Thinking Outside The Box with Swift Package Manager - Hacking With Swift Live, Bath, UK, July 2019

A brief history of being able to use other people's code with your code, and then some examples of neat stuff you can do using SPM for things you'd normally have to do with bash.

Sample code: https://github.com/designatednerd/PanoramaRama

Transcript

1. THINKING OUTSIDE THE BOX WITH
   !
   SWIFT PACKAGE MANAGER
   HACKING WITH SWIFT LIVE | BATH, UK | JULY 2019
   BY ELLEN SHAPIRO | @DESIGNATEDNERD | APOLLOGRAPHQL.COM
   

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3. DRAGGING THINGS INTO PROJECTS
   

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4. UPDATES?
   (˽°□°҂˽Ɨ ˍʓˍ
   

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5. GIT SUBMODULES
   

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6. CHANGES?
   

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7. COCOAPODS
   

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9. !
   CARTHAGE
   

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10. CODE SIGNING
    !
    SILLINESS
    

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11. SWIFT PACKAGE MANAGER
    

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13. SERVER:
    

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14. SERVER:
    COMMAND LINE:
    

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15. SERVER:
    COMMAND LINE:
    IOS:
    

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17. !
    XCODE 11
    

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18. !
    BETA?!
    

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19. RIGHT NOW!
    

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20. Command line. Sorry.
    

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22. swift package init
    

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23. swift package init --type executable
    

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24. swift package init --type library
    

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25. swift package generate-xcodeproj
    

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26. swift build
    

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27. swift run
    

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28. swift run [project] [arguments]
    

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29. I HATE BASH
    

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30. I HATE BASH
    (I DON'T UNDERSTAND BASH)
    

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31. I HATE BASH
    (I AM VERY BAD AT BASH)
    

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32. TYPE SAFETY?
    

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33. !
    BETTER BUILD SCRIPT WRAPPERS
    

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34. RUN WHEN YOU BUILD YOUR MAIN PROJECT
    

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35. IN YOUR SPM EXECUTABLE PROJECT
    

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36. main.swift
    let args = CommandLine.arguments.dropFirst()
    print("Arguments: \(args)")
    if args.contains("--prebuild") {
    print("Run pre-build tasks")
    }
    if args.contains("--postbuild") {
    print("Run post-build tasks")
    }
    

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37. main.swift
    let args = CommandLine.arguments.dropFirst()
    print("Arguments: \(args)")
    if args.contains("--prebuild") {
    print("Run pre-build tasks")
    }
    if args.contains("--postbuild") {
    print("Run post-build tasks")
    }
    

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38. main.swift
    let args = CommandLine.arguments.dropFirst()
    print("Arguments: \(args)")
    if args.contains("--prebuild") {
    print("Run pre-build tasks")
    }
    if args.contains("--postbuild") {
    print("Run post-build tasks")
    }
    

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39. main.swift
    let args = CommandLine.arguments.dropFirst()
    print("Arguments: \(args)")
    if args.contains("--prebuild") {
    print("Run pre-build tasks")
    }
    if args.contains("--postbuild") {
    print("Run post-build tasks")
    }
    

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40. IN YOUR ACTUAL PROJECT
    

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41. IN YOUR ACTUAL PROJECT
    (EX: HTTPS://GITHUB.COM/DESIGNATEDNERD/PANORAMARAMA)
    

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44. <--- Main app
    <--- SPM executable
    

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45. PRE-BUILD SCRIPT
    cd Scripty
    swift run Scripty --prebuild
    

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46. PRE-BUILD SCRIPT
    cd Scripty
    swift run Scripty --prebuild
    POST-BUILD SCRIPT
    cd Scripty
    swift run Scripty --postbuild
    

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50. WHAT CAN I DO WITH THIS?
    

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51. HIDE AN OPEN-SOURCE PROJECT'S
    !
    BUILD SECRETS
    

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52. Environment.plist
    

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55. HTTPS://GITHUB.COM/DESIGNATEDNERD/
    PLISTER
    

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56. EnvironmentUpdater.swift
    import Files
    import Plister
    struct EnvironmentUpdater {
    static func updateEnvironment(file: File) throws {
    try Plister.setValue("I was updated!", for: "string_secret", in: file)
    }
    static func resetEnvironment(file: File) throws {
    try file.resetToGitHEAD()
    }
    }
    

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57. EnvironmentUpdater.swift
    import Files
    import Plister
    struct EnvironmentUpdater {
    static func updateEnvironment(file: File) throws {
    try Plister.setValue("I was updated!", for: "string_secret", in: file)
    }
    static func resetEnvironment(file: File) throws {
    try file.resetToGitHEAD()
    }
    }
    

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58. EnvironmentUpdater.swift
    import Files
    import Plister
    struct EnvironmentUpdater {
    static func updateEnvironment(file: File) throws {
    try Plister.setValue("I was updated!", for: "string_secret", in: file)
    }
    static func resetEnvironment(file: File) throws {
    try file.resetToGitHEAD()
    }
    }
    

