CocoaPods Dependency Resolution

This is a talk I gave at Stripe on the work I've done building Molinillo, the new CocoaPods dependency resolver. The page detailing the event is at https://stripe.com/blog/open-source-retreat-meetup, and the source for this presentation is at https://github.com/segiddins/Stripe-OSR-Talk.

A video is available at https://www.youtube.com/watch?v=-vMLpUD2Jw0.

Transcript

1. COCOAPODS DEPENDENCY RESOLUTION: INTRODUCING Molinillo SAMUEL E. GIDDINS @SEGIDDINS
3. RELEASES 0.34.0.RC1, 0.34.0, 0.34.1, 0.34.2, 0.34.4
4. Molinillo DEPENDENCY RESOLUTION GEM
5. BUT FIRST, A DETOUR
6. THE PODSPEC Pod::Spec.new do |s| s.name = 'PromiseKit-AFNetworking' s.version = '0.1.4' s.dependency 'AFNetworking', '~> 2.0' s.dependency 'PromiseKit/Promise' end
7. THE PODFILE source 'https://github.com/CocoaPods/Specs' platform, :ios, '8.1' pod 'AFNetworking', '< 1.3' pod 'RestKit', '~> 0.23.0' pod 'SEGModules', git: 'https://github.com/segiddins/SEGModules.git'
8. HOW IT WORKS
9. ENCAPSULATION ▸ SpecificationProvider ▸ UI
10. THE ALGORITHM ▸ Constrainst Solving Problem ▸ Backtracking ▸ Forward Checking
11. STACK OF States AND ➿
12. SORT DEPENDENCIES HANDLE ONE CREATE A POSSIBILITY STATE
13. SEE IF IT WORKS
14. YES => MOVE ON NO => UNWIND FOR CONFLICT
15. STOP WHEN ALL REQUIREMENTS ARE ACTIVATED
16. RAISE WHEN THERE ARE NO POSSIBIBLE STATES LEFT
17. EXAMPLES
18. platform :ios, "7.0" inhibit_all_warnings! pod 'RestKit' pod 'AFNetworking', '~> 1.2.0' Before: [!] Unable to satisfy the following requirements: - `AFNetworking (~> 1.3.0)` required by `RestKit/Network (0.23.3)` - `AFNetworking (~> 1.2.0)` required by `Podfile`
19. platform :ios, "7.0" inhibit_all_warnings! pod 'RestKit' pod 'AFAmazonS3Client' pod 'CargoBay' pod 'AFOAuth2Client' Before: [!] Unable to satisfy the following requirements: - `AFNetworking (~> 1.3.0)` required by `RestKit/Network (0.23.3)` - `AFNetworking (~> 1.2.0)` required by `Podfile`
20. platform :ios, "7.0" inhibit_all_warnings! pod 'AFAmazonS3Client' pod 'CargoBay' pod 'AFOAuth2Client' Before: [!] Unable to satisfy the following requirements: - `AFNetworking (~> 2.0)` required by `AFAmazonS3Client (2.0.0)` - `AFNetworking/Serialization` required by `AFNetworking (2.4.1)` - `AFNetworking/Security` required by `AFNetworking (2.4.1)` - `AFNetworking/Reachability` required by `AFNetworking (2.4.1)` - `AFNetworking/NSURLConnection` required by `AFNetworking (2.4.1)` - `AFNetworking/NSURLSession` required by `AFNetworking (2.4.1)` - `AFNetworking/UIKit` required by `AFNetworking (2.4.1)` - `AFNetworking/Serialization` required by `AFNetworking/NSURLConnection (2.4.1)` - `AFNetworking/Reachability` required by `AFNetworking/NSURLConnection (2.4.1)` - `AFNetworking/Security` required by `AFNetworking/NSURLConnection (2.4.1)` - `AFNetworking/Serialization` required by `AFNetworking/NSURLSession (2.4.1)` - `AFNetworking/Reachability` required by `AFNetworking/NSURLSession (2.4.1)` - `AFNetworking/Security` required by `AFNetworking/NSURLSession (2.4.1)` - `AFNetworking/NSURLConnection` required by `AFNetworking/UIKit (2.4.1)` - `AFNetworking/NSURLSession` required by `AFNetworking/UIKit (2.4.1)` - `AFNetworking (~> 2.2)` required by `CargoBay (2.1.0)` - `AFNetworking (~> 1.3)` required by `AFOAuth2Client (0.1.2)`
21. After: it just works !
22. ! STRIPE ! ❤
23. SAMUEL E. GIDDINS COCOAPODS CORE TEAM @SEGIDDINS