Summary

Stores framework provides a unified API for storing, retrieving and observing Key-Value pairs on iOS and Android.

Rationale

Deciding where to store data, how to transform it, how to observe it, or where to save the key requires additional decision making and manual work. This framework alleviates all that by providing a simple consistent API across both platforms.

Usage

First we need to define a StoreKey. A StoreKey defines how, what and where to store the value.

On iOS:

// Add an extension on StoreKeys
extensionStoreKeys{
// This will store a String in UserDefaults
staticletuserId=UserDefaultsStoreKey<String>("userId")
// This will cache a Boolean in memory.
staticletisPillHidden=MemoryStoreKey<Bool>("isPillHidden")
// This will securily store a User object in Keychain
staticletuser=KeychainStoreKey<User>("user")}

On Android

// Add an extension on StoreKeys object// This will store a String in Android SharedPreferencesvalStoreKeys.userId by lazy { SharedPrefsStoreKey(id ="userId", clazz =String::class.java) }
// This will cache a Boolean in memory.valStoreKeys.isPillHidden by lazy { MemoryStoreKey(id ="isPillHidden", clazz =Boolean::class.java) }
// This will encrypt & store a User object in SharedPreferencesvalStoreKeys.user by lazy { EncryptedSharedPrefsStoreKey(id ="user", clazz =User::class.java) }

Once the key is defined, the store can be accessed, modified, or observed as follows:

On iOS

// Get operation
letuserId= store.get(.userId)letuser= store.get(.user)
// Set operation
store.set(.userId,"420")
store.set(.user,User(id:123, name:"Adam"))
// Observe operation
store.observe(.isPillHidden).subscribe(onNext:{ value in
// value is of type Bool
})

On Android:

// Get operationval userId = store.get(StoreKeys.userId)
val user = store.get(StoreKeys.user)
// Set operation
store.set(StoreKeys.userId, "420")
store.set(StoreKeys.user, User(id =123, name ="Adam"))
// Observe operation
store.observe(StoreKeys.isPillHidden)
.subscribe { value ->// value is of type Boolean
}