Swift Code Reuse Made Simple

What is the difference between static and dynamic libraries? Between libraries and frameworks? Between libraries and modules? How to manage the code by splitting it reusable chunks?
These and some other questions are answered in this presentation.

Presented at SwiftHeroes 2019 in Italy, Turin, on 15th of November.

Transcript

1. Swift code reuse made simple modules, packages, libraries
2. @aronskaya • macOS Engineer at MacPaw • CleanMyMac
3. Hoover
4. Fixel
5. @aronskaya • macOS Chapter Lead at Women Who Code Kyiv • workshop mentor at SwiftAveiro • one of founders of MacPaw Tech Talks
6. Swift code reuse made simple modules, packages, libraries
8. Behind this talk 1⃣ projects with 1 target
9. Behind this talk 1⃣ projects with 1 target apps, containing several apps
10. Behid this talk 1⃣ projects with 1 target apps, containing several apps C++ libraries, shared with Linux
11. Behid this talk 1⃣ projects with 1 target apps, containing several apps C++ libraries, shared with Linux projects with dozens internal libs
12. 1 app == 27 projects up to 14 targets per project
13. Agenda ⁉ Why separate codebase
14. Agenda ⁉ Why separate codebase How to do it: static, dylibs, frameworks, modules
15. Agenda ⁉ Why separate codebase How to do it: static, dylibs, frameworks, modules Dependency management: CocoaPods, Swift Package Manager
16. Agenda ⁉ Why separate codebase How to do it: static, dylibs, frameworks, modules Takeaways: best practices & modern approach Dependency management: CocoaPods, Swift Package Manager
17. Why
21. Faster compilation
22. Faster app launch
23. Smaller app bundle
24. ⌚ Easily support new platforms
25. Grow your GitHub
26. Test once use again and again
27. Learn&Train to think bigger
28. How Apple does it
29. How Apple does it
30. How Apple does it 172
31. Programmer evolution
32. Programmer evolution it works!
33. Programmer evolution it works! it works & is grouped in classes
34. Programmer evolution it works! it works & is grouped in classes it works & is grouped in reusable classes
35. Programmer evolution it works! it works & is grouped in classes it works & is grouped in reusable classes it works & grouped in a reusable module
36. The Versus Quiz
37. Static Dynamic
38. Static linking / libraries
39. Static library
40. Amazing Notes app
41. Amazing Notes app
43. Dynamic linking / libraries
44. Dynamic library dylib
45. Library Framework
49. Library Conceptually Technically ❌ doesn't affect the lifecycle of our app or objects 1⃣ a file (+ header files) can be dynamic or static Conceptual examples: CocoaLumberjack, SDWebImage, AFNetworking Technical example: stdlib
50. dylib
51. Framework Conceptually Technically ↺ affects the lifecycle of our app or objects a directory with at least 1 dylib is basically a dylib with bells & whistles Example: UIKit (we build our logic based on delegate callbacks— SceneDelegate, AppDelegate, UITableViewDelegate
53. Recap Static library headers + code, embedded into client's executable Dynamic library headers + code in a separate file Framework dynamic library + resources
54. Library Module
55. –Access Control—The Swift Programming Language docs “A module is a single unit of code distribution—a framework or application that is built and shipped as a single unit and that can be imported by another module with Swift’s import keyword.”
56. –Access Control—The Swift Programming Language docs “A module is a single unit of code distribution—a framework or application that is built and shipped as a single unit and that can be imported by another module with Swift’s import keyword.”
57. Module is just another type of header
58. ❌Implementation
59. ❌Implementation The impl lives in a static or a dynamic library
60. 2 Types of Modules
