contentful-persistence.swift

// Tell the library which of your `NSManagedObject` subclasses that conform to `EntryPersistable` should be used when mapping API responses to CoreData entities.
let entryTypes = [Author.self, Category.self, Post.self]

// Initialize the data store and it's schema.
let store = CoreDataStore(context: self.managedObjectContext)
let persistenceModel = PersistenceModel(spaceType: SyncInfo.self, assetType: Asset.self, entryTypes: entryTypes)

// Initialize the Contentful.Client with a persistenceIntegration which will receive messages about changes when calling `sync methods`
self.client = Client(spaceId: "<YOUR_SPACE_ID>", accessToken: "<YOUR_ACCESS_TOKEN>")

// Create the manager.
self.syncManager = SynchronizationManager(
    client: self.client,
    localizationScheme: LocalizationScheme.all, // Save data for all locales your space supports.
    persistenceStore: self.store,
    persistenceModel: persistenceModel
)

// Sync with the API.
self.syncManager.sync { _ in
  do {
    // Fetch all `Posts` from CoreData
    let post: Post? = try self.store.fetchAll(type: Post.self, predicate: NSPredicate(value: true))
  } catch {
    // Handle error thrown by CoreData fetches.
  }
}

class SyncInfo: NSManagedObject, SyncSpacePersistable {
    @NSManaged var syncToken: String?
    @NSManaged var dbVersion: NSNumber?
}

class Asset: NSManagedObject, AssetPersistable {
    @NSManaged var id: String
    @NSManaged var localeCode: String?
    @NSManaged var title: String?
    @NSManaged var assetDescription: String?
    @NSManaged var urlString: String?
    @NSManaged var createdAt: Date?
    @NSManaged var updatedAt: Date?

    @NSManaged var size: NSNumber?
    @NSManaged var width: NSNumber?
    @NSManaged var height: NSNumber?
    @NSManaged var fileType: String?
    @NSManaged var fileName: String?
}

import Foundation
import CoreData
import ContentfulPersistence
import Contentful

// The following @objc attribute is only necessary if your xcdatamodel Default configuration doesn't have your module
// name prepended to the Swift class. To enable removing the @objc attribute, change the Class for your entity to `ModuleName.Post`
@objc(Post)
class Post: NSManagedObject, EntryPersistable {

    // The identifier of the corresponding Content Type in Contentful.
    static let contentTypeId = "post"

    // Properties of the `sys` object of Contentful resources.
    @NSManaged var id: String
    @NSManaged var localeCode: String?
    @NSManaged var createdAt: Date?
    @NSManaged var updatedAt: Date?

    // Custom fields on the content type.
    @NSManaged var body: String?
    @NSManaged var comments: NSNumber?
    // NOTE: Unlike date fields in sys properties, this library can't store `Date` for custom fields.
    // Use `String` and map to date after fetching from CoreData
    @NSManaged var customDateField: String?
    @NSManaged var date: Date?
    @NSManaged var slug: String?
    @NSManaged var tags: Data?
    @NSManaged var title: String?
    @NSManaged var authors: NSOrderedSet?
    @NSManaged var category: NSOrderedSet?
    @NSManaged var theFeaturedImage: Asset?

    // Define the mapping from the fields on your Contentful.Entry to your model class.
    // In the below example, only the `title`, `date` and `author` fields and `featuredImage` link will be populated.
    // IMPORTANT: This should not include metadata from the `sys` object (e.g. id, createdAt, etc.)
    static func fieldMapping() -> [FieldName: String] {
        return [
            "title": "title",
            "featuredImage": "theFeaturedImage",
            "author": "authors"
            "date": "date"
        ]
    }
}

class Product: NSManagedObject {
    // Contentful metadata
    @NSManaged var id: String
    @NSManaged var localeCode: String?
    @NSManaged var createdAt: Date?
    @NSManaged var updatedAt: Date?

    // Defined properties in Contentful
    @NSManaged public var name: String?
    @NSManaged public var relatedProducts: NSOrderedSet?
}

extension Product: EntryPersistable {
    public static var contentTypeId = "product"
    public static func fieldMapping() -> [FieldName: String] {
        return [
            "name": "name",
            "relatedProducts": "relatedProducts",
        ]
    }
}

for product in products {
  if let relatedProductsSet = product.relatedProducts,
      let productsArray = relatedProductsSet.array as? [Product]
  {
      // productsArray is now [Product]
      for product in productsArray {
          // Access product properties here, e.g., product.name
          print("Related product:", product.id, product.name)
      }
  } else {
      print("No related products or unable to cast")
  }
}