessionProtocol
private let dispatcher: Dispatcher
init(session: MCURLSessionProtocol = MCURLSession(),
dispatcher: Dispatcher = DefaultDispatcher()) {
self.session = session
self.dispatcher = dispatcher
}
}
extension MCURLService: MCURLServiceProtocol {
func performTask(with request: URLRequest,
completion: @escaping (Data?, URLResponse?, Error?) -> Void) {
session.dataTask(with: request) { responseData, urlResponse, responseError in
self.dispatcher.dispatch {
completion(responseData, urlResponse, responseError)
}
}
}
}
Each section is built over 4 files
- Router (routing layer)
- Presenter (view logic)
- Interactor (business logic for a use case)
- View (display data)
The routing layer performs the injection:
🔸 Presenter
🔸 View
🔸 Interactor
struct ProductsRouter {
let view: ProductsViewController?
init(sessionConfig: MCURLConfiguration) {
view = UIStoryboard(name: "Main",
bundle: nil)
.instantiateViewController(withIdentifier: "productsViewController") as? ProductsViewController
let serviceFacade = MCURLServiceFacade(configuration: sessionConfig)
let interactor = InvestorProductsInteractor(service: serviceFacade)
let presenter = ProductsPresenter(view: view,
productsInteractor: interactor,
configuration: sessionConfig)
interactor.presenter = presenter
view?.presenter = presenter
}
}
... building the main layers of the application:
🔸 View
view = UIStoryboard(name: "Main",
bundle: nil)
.instantiateViewController(withIdentifier: "productsViewController") as? ProductsViewController
🔸 Service facade
let serviceFacade = MCURLServiceFacade(configuration: sessionConfig)
🔸 Interactor
let interactor = InvestorProductsInteractor(service: serviceFacade)
🔸 Presenter
let presenter = ProductsPresenter(view: view,
productsInteractor: interactor,
configuration: sessionConfig)
}
-
View calls Presenter:
override func viewDidLoad() { super.viewDidLoad() presenter?.investorProducts() } -
Presenter performs Interactor call
func investorProducts() { productsInteractor.perform() } -
Interactor executes "business logic" and notifies Presenter
func perform() { performTry({ try service.products() { result in switch result { case .success(let response): self.presenter?.investor(products: response) case .failure(let error): if error.nsError.code == 401 { self.presenter?.logout() return } self.presenter?.on(error: error) } } }, fallback: { self.presenter?.on(error: $0) }) } -
Presenter revices data from interactor and notifies the view
func investor(products: InvestorProductsModel) { view?.load(user: configuration.keychain.userSession()?.user ?? UserModel(), products: products) } -
View updates the UI
func load(user: UserModel, products: InvestorProductsModel) { self.userNameLabel?.text = "Hello \(user.username)" self.planValueLabel?.text = products.totalPlanValue.priceValue self.products = products.products }
Each module is unit tested (mocks oriented): decoding, mapping, services, presenter, interactor and view (and utilies for sure).
- Presenter sample test
func testInvestorProductFetched() {
keychain?.userSessionHandler = {
let user = UserModel(firstName: "firstname",
lastName: "lastname",
email: "email",
mobileNumber: "000")
let session = UserSessionModel(bearerToken: "")
return LoginModel(user: user,
session: session)
}
view?.loadUserProductsHandler = {
XCTAssertEqual($0.firstName, "firstname")
XCTAssertEqual($0.lastName, "lastname")
XCTAssertEqual($0.email, "email")
XCTAssertEqual($0.mobileNumber, "000")
XCTAssertEqual($1.totalPlanValue, 1.0)
}
let model = InvestorProductsModel(totalPlanValue: 1.0,
products: [])
sut?.investor(products: model)
XCTAssertEqual(view?.counterLoadUserProducts, 1)
}
- Interactor sample test
func testPerformShouldReturnInvestorProducts() {
presenter?.investorFetchedProducts = {
XCTAssertNotNil($0)
}
guard let data = JSONMock.loadJson(fromResource: "valid_investor_products") else {
XCTFail("JSON data error!")
return
}
let session = MockedSession(data: data, response: nil, error: nil) { _ in }
create(session)
sut?.perform()
XCTAssertEqual(presenter?.counterInvestorFetchedProducts, 1)
XCTAssertEqual(presenter?.counterOnError, 0)
XCTAssertEqual(presenter?.counterLogout, 0)
}
- Request sample tests
func testInvestorProductsRequest() {
keychain?.userSessionHandler = {
let user = UserModel(firstName: "",
lastName: "",
email: "",
mobileNumber: "")
let session = UserSessionModel(bearerToken: "TsMWRkbrcu3NGrpf84gi2+pg0iOMVymyKklmkY0oI84=")
return LoginModel(user: user,
session: session)
}
guard let data = JSONMock.loadJson(fromResource: "valid_investor_products") else {
XCTFail("JSON data error!")
return
}
let session = MockedSession(data: data, response: nil, error: nil) {
XCTAssertEqual($0.url?.absoluteString, "https://api-test02.moneyboxapp.com/investorproducts")
XCTAssertEqual($0.httpMethod, "GET")
let headers = $0.allHTTPHeaderFields
XCTAssertEqual(headers?["AppId"], "8cb2237d0679ca88db6464")
XCTAssertEqual(headers?["Content-Type"], "application/json")
XCTAssertEqual(headers?["appVersion"], "7.10.0")
XCTAssertEqual(headers?["apiVersion"], "3.0.0")
XCTAssertEqual(headers?["Authorization"], "Bearer TsMWRkbrcu3NGrpf84gi2+pg0iOMVymyKklmkY0oI84=")
XCTAssertNil($0.httpBody)
}
do {
try MCURLServiceFacade(configuration: configure(session))
.products { _ in }
} catch { XCTFail("Unexpected error \(error)!") }
}
- Response sample tests
func testInvestorProductsResponseShouldSuccess() {
guard let data = JSONMock.loadJson(fromResource: "valid_investor_products") else {
XCTFail("JSON data error!")
return
}
let session = MockedSession(data: data, response: nil, error: nil) { _ in }
do {
try MCURLServiceFacade(configuration: configure(session))
.products { result in
switch result {
case .success(let response):
XCTAssertEqual(response.totalPlanValue, 5651.960000)
let userProduct = response.products.first
XCTAssertEqual(userProduct?.planValue, 2693.80)
XCTAssertEqual(userProduct?.moneybox, 0.00)
XCTAssertEqual(userProduct?.product.friendlyName, "Stocks & Shares ISA")
case .failure(let error):
XCTFail("Should be success! Got: \(error)")
}
}
} catch { XCTFail("Unexpected error \(error)!") }
}
• Xcode 12
• iOS 13+