Sticky Bucketing

Optionally add a storage layer when instantiating tesfy by conforming to the protocol TesfyStorable. This layer could be whatever you want (UserDefaults, Keychain, Core Data, SQLite, etc.). This way even allocation or attributes changes in users will stick with the same variation.

class TesfyStorage: TesfyStorable {
    var storage: [String: String]
    init(storage: [String: String]? = [:]) {
        self.storage = storage ?? [:]
    }
    func get(id: String) -> String? {
        return storage[id]
    }
    func store(id: String, value: String?) {
        self.storage[id] = value
    }
}
let tesfyStorage = TesfyStorage()
let tesfy = Tesfy(datafile: datafile, storage: tesfyStorage)
let userId = "676380e0-7793-44d6-9189-eb5868e17a86"
let experimentId = "experiment-2"
tesfy.getVariationId(experimentId: experimentId, userId: userId, attributes: "{ \"countryCode\": \"us\" }") // "0"
tesfy.getVariationId(experimentId: experimentId, userId: userId, attributes: "{ \"countryCode\": \"ve\" }") // "0"