61. 2 Types of Modules Clang module •Objective-C, Swift… •module.modulemap
62. 2 Types of Modules Clang module Swift module •Objective-C, Swift •module.modulemap •Swift only •.swiftdoc, .swiftmodule
63. Swift Package Manager CocoaPods
64. SPM vs CocoaPods Swift ✅ Objective-C Xcode integration Multi platform support Resources
65. SPM vs CocoaPods Swift ✅ ✅ Objective-C Xcode integration Multi platform support Resources
66. SPM vs CocoaPods Swift ✅ ✅ Objective-C ✅ Xcode integration Multi platform support Resources
67. SPM vs CocoaPods Swift ✅ ✅ Objective-C ✅ ⏳ Xcode integration Multi platform support Resources
68. SPM vs CocoaPods Swift ✅ ✅ Objective-C ✅ ⏳ Xcode integration ❌ Multi platform support Resources
69. SPM vs CocoaPods Swift ✅ ✅ Objective-C ✅ ⏳ Xcode integration ❌ ✅ Multi platform support Resources
70. SPM vs CocoaPods Swift ✅ ✅ Objective-C ✅ ⏳ Xcode integration ❌ ✅ Multi platform support ❌ Resources
71. SPM vs CocoaPods Swift ✅ ✅ Objective-C ✅ ⏳ Xcode integration ❌ ✅ Multi platform support ❌ ✅ Resources
72. SPM vs CocoaPods Swift ✅ ✅ Objective-C ✅ ⏳ Xcode integration ❌ ✅ Multi platform support ❌ ✅ Resources ✅
73. SPM vs CocoaPods Swift ✅ ✅ Objective-C ✅ ⏳ Xcode integration ❌ ✅ Multi platform support ❌ ✅ Resources ✅ ⏳
75. –Serg Krivoblotsky, my college “I think, SPM is the most convenient Dependency Manager on the market. And Xcode integration makes it a dream. You paste a GitHub link—and you're in game!”
76. –Serg Krivoblotsky, my college “I think, SPM is the most convenient Dependency Manager on the market. And Xcode integration makes it a dream. You paste a GitHub link—and you're in game!”
82. Takeaways
83. Code Reuse Evolution ⭐ Static libs →
84. Code Reuse Evolution ⭐ Static libs → ⭐⭐ Dynamic libs →
85. Code Reuse Evolution ⭐ Static libs → ⭐⭐ Dynamic libs → ⭐⭐⭐ Frameworks, Modules →
86. Code Reuse Evolution ⭐ Static libs → ⭐⭐ Dynamic libs → ⭐⭐⭐ Frameworks, Modules → ⭐⭐⭐⭐ Swift Packages
87. Triggers: when separate code
88. Triggers: when separate code 1. You have files included in several targets
89. Triggers: when separate code 1. You have files included in several targets 2. You have a group of classes, that work together to provide a single piece of functionality
90. What to put in a separate lib? •Networking logic
91. What to put in a separate lib? •Networking logic •Foundation enhancements
92. What to put in a separate lib? •Networking logic •Foundation enhancements •Trial limitations
93. What to put in a separate lib? •Networking logic •Foundation enhancements •Trial limitations •Working with database
94. What to put in a separate lib? •Networking logic •Foundation enhancements •Trial limitations •Working with database • Analytics
95. What to put in a separate lib? •Networking logic •Foundation enhancements •Trial limitations •Working with database • Analytics •Every new feature
96. It is to have a library per each feature
97. It is to have a library per each feature Not 70
98. Tips on designing an interface • Allow flexible configuration (pass it in parameters, don’t try to guess what the client wants) init(param1:param2:param3:param4:)
99. Tips on designing an interface • Allow also simple default setup (have little or no parameters) init()
100. Tips on designing an interface • Allow asynchronous execution func execute(param0:param1:completionHandler:)
101. Tips on designing an interface • Use Apple Frameworks as example func tableView(_ tableView: UITableView, didDeselectRowAt indexPath: IndexPath)
102. Tips on designing an interface • Use famous and popular libraries and frameworks as examples
103. What to use if I start a project today?
104. What to use if I start a project today? Frameworks
105. What to use if I start a project today? Swift Package Manager
106. Thank you! iaronskaya Q&A