DittoCoreData Example

Demonstrates usage of DittoCoreData, a library for mirroring CoreData object graphs into a Ditto DB and vice-versa.

Getting Started

• Checkout this repo
• Install dependencies: pod install
• Open DittoCoreDataExample.xcworkspace
• Build & Run this app on 2 different iOS simulators

Whenever you add an item in one simulator instance, you should see it be synced over to the other instance (and vice-versa).

Play around with it, try adding more entities with different properties and relationships between them.

API Overview

The API is relatively simple, we have a single DCDMirror class (accompanied by some value types) that mirrors the CoreData object graph into a Ditto DB and vice versa. It takes a root managed object context, a Ditto instance, and an array of "bindings" that describe the mapping.

// Set up the CoreData stack:
let persistentContainer = /* ... */
let persistentStoreDescription = persistentContainer.persistentStoreDescriptions.first!
persistentStoreDescription.setOption(true as NSNumber, forKey: NSPersistentHistoryTrackingKey)
persistentStoreDescription.setOption(true as NSNumber, forKey: NSPersistentStoreRemoteChangeNotificationPostOptionKey)
persistentContainer.loadPersistentStores(...)

// Set up Ditto:
let ditto = /* ... */
ditto.isHistoryTrackingEnabled = true

// Create the mirror object:
let mirror = DCDMirror(ditto: ditto, managedObjectContext: persistentContainer.viewContext, bindings: [
    DCDBinding(entity: Flight.entity(), idAttributeName: "id"),
    DCDBinding(entity: Passenger.entity(), idAttributeName: "id"),
    // ...
])

// Register ad delegate (optional, only notification style methods for now):
mirror.delegate = self

That's it, the DCDMirror will take it from there.

In the provided example project, you can follow along with Persistence.swift and how it uses DCDMirror to replicate CoreData models.

Copyright

See LICENSE file in the root of this repo.