You love Swift's Codable protocol and use it everywhere, who doesn't!
Here is an easy and very light way to store and retrieve Codable objects to various persistence layers, in a few lines of code!
PersistenceKit offers 3 layers of persistence suitable for most use cases:
- Stores data using
UserDefaults. - Suitable for storing a reasonable number of objects.
- Stores data directly to directories in the app's default documents directory or shared app group directory using
FileManager. - Suitable for storing large number of objects.
- Stores data to OS's keychain using the
Security Framework. - Suitable for storing sensitive data, like access tokens.
v1.3 brings Swift 5.0 support
CocoaPods
To integrate PersistenceKit into your Xcode project using CocoaPods, specify it in your Podfile:
pod 'PersistenceKit'Carthage
To integrate PersistenceKit into your Xcode project using Carthage, specify it in your Cartfile:
github "Teknasyon-Teknoloji/PersistenceKit"
Swift Package Manager
You can use The Swift Package Manager to install PersistenceKit by adding the proper description to your Package.swift file:
import PackageDescription
let package = Package(
name: "YOUR_PROJECT_NAME",
targets: [],
dependencies: [
.package(url: "https://github.com/Teknasyon-Teknoloji/PersistenceKit.git", from: "0.1")
]
)
Note that the Swift Package Manager is still in early design and development, for more information checkout its GitHub Page
Let's say you have 2 structs; User and Laptop defined as bellow:
struct User: Codable {
var id: Int
var firstName: String
var lastName: String
var laptop: Laptop?
}struct Laptop: Codable {
var model: String
var name: String
}The Identifiable protocol lets PersistenceKit knows what is the unique id for each object.
struct User: Codable, Identifiable {
static let idKey = \User.id
...
}struct Laptop: Codable, Identifiable {
static let idKey = \Laptop.model
...
}Notice how
UserusesIntfor its id, whileLaptopusesString, in fact the id can be any type. PersistenceKit uses Swift keypaths to refer to properties without actually invoking them. Swift rocks 🤘
// To save objects to UserDefaults, create UserDefaultsStore:
let usersStore = UserDefaultsStore<User>(uniqueIdentifier: "users")!
let laptopsStore = UserDefaultsStore<Laptop>(uniqueIdentifier: "laptops")!
// To save a single object to UserDefaults, create UserDefaultsStore:
let userStore = SingleUserDefaultsStore<User>(uniqueIdentifier: "user")!
// If you want to share data between app and extentions:
let sharedUsersStore = UserDefaultsStore<User>(uniqueIdentifier: "users", groupIdentifier: "com.yourCompany.app")!
let sharedUserStore = SingleUserDefaultsStore<User>(uniqueIdentifier: "user", groupIdentifier: "com.yourCompany.app")!
// To save objects to the file system, create FilesStore:
let usersStore = FilesStore<User>(uniqueIdentifier: "users")
let laptopsStore = FilesStore<Laptop>(uniqueIdentifier: "laptops")
// To save objects to the app group shared file system, create FilesStore:
let appGroup = Bundle.main.infoDictionary?["appGroup"] as? String ?? "group.company.app"
let usersStore = FilesStore<User>(uniqueIdentifier: "users", groupIdentifier: appGroup)
let laptopsStore = FilesStore<Laptop>(uniqueIdentifier: "laptops", groupIdentifier: appGroup)
// To save a single object to the file system, create SingleFilesStore:
let userStore = SingleFilesStore<User>(uniqueIdentifier: "user")
// To save a single object to the app group shared file system, create SingleFilesStore:
let appGroup = Bundle.main.infoDictionary?["appGroup"] as? String ?? "group.company.app"
let userStore = SingleFilesStore<User>(uniqueIdentifier: "user", groupIdentifier: appGroup)
// To save a single object to the system's keychain, create SingleKeychainStore:
let userStore = SingleKeychainStore<User>(uniqueIdentifier: "user")let macbook = Laptop(model: "A1278", name: "MacBook Pro")
let john = User(userId: 1, firstName: "John", lastName: "Appleseed", laptop: macbook)
// Save an object to a store
try! usersStore.save(john)
// Save an array of objects to a store
try! usersStore.save([jane, steve, jessica])
// Get an object from store
let user = store.object(withId: 1)
let laptop = store.object(withId: "A1278")
// Get all objects in a store
let laptops = laptopsStore.allObjects()
// Check if store has an object
print(usersStore.hasObject(withId: 10)) // false
// Iterate over all objects in a store
laptopsStore.forEach { laptop in
print(laptop.name)
}
// Delete an object from a store
usersStore.delete(withId: 1)
// Delete all objects in a store
laptops.deleteAll()
// Know how many objects are stored in a store
let usersCount = usersStore.objectsCount- iOS 8.0+ / macOS 10.10+ / tvOS 9.0+ / watchOS 2.0+
- Xcode 10.0+
- Swift 4.2+
Special thanks to:
- Paul Hudson for his article on how to use Swift keypaths to write more natural code.
- Icon made by freepik from flaticon.com.
PersistenceKit is released under the MIT license. See LICENSE for more information.