Swift User Group - April 2016: Building Fabric.app in Swift

Collection to tidbits about the things I learned while building the Fabric app.

Transcript

1. Building Fabric.app in Swift
   "Building Fabric.app in Swift" - Javier Soto. April 2016 1
   

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2. Intro
   @Javi
   "Building Fabric.app in Swift" - Javier Soto. April 2016 2
   

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3. "Building Fabric.app in Swift" - Javier Soto. April 2016 3
   

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4. Outline
   4 What is Fabric.app?
   4 Tools used
   4 Architecture
   4 Better with Swift
   4 Error reporting
   "Building Fabric.app in Swift" - Javier Soto. April 2016 4
   

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5. What is Fabric.app?
   "Building Fabric.app in Swift" - Javier Soto. April 2016 5
   

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6. What is Fabric.app?
   "Building Fabric.app in Swift" - Javier Soto. April 2016 6
   

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7. What is Fabric.app?
   "Building Fabric.app in Swift" - Javier Soto. April 2016 7
   

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8. Tools
   "Building Fabric.app in Swift" - Javier Soto. April 2016 8
   

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9. Dependency management
   "Building Fabric.app in Swift" - Javier Soto. April 2016 9
   

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10. Dependency management
    4 SSL Pinning
    4 Keychain
    4 1Password integration
    4 Graphs
    4 Networking, caching
    "Building Fabric.app in Swift" - Javier Soto. April 2016 10
    

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11. Dependency management
    4 CocoaPods
    4 Carthage
    "Building Fabric.app in Swift" - Javier Soto. April 2016 11
    

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12. CocoaPods
    4 More widely adopted
    4 Less work to integrate frameworks
    4 Easily link some frameworks only in Debug
    "Building Fabric.app in Swift" - Javier Soto. April 2016 12
    

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13. Carthage
    4 Precompilation == Speed
    "Building Fabric.app in Swift" - Javier Soto. April 2016 13
    

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14. Swift Package Manager
    "Building Fabric.app in Swift" - Javier Soto. April 2016 14
    

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15. Interface Builder
    "Building Fabric.app in Swift" - Javier Soto. April 2016 15
    

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16. AutoLayout
    "Building Fabric.app in Swift" - Javier Soto. April 2016 16
    

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17. AutoLayout
    "Building Fabric.app in Swift" - Javier Soto. April 2016 17
    

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18. Storyboards
    "Building Fabric.app in Swift" - Javier Soto. April 2016 18
    

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19. UIStoryboard
    class UIStoryboard {
    func instantiateViewControllerWithIdentifier(_ identifier: String) -> UIViewController
    }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 19
    

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20. UIStoryboard
    let vc = mainStoryboard.instantiateViewControllerWithIdentifier("ApplicationOverviewID") as! ApplicationOverviewVC
    vc.userSession = ...
    vc.applicationID = ...
    "Building Fabric.app in Swift" - Javier Soto. April 2016 20
    

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21. UIStoryboard
    final class ApplicationOverviewVC {
    // I hope you like "!"s...
    var userSession: UserSession!
    var applicationID: String!
    func viewDidLoad() {
    super.viewDidLoad()
    self.userSession.foo()
    }
    }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 21
    

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22. Storyboards
    final class ApplicationOverviewVC {
    let userSession: UserSession
    let applicationID: String
    init(userSession: UserSession, applicationID: String) {
    self.userSession = userSession
    self.applicationID = applicationID
    super.init(nibName: ..., bundle: ...)
    }
    func viewDidLoad() {
    super.viewDidLoad()
    // Compile-time guarantee of object fully initialized
    self.userSession.foo()
    }
    }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 22
    

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23. Fastlane
    "Building Fabric.app in Swift" - Javier Soto. April 2016 23
    

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24. Fastlane
    - https://github.com/fastlane/examples
    "Building Fabric.app in Swift" - Javier Soto. April 2016 24
    

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25. ReactiveCocoa
    "Building Fabric.app in Swift" - Javier Soto. April 2016 25
    

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26. ReactiveCocoa
    self.accountService.muteAllNotifications(untilTime: date)
    "Building Fabric.app in Swift" - Javier Soto. April 2016 26
    

