WWDC Party Intro to CoreStore

Transcript

1. MY JOURNEY TAMING CORE DATA AN INTRO TO THE CORESTORE LIBRARY WWDC PARTY - OPEN SOURCE GET TOGETHER JOHN ESTROPIA
2. ▸ @JohnEstropia ▸ Principal Engineer @ (Tokyo) ▸ OSS ABOUT ME http://github.com/JohnEstropia/CoreStore
3. WHAT I WON'T TEACH YOU ▸ Core Data
4. WHAT I'LL TALK ABOUT TODAY ▸ How I approached everyone's hate of Core Data ▸ Some CoreStore tricks to do common object persistence tasks
5. DEVS VERSUS CORE DATA
6. A LOT OF IOS DEVS HATE CORE DATA ▸ Not an understatement
7. A LOT OF IOS DEVS HATE CORE DATA ▸ Not an understatement
8. THE REASON? ▸ Speed? ▸ It's fast ▸ Database integrity? ▸ battle-tested for years ▸ Memory footprint? ▸ good lazying and caching mechanism ("faulting")
9. THE ACTUAL REASON ▸ Arguably the steepest learning curve among all iOS frameworks UIKit Core Data
10. CORE DATA:
11. HOW DEVS COPED
12. OTHERS: WROTE CORE DATA WRAPPERS ▸ Their approach: ▸ hide as much complexity as possible ▸ Syntax sugars ▸ Problems: ▸ Too much magic ▸ API users become too spoiled (pitfalls)
13. REALM: BUILT THEIR OWN SOLUTION ▸ Realm's primary marketing: ▸ "an alternative to SQLite and Core Data" ▸ Good API, fast database ▸ Issues: ▸ Some areas still need catching up (e.g. Migrations/ Versioning) ▸ Realm developers have proven they can catch up
14. ME: ALSO WROTE A CORE DATA WRAPPER ▸ CoreStore's approach: ▸ Make things easier, but just enough to keep users aware of pitfalls
15. safe but stagnant ❌ safe but open to expert options ✅
17. BUT WHY NOT JUST USE REALM? ▸ I started writing CoreStore in 2015 (Swift 1 beta) ▸ about 1 year before Realm was released
18. BUT WHY NOT JUST USE REALM? ▸ This is not a "Which is better?" debate ▸ If speed is a must, go with Realm ▸ I like Core Data's completeness as an Object Graph Manager
19. THIS GUY PROBABLY JUST DOESN'T WANT TO TRY REALM ▸ Well... ▸ https://realm.io/addons/ https://github.com/eure/RealmIncrementalStore
21. BUT I DIGRESS...
22. CORESTORE TAMING CORE DATA
23. CORE DATA ISSUE 1: CROSS-THREAD CONSISTENCY ▸ CoreStore enforces transaction-based updates ▸ Main thread objects are read-only ▸ No way to save edits except inside transactions ▸ 3 kinds of Transactions ▸ Asynchronous ▸ Synchronous ▸ Unsafe
24. CORESTORE TRANSACTIONS
25. CORESTORE TRANSACTIONS
26. CORE DATA ISSUE 2: TYPO-SENSITIVE QUERIES ▸ CoreStore's syntax are all type-safe and concise
27. VANILLA CORE DATA FETCH
28. CORESTORE FETCH
29. VANILLA CORE DATA QUERIES
30. CORESTORE QUERIES
31. CORE DATA ISSUE 3: TEDIOUS MODELS ▸ Xcode model editor and NSManagedObject ▸ Need to sync *.xcdatamodeld (XML) files and NSManagedObject subclass source files ▸ CoreStore has a pure-swift way to create models
32. CORESTOREOBJECT
33. CORESTOREOBJECT: NO MORE XML FILES!
34. CORE DATA ISSUE 4: MODEL VERSIONING HAS INCREASING COST
35. CORE DATA ISSUE 4: MODEL VERSIONING HAS INCREASING COST
36. CORE DATA ISSUE 4: MODEL VERSIONING HAS INCREASING COST
37. CORE DATA ISSUE 4: MODEL VERSIONING HAS INCREASING COST ▸ CoreStore offers Progressive Migrations ▸ Just worry about the latest migration every time
38. CORESTORE PROGRESSIVE MIGRATIONS (*.XCDATAMODELD) LINEAR
39. CORESTORE PROGRESSIVE MIGRATIONS (*.XCDATAMODELD) CUSTOM
40. CORESTOREOBJECT VERSIONING EXAMPLE VERSION 1
41. CORESTOREOBJECT VERSIONING EXAMPLE VERSION 1 VERSION 2
42. CORESTOREOBJECT VERSIONING EXAMPLE
43. CORESTOREOBJECT VERSIONING EXAMPLE
44. WHAT IF I ACCIDENTALLY EDIT A CLASS? COPY THE LOGGED "VERSION LOCKS"
45. VERSIONLOCKS RUNTIME ASSERTION-CHECKED
46. AND OTHER FEATURES ▸ Type-safe observers for objects and lists ▸ a backwards compatible port of DiffableSources API that works on iOS 11 and iOS 12 ▸ Efficient importing utilities ▸ custom sources (e.g. JSON) ▸ uniquing ▸ Support for 3rd-party logging frameworks
47. THANKS! @JohnEstropia