A journey towards Frameworks and Swift

The exciting journey of changing your project architecture basing it on Frameworks and allowing developers to start using Swift in the SoundCloud main app.

Since the launch of Swift in 2014 we had used Swift only in the SoundCloud watch app. The need of having reusable business logic among other reasons led to a new architecture for the project based on dynamic frameworks where Swift would be a first citizen member. In this talk we'll explain the approach we followed at SoundCloud to change our app architecture allowing developers to start using Swift in the project. Learnings, caveats, and how the project and the company has benefit from this journey.

Transcript

1. A journey into Frameworks and Swift September 2016
2. Pedro Piñera @pepibumur pepi@soundcloud.com Matej Balantič @skavt matej@soundcloud.com
9. • Architecture • Test coverage • Coupled • From iOS 3
11. • Reactive • Fully tested • Reusable code
13. Reusing code Local pods Podfile
14. CocoaPods && !Versioning Conflicts changing between branches 1
15. Messy Dependency Graph Too many horizontal dependencies 2
19. Everyone touching everything Conflicts everywhere
20. Growing platforms 2007 2016
21. Scaling up the team
22. Scaling up the team
24. Swift Platform Independent Reduce conflicts Compatible with all the Apple platforms: iOS, tvOS, macOS, watchOS Avoid unnecessary overhead when working with the new setup. Opportunity to start coding Swift. Objc public interface. Vertical dependencies Simple dependency graph that aims vertical dependency over horizontal. Goals
25. How?
26. iOS tvOS watchOS Core UI
27. iOS tvOS watchOS Core UI
28. iOS tvOS watchOS Core UI • Shared models. • Architectural components. • Tooling ◦ Accessing the Core Data ◦ Networking layer • Colors • Fonts • Custom Views
29. iOS tvOS watchOS Core UI API Config API Config • Base URL • HTTP Headers • Session token
30. iOS tvOS watchOS Core UI API Config API Config • Base URL • HTTP Headers • Session token Tooling
31. iOS tvOS watchOS Core UI Logging Analytics Fabric
32. Search iOS Core UI tvOS watchOS ...
33. Search iOS Core UI tvOS watchOS SearchiOS SearchtvOS ...
34. Search iOS Core UI tvOS watchOS Payments SearchiOS SearchtvOS Offline ...
35. Search iOS Core UI tvOS watchOS Payments SearchiOS SearchtvOS Offline ...
36. Are not reusable among platforms XIBs/Storyboards Platform reusability
37. FeatureCore (Business Logic) Platform independent feature Using frameworks FeatureiOS FeaturetvOS FeaturemacOS FeaturetvOS Feature
38. ⋁ ⋁ “A good target number of dynamic frameworks to have is about half a dozen.” WWDC 2016 - Optimizing Startup Time
39. FeatureCore (Business Logic) Platform independent feature Alternative: Using Macros Feature Presentation (Views in code)
40. Search iOS Core UI tvOS watchOS SearchiOS SearchtvOS Offline ... App Core Data Offline Database App Keychain
41. Search iOS UI tvOS watchOS SearchiOS SearchtvOS Offline ... App Core Data Offline Database App Keychain Core DB Wrapper
42. Search iOS UI tvOS watchOS SearchiOS SearchtvOS Offline ... App Core Data Offline Database App Keychain Core DB Wrapper Stream Stream Database
43. Benefits • Fully vertical features. ◦ Almost no dependendencies between teams. • Cleaner data models. Concerns • Migration time. • Deletion cascading. Alternatives • 1 shared with independent tables. • Dynamically generated merging models. Independent databases Each feature its own database
44. Tooling
45. Example projects To play with your Frameworks
46. Ensuring multi-platform compatibility With Fastlane Thanks Felix #yatusabes
47. Playgrounds Easy onboarding Thanks Apple #yatusabes
48. Epilogue (There’s no epilogue)
49. • Find if it works for you. ◦ Team structure/size? ◦ Supported platforms/targets? ◦ Need to enforce good practices? • Be aware of the downsides: ◦ Xcode still has a long way to go ◦ More than 6 dynamic frameworks are discouraged. Are Frameworks for me?
50. • Framework oriented programming Link • Library oriented programming Link • Building modern frameworks Link • How to create a Framework for iOS Link • The unofficial guide to xcconfig files Link • Static or dynamic libraries Link • Framework vs library Link • Micro Features Architecture for iOS Link This slides http://bit.ly/soundcloud-frameworks References
51. Gracias Questions? @skavt | @pepibumur (thanks to @LenartLeo for amazing journey map)