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27. ReactiveCocoa
    self.accountService.muteAllNotifications(untilTime: date)
    .continueWhenApplicationIsBackgrounded(taskName: "Muting notifications")
    "Building Fabric.app in Swift" - Javier Soto. April 2016 27
    

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28. Tools
    "Building Fabric.app in Swift" - Javier Soto. April 2016 28
    

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29. Architecture
    "Building Fabric.app in Swift" - Javier Soto. April 2016 29
    

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30. Architecture
    FabricAPI.framework
    "Building Fabric.app in Swift" - Javier Soto. April 2016 30
    

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31. Architecture
    4 Massive View Controllers
    4 View Models
    4 Glue-code View Controllers
    4 Table View Data sources
    "Building Fabric.app in Swift" - Javier Soto. April 2016 31
    

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32. Architecture
    GenericTableViewDataSource
    "Building Fabric.app in Swift" - Javier Soto. April 2016 32
    

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33. Architecture
    GenericTableViewDataSource
    protocol TableSectionType {
    associatedtype AssociatedTableRowType: TableRowType
    var rows: [AssociatedTableRowType] { get }
    var title: String? { get }
    }
    protocol TableRowType { }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 33
    

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34. Architecture
    GenericTableViewDataSource
    final class GenericTableViewDataSource
    SectionType: TableSectionType,
    RowType: TableRowType
    where SectionType.AssociatedTableRowType == RowType,
    SectionType: Equatable,
    RowType: Equatable>: NSObject, UITableViewDataSource
    "Building Fabric.app in Swift" - Javier Soto. April 2016 34
    

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35. Architecture
    GenericTableViewDataSource
    enum ProjectIssueRow: TableRowType, Equatable {
    case Loading
    case NoIssues
    case ErrorLoadingIssues
    case ProjectIssue(Issue)
    }
    return GenericTableViewDataSource(
    tableView: tableView,
    tableViewData: observableProperty, // Observable
    computeSections: { elements in ... }, /// Pure function from `Elements` to `[SectionType]`
    configureRow: { row, indexPath in ... } /// Function from `RowType` to `UITableViewCell`
    )
    "Building Fabric.app in Swift" - Javier Soto. April 2016 35
    

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36. Better with Swift
    "Building Fabric.app in Swift" - Javier Soto. April 2016 36
    

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37. Better with Swift
    4 Nullability
    4 Type-safe JSON parsing
    4 Code generation
    "Building Fabric.app in Swift" - Javier Soto. April 2016 37
    

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38. Nullability
    "Building Fabric.app in Swift" - Javier Soto. April 2016 38
    

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39. "Building Fabric.app in Swift" - Javier Soto. April 2016 39
    

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40. Nullability
    final class ApplicationListViewController: BaseFabricTableViewController
    "Building Fabric.app in Swift" - Javier Soto. April 2016 40
    

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41. Nullability
    final class ApplicationListViewController: BaseFabricTableViewController {
    override viewDidLoad() {
    super.viewDidLoad()
    let session = UserSession.currentUserSession
    if let session = session session {
    session.requestApplications()...
    }
    // or...
    session!.requestApplications()...
    }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 41
    

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42. Nullability
    final class ApplicationListViewController: BaseFabricTableViewController {
    init(viewModel: ApplicationListViewModel)
    }
    final class ApplicationListViewModel {
    init(fabricAPI: AuthenticatedFabricAPI)
    }
    public final class AuthenticatedFabricAPI {
    public init(authResponse: AuthResponse)
    }
    public final class AuthResponse {
    let accessToken: String
    }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 42
    

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43. "Building Fabric.app in Swift" - Javier Soto. April 2016 43
    

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44. Nullability
    final class ApplicationListViewModel {
    var applications: [Application]?
    }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 44
    

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45. Nullability
    enum DataLoadState {
    case Loading
    case Failed
    case Loaded(T)
    }
    final class ApplicationListViewModel {
    var applications: DataLoadState = .Loading
    }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 45
    

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46. Type-safe JSON parsing
    "Building Fabric.app in Swift" - Javier Soto. April 2016 46
    

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47. JSON Parsing Anti-Patterns
    public struct Application {
    public var ID: String?
    public var name: String?
    public var bundleIdentifier: String?
    public mutating func decode(j: [String: AnyObject]) {
    self.ID = j["id"] as? String
    self.name = j["name"] as? String
    self.bundleIdentifier = j["identifier"] as? String
    }
    }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 47
    

