Palettes contains three NSIncrementalStore subclasses for loading data from various sources, including a local JSON file and a remote API endpoint. These stores are intended to be used independantly as examples for using Incremental Stores with Core Data.

Palettes is setup to work with data from the from the COLOURlovers API but the stores are simple enough to be adapted for other data formats. The JSON modeling is not central to the implementation.

LocalIncrementalStore provides the most basic building blocks and a disk based read-only Incremental Store.

RemoteIncrementalStore uses an API to provide JSON from a remote data source. This class can be without a Fetched Results Controller, and leverage NSAsynchronousFetchRequest for basic asynchronous request handling.

CachingIncrementalStore utilizes a second internal Core Data stack to serve requests from local cache while asynchronously updating from a remote data source. As remote objects are fetched, the local cache context is updated in addition to the main context. Using an NSFetchedResultsController is recommended for observing and responding to change notifications.

For more information, see the complete write up about Building an NSIncrementalStore.

Palettes is setup to use the CachingIncrementalStore by default. To change stores, modify the storeType passed into the NSPersistentStoreCoordinator, as it's initialized inside CoreDataManager.

• Xcode 13
• Swift 5

The MIT License (MIT)