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59. EnvironmentUpdater.swift
    import Files
    import Plister
    struct EnvironmentUpdater {
    static func updateEnvironment(file: File) throws {
    try Plister.setValue("I was updated!", for: "string_secret", in: file)
    }
    static func resetEnvironment(file: File) throws {
    try file.resetToGitHEAD()
    }
    }
    

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60. EnvironmentUpdater.swift
    import Files
    import Plister
    struct EnvironmentUpdater {
    static func updateEnvironment(file: File) throws {
    try Plister.setValue("I was updated!", for: "string_secret", in: file)
    }
    static func resetEnvironment(file: File) throws {
    try file.resetToGitHEAD()
    }
    }
    

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61. main.swift
    let args = CommandLine.arguments.dropFirst()
    let plistFile = try SourceFolders.appRoot.file(named: "Environment.plist")
    if args.contains("--prebuild") {
    print("Run pre-build tasks")
    try EnvironmentUpdater.updateEnvironment(file: plistFile)
    }
    if args.contains("--postbuild") {
    print("Run post-build tasks")
    try EnvironmentUpdater.resetEnvironment(file: plistFile)
    }
    

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62. main.swift
    let args = CommandLine.arguments.dropFirst()
    let plistFile = try SourceFolders.appRoot.file(named: "Environment.plist")
    if args.contains("--prebuild") {
    print("Run pre-build tasks")
    try EnvironmentUpdater.updateEnvironment(file: plistFile)
    }
    if args.contains("--postbuild") {
    print("Run post-build tasks")
    try EnvironmentUpdater.resetEnvironment(file: plistFile)
    }
    

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63. main.swift
    let args = CommandLine.arguments.dropFirst()
    let plistFile = try SourceFolders.appRoot.file(named: "Environment.plist")
    if args.contains("--prebuild") {
    print("Run pre-build tasks")
    try EnvironmentUpdater.updateEnvironment(file: plistFile)
    }
    if args.contains("--postbuild") {
    print("Run post-build tasks")
    try EnvironmentUpdater.resetEnvironment(file: plistFile)
    }
    

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65. main.swift
    let args = CommandLine.arguments.dropFirst()
    let plistFile = try SourceFolders.appRoot.file(named: "Environment.plist")
    if args.contains("--prebuild") {
    print("Run pre-build tasks")
    try EnvironmentUpdater.updateEnvironment(file: plistFile)
    }
    if args.contains("--postbuild") {
    print("Run post-build tasks")
    try EnvironmentUpdater.resetEnvironment(file: plistFile)
    }
    

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67. EnvironmentUpdater.swift
    import Files
    import Plister
    struct EnvironmentUpdater {
    static func updateEnvironment(file: File) throws {
    try Plister.setValue("I was updated!", for: "string_secret", in: file)
    }
    static func resetEnvironment(file: File) throws {
    try file.resetToGitHEAD()
    }
    }
    

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71. EnvironmentUpdater.swift
    static func updateEnvironment(file: File) throws {
    if
    let secretsFolder = SourceFolders.secrets,
    let secrets = try? secretsFolder.file(named: "production.json") {
    let json = try JSONLoader.loadJSONDictionary(from: secrets)
    try json.forEach { key, value in
    try Plister.setValue(value, for: key, in: file)
    }
    } else {
    let env = ProcessInfo.processInfo.environment
    guard let stringSecret = env["string_secret"] else {
    throw EnvironmentUpdater.EnvError.couldntLoadFromEnv
    }
    try Plister.setValue(stringSecret, for: "string_secret", in: file)
    }
    }
    

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72. EnvironmentUpdater.swift
    static func updateEnvironment(file: File) throws {
    if
    let secretsFolder = SourceFolders.secrets,
    let secrets = try? secretsFolder.file(named: "production.json") {
    let json = try JSONLoader.loadJSONDictionary(from: secrets)
    try json.forEach { key, value in
    try Plister.setValue(value, for: key, in: file)
    }
    } else {
    let env = ProcessInfo.processInfo.environment
    guard let stringSecret = env["string_secret"] else {
    throw EnvironmentUpdater.EnvError.couldntLoadFromEnv
    }
    try Plister.setValue(stringSecret, for: "string_secret", in: file)
    }
    }
    

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73. EnvironmentUpdater.swift
    static func updateEnvironment(file: File) throws {
    if
    let secretsFolder = SourceFolders.secrets,
    let secrets = try? secretsFolder.file(named: "production.json") {
    let json = try JSONLoader.loadJSONDictionary(from: secrets)
    try json.forEach { key, value in
    try Plister.setValue(value, for: key, in: file)
    }
    } else {
    let env = ProcessInfo.processInfo.environment
    guard let stringSecret = env["string_secret"] else {
    throw EnvironmentUpdater.EnvError.couldntLoadFromEnv
    }
    try Plister.setValue(stringSecret, for: "string_secret", in: file)
    }
    }
    

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75. CONTINUOUS INTEGRATION SERVERS
    