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48. JSON Parsing Anti-Patterns
    public struct Application {
    public let ID: String
    public let name: String
    public let bundleIdentifier: String
    public static func decode(j: [String: AnyObject]) -> Application? {
    guard let ID = j["id"] as? String,
    let name = j["name"] as? String,
    let bundleIdentifier = j["identifier"] as? String else { return nil }
    return Application(
    ID: ID,
    name: name,
    bundleIdentifier: bundleIdentifier
    )
    }
    }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 48
    

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49. Type-safe JSON parsing
    import Decodable /// https://github.com/Anviking/Decodable
    public struct Application: Decodable {
    public let ID: String
    public let name: String
    public let bundleIdentifier: String
    public static func decode(j: AnyObject) throws -> Application {
    return try Application(
    ID: j => "id",
    name: j => "name",
    bundleIdentifier: j => "identifier"
    )
    }
    }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 49
    

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50. Code Generation
    "Building Fabric.app in Swift" - Javier Soto. April 2016 50
    

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51. Code Generation
    /// Swift < 2.2
    UIBarButtonItem(barButtonSystemItem: .Done, target: self, action: Selector("buttonTapped"))
    // Swift 2.2
    UIBarButtonItem(barButtonSystemItem: .Done, target: self, action: #selector(ViewController.buttonTapped))
    "Building Fabric.app in Swift" - Javier Soto. April 2016 51
    

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52. Code Generation
    super.init(nibName: "ViewControllerNibName", bundle: nil)
    let nib = UINib(nibName: "NibName", bundle: nil)
    tableView.registerNib(nib, forCellReuseIdentifier: "ReuseIdentifier")
    let cell = tableView.dequeueReusableCellWithIdentifier("ReuseIdentifier", forIndexPath: indexPath) as! MyTableViewCell
    let image = UIImage(named: "ImageName")!
    "Building Fabric.app in Swift" - Javier Soto. April 2016 52
    

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53. Code Generation: R.swift
    https://github.com/mac-cain13/R.swift
    "Building Fabric.app in Swift" - Javier Soto. April 2016 53
    

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54. Code Generation: R.swift
    https://github.com/mac-cain13/R.swift
    4 Nibs
    4 Reuse Identifiers
    4 Image names in asset catalogs
    4 Other file names in the bundle
    "Building Fabric.app in Swift" - Javier Soto. April 2016 54
    

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55. Code Generation: R.swift
    https://github.com/mac-cain13/R.swift
    super.init(nibResource: R.nib.myViewController)
    class MyTableViewCell: UITableViewCell, ReusableNibTableViewCell {
    /// This will even fail to compile if it's not the right cell
    static let nibResource = R.nib.myTableViewCell
    }
    tableView.registerReusableNibCell(MyTableViewCell)
    let cell = MyTableViewCell.dequeueFromTableView(tableView, indexPath)
    let image = R.image.imageName
    "Building Fabric.app in Swift" - Javier Soto. April 2016 55
    

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56. Error Reporting
    "Building Fabric.app in Swift" - Javier Soto. April 2016 56
    

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57. Error Reporting
    do {
    try fileManager.createDirectoryAtPath(path, withIntermediateDirectories: true, attributes: nil)
    /// ...
    }
    catch {
    print("Error: \(error)")
    }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 57
    

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58. Error Reporting
    do {
    try fileManager.createDirectoryAtPath(path, withIntermediateDirectories: true, attributes: nil)
    /// ...
    }
    catch {
    Crashlytics.sharedInstance().recordError(error, withAdditionalUserInfo: userInfo)
    }
    "Building Fabric.app in Swift" - Javier Soto. April 2016 58
    

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59. Error Reporting
    "Building Fabric.app in Swift" - Javier Soto. April 2016 59
    

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60. Questions?
    4 @Javi
    4 javi@twitter.com
    4 fabric-app-ios@twitter.com
    "Building Fabric.app in Swift" - Javier Soto. April 2016 60
    

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61. Thanks !
    "Building Fabric.app in Swift" - Javier Soto. April 2016 61
    

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