Andrea-Scuderi

import Combine
import Foundation

enum APIError: Error {
    case invalidBody
    case invalidEndpoint
    case invalidURL
    case emptyData
    case invalidJSON
    case invalidResponse

Andrea-Scuderi

MOUNT_ROOT=$(shell pwd)
DOCKER_TAG=emerge:1.0.0

docker_build:
	docker build --tag $(DOCKER_TAG) .

docker_bash:
	docker run \
			-it \
			--rm \

Andrea-Scuderi

FROM python:3.9.9-slim-buster

RUN apt-get -qq update
RUN apt-get install -qqy graphviz graphviz-dev gcc
RUN rm -rf /var/lib/apt/lists/*

RUN pip install --upgrade pip
RUN pip install emerge-viz

Andrea-Scuderi

import XCTest
import Foundation
import Combine

@testable import CombineAPIDemo

class Mocks {
    let user = User(name: "name",
                    email: "email",
                    password: "password",

Andrea-Scuderi

func testCreate() {

        //Setup fixture
        let usersURL = URL(string: APIDemo.baseURL + "/users")
        URLProtocolMock.testURLs = [usersURL: Data(Fixtures.createUserResponse.utf8)]
        
        //1) When is valid
        APIDemo.publisher = customPublisher
        URLProtocolMock.response = mocks.validResponse
        let publisher = APIDemo.create(user: self.mocks.user)

Andrea-Scuderi

 func evalValidResponseTest<T:Publisher>(publisher: T?) -> (expectations:[XCTestExpectation], cancellable: AnyCancellable?) {
        XCTAssertNotNil(publisher)
        
        let expectationFinished = expectation(description: "finished")
        let expectationReceive = expectation(description: "receiveValue")
        let expectationFailure = expectation(description: "failure")
        expectationFailure.isInverted = true
        
        let cancellable = publisher?.sink (receiveCompletion: { (completion) in
            switch completion {

Andrea-Scuderi

import Foundation

//References:
//  --: https://www.hackingwithswift.com/articles/153/how-to-test-ios-networking-code-the-easy-way
//  --: https://nshipster.com/nsurlprotocol/

@objc class URLProtocolMock: URLProtocol {
    // this dictionary maps URLs to test data
    static var testURLs = [URL?: Data]()
    static var response: URLResponse?

Andrea-Scuderi

import Cocoa
import Foundation

let baseURL = "http://localhost:8080"

enum APIError: Error {
    case invalidBody
    case invalidEndpoint
    case invalidURL
    case emptyData

Andrea-Scuderi

// Refactoring of the URLRequest with dataTask avoiding Throws using fatalError
func buildCreateUserURLRequest(user: User) -> URLRequest {
    let headers = [
        "Content-Type": "application/json",
        "cache-control": "no-cache",
    ]
    let encoder = JSONEncoder()
    guard let postData = try? encoder.encode(user) else {
        fatalError("APIError.invalidBody")
    }

Andrea-Scuderi

// Combining login and postTodo in a single call
func post(email: String, password: String, todo: Todo) -> AnyPublisher<Todo, Error>? {
    return login(email: email, password: password)
        .map {  token -> String in
            return token.string
        }
        .flatMap { (token) -> AnyPublisher<Todo, Error> in
            return postTodo(authToken: token, todo: todoList[1])
        }
        .eraseToAnyPublisher()