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76. EnvironmentUpdater.swift
    static func updateEnvironment(file: File) throws {
    if
    let secretsFolder = SourceFolders.secrets,
    let secrets = try? secretsFolder.file(named: "production.json") {
    let json = try JSONLoader.loadJSONDictionary(from: secrets)
    try json.forEach { key, value in
    try Plister.setValue(value, for: key, in: file)
    }
    } else {
    let env = ProcessInfo.processInfo.environment
    guard let stringSecret = env["string_secret"] else {
    throw EnvironmentUpdater.EnvError.couldntLoadFromEnv
    }
    try Plister.setValue(stringSecret, for: "string_secret", in: file)
    }
    }
    

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77. EnvironmentUpdater.swift
    static func updateEnvironment(file: File) throws {
    if
    let secretsFolder = SourceFolders.secrets,
    let secrets = try? secretsFolder.file(named: "production.json") {
    let json = try JSONLoader.loadJSONDictionary(from: secrets)
    try json.forEach { key, value in
    try Plister.setValue(value, for: key, in: file)
    }
    } else {
    let env = ProcessInfo.processInfo.environment
    guard let stringSecret = env["string_secret"] else {
    throw EnvironmentUpdater.EnvError.couldntLoadFromEnv
    }
    try Plister.setValue(stringSecret, for: "string_secret", in: file)
    }
    }
    

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79. DIDN'T TOUCH THE COMMAND LINE!
    

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80. WHAT ELSE CAN I DO?
    

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81. "Stringly-typed cdoe is a
    tribleee idae."
    

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82. "Stringly-typed code is a
    terrible idea."
    

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83. WHAT CAN WE DETERMINE AT BUILD TIME TO
    AVOID USING HARD-CODED STRINGS?
    

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84. GENERATE CODE FOR
    !
    ASSET CATALOGS
    

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85. BEFORE
    UIImage(named: "fragile")!
    UIColor(named: "uhoh")!
    

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86. GENERATE METHODS TO ACCESS
    !
    LOCALIZED STRINGS
    

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87. YourCode.swift
    NSLocalizedString("The key that will be displayed by default",
    "Some comment")
    

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88. YourCode.swift
    NSLocalizedString("The key that will be displayed by default",
    "Some comment")
    Base.lproj/Localizable.strings
    /* Some Comment */
    "The key that will be displayed by default" =
    "The key that will be displayed by default";
    

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89. YourCode.swift
    NSLocalizedString("The key that will be displayed by default",
    "Some comment")
    Base.lproj/Localizable.strings
    /* Some Comment */
    "The key that will be displayed by default" =
    "The key that will be displayed by default";
    nl.lproj/Localizable.strings
    /* Some Comment */
    "The key that will be displayed by default" =
    "De sleutel die standaard wordt weergegeven";
    

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90. YourCode.swift
    NSLocalizedString("default_key",
    "Some comment")
    Base.lproj/Localizable.strings
    /* Some Comment */
    "default_key" = "The key that will be displayed by default";
    nl.lproj/Localizable.strings
    /* Some Comment */
    "default_key" = "De sleutel die standaard wordt weergegeven";
    

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91. ✨
    GENERATE ENUMS!
    

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92. YourCode.swift
    LocalizedString(key: .default_key)
    Base.lproj/Localizable.strings
    /* Some Comment */
    "default_key" = "The key that will be displayed by default";
    nl.lproj/Localizable.strings
    /* Some Comment */
    "default_key" = "De sleutel die standaard wordt weergegeven";
    

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93. ✨
    GENERATE ENUMS!
    

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95. AFTER
    UIImage(from: .fragile)
    UIColor(from: .uhoh)
    

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96. THINGS I HAVE LEARNED
    THE HARD WAY
    (SO YOU DON'T HAVE TO)
    

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97. KEEP AS MUCH IN SWIFT AS POSSIBLE
    

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98. CREATE REUSABLE LIBRARIES
    

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99. CREATE PER-APP EXECUTABLES
    TO TAKE TAKE ADVANTAGE OF THOSE LIBRARIES
    

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100. TEST!
     

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101. LEVERAGE GIT
     

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102. !
     MARATHON
     

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103. swift-sh
     

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104. OBLIGATORY SUMMARY SLIDE
     

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105. OBLIGATORY SUMMARY SLIDE
     > Swift Package Manager can help you make your iOS
     Projects better today
     

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106. OBLIGATORY SUMMARY SLIDE
     > Swift Package Manager can help you make your iOS
     Projects better today
     > Move build scripts to swift and keep type safety
     

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107. OBLIGATORY SUMMARY SLIDE
     > Swift Package Manager can help you make your iOS
     Projects better today
     > Move build scripts to swift and keep type safety
     > Actually test your build scripts!
     

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108. OBLIGATORY SUMMARY SLIDE
     > Swift Package Manager can help you make your iOS
     Projects better today
     > Move build scripts to swift and keep type safety
     > Actually test your build scripts!
     > In Xcode 11, you should be able to use it for your main
     app and scripts in the same project.
     

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109. !
     

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110. LINKS!
     > It's time to use Swift Package Manager
     https://artsy.github.io/blog/2019/01/05/its-time-to-
     use-spm/
     > Marathon
     https://github.com/JohnSundell/Marathon
     > swift-sh
     https://github.com/mxcl/swift-sh
     

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