A/B Smartly SDK

A/B Smartly - Swift SDK

Compatibility

The A/B Smartly Swift SDK is supported on macOS version 10.10 or later and iOS version 10 or later.

Installation

Swift Package Manager

To install the A/B Smartly SDK using Swift Package Manager, following these steps:

• In Xcode go to: File -> Swift Packages -> Add Package Dependency...

• Enter the A/B Smartly Swift SDK GitHub repository: https://github.com/absmartly/swift-sdk

• Select the SDK version (latest recommended)

• Select the ABSmartly library

Cocoapods

To install the A/B Smartly SDK with CocoaPods, add the following lines to your Podfile:

pod 'ABSmartlySwiftSDK', '~> 1.0.2'

Run the following command to update your Xcode project:

pod install

Getting Started

Please follow the installation instructions before trying the following code:

Initialization

Import the SDK into your application:

import ABSmartly

Initialize the client and the SDK

let sdk: ABSmartlySDK
do {
    let clientConfig = ClientConfig(
        apiKey: ProcessInfo.processInfo.environment["ABSMARTLY_API_KEY"] ?? "",
        application: ProcessInfo.processInfo.environment["ABSMARTLY_APPLICATION"] ?? "",
        endpoint: ProcessInfo.processInfo.environment["ABSMARTLY_ENDPOINT"] ?? "",
        environment: ProcessInfo.processInfo.environment["ABSMARTLY_ENVIRONMENT"] ?? ""))

    let client = try DefaultClient(config: clientConfig)
    let sdkConfig = ABSmartlyConfig(client: client)
    sdk = try ABSmartlySDK(config: sdkConfig)
} catch {
    print(error.localizedDescription)
    return
}

Creating a new Context

let contextConfig: ContextConfig = ContextConfig()
contextConfig.setUnit(unitType: "device_id", uid: UIDevice.current.identifierForVendor!.uuidString))

let context = sdk.createContext(config: contextConfig)
context.waitUntilReady().done { context in
    print("context ready")
}

Creating a new Context with pre-fetched data

When doing full-stack experimentation with A/B Smartly, we recommend creating a context only once on the server-side. Creating a context involves a round-trip to the A/B Smartly event collector. We can avoid repeating the round-trip on the client-side by sending the server-side data embedded with other application data. Then we can initialize the A/B Smartly context directly with it.

let contextConfig: ContextConfig = ContextConfig()
contextConfig.setUnit(unitType: "device_id", uid: UIDevice.current.identifierForVendor!.uuidString)

let context = sdk.createContextWithData(config: anotherContextConfig, contextData: contextData)

Setting extra units for a context

You can add additional units to a context by calling the setUnit() or the setUnits() method. This method may be used for example, when a user logs in to your application, and you want to use the new unit type to the context. Please note that you cannot override an already set unit type as that would be a change of identity, and will crash your application. In this case, you must create a new context instead. The setUnit() and setUnits() methods can be called before the context is ready.

context.setUnit(unitType: "db_user_id", uid: "1000013");
context.setUnits([
    "db_user_id": "1000013"
]);

Setting context attributes

The setAttribute() and setAttributes() methods can be called before the context is ready.

context.setAttribute(name: "device", value: UIDevice.current.model)
context.setAttributes(["customer_age": "new_customer", "screen": "product"])

Selecting a treatment

let treatment = context.getTreatment("exp_test_experiment")
if treatment == 0 {
    // user is in control group (variant 0)
} else {
    // user is in treatment group
}

Selecting a treatment variable

let variable = context.getVariableValue("my_variable", defaultValue: 10)

Tracking a goal achievement

Goals are created in the A/B Smartly web console.

context.track("payment", properties: ["item_count": 1, "total_amount": 1999.99])

Publishing pending data

Sometimes it is necessary to ensure all events have been published to the A/B Smartly collector, before proceeding. You can explicitly call the publish() method.

context.publish().done {
    print("all pending events published")
}

Finalizing

The close() methods will ensure all events have been published to the A/B Smartly collector, like publish(), and will also "seal" the context, throwing an error if any method that could generate an event is called.

context.close().done {
    print("context closed")
}

Refreshing the context with fresh experiment data

For long-running contexts, the context is usually created once when the application is first reached. However, any experiments being tracked in your production code, but started after the context was created, will not be triggered. To mitigate this, we can use the setRefreshInterval() method on the context config.

let contextConfig: ContextConfig = ContextConfig()
contextConfig.setUnit(unitType: "device_id", uid: UIDevice.current.identifierForVendor!.uuidString)
contextConfig.refreshInterval = 4 * 3600; // every 4 hours

Alternatively, the refresh() method can be called manually.

context.refresh().done {
    print("refreshed")
}

Using a custom Event Logger

The A/B Smartly SDK can be instantiated with an event logger used for all contexts. In addition, an event logger can be specified when creating a particular context, in the ContextConfig.

// example implementation
public class CustomEventLogger : ContextEventLogger {
    public func handleEvent(context: Context, event: ContextEventLoggerEvent) {
        switch event {
        case let .exposure(exposure):
            print("exposed to experiment: \(exposure.name)")
        case let .goal(goal):
            print("goal tracked: \(goal.name)")
        case let .error(error):
            print("error: ", error.localizedDescription)
        case let .publish(event):
            break
        case let .ready(data):
            break
        case let .refresh(data):
            break
        case .close:
            break
        }
    }
}

// for all contexts, during sdk initialization
let absmartlyConfig = ABSmartlyConfig(
        contextDataProvider: nil,
        contextEventHandler: nil,
        contextEventLogger: CustomEventLogger(),
        variableParser: nil,
        scheduler: nil,
        client: client)

// OR, alternatively, during a particular context initialization
let contextConfig = ContextConfig()
contextConfig.eventLogger = CustomEventLogger()

The event data depends on the type of event. Currently, the SDK logs the following events:

event	when	data
error	Context receives an error	Error object
ready	Context turns ready	ContextData used to initialize the context
refresh	Context.refresh() method succeeds	ContextData used to refresh the context
publish	Context.publish() method succeeds	PublishEvent sent to the A/B Smartly event collector
exposure	Context.getTreatment() method succeeds on first exposure	Exposure enqueued for publishing
goal	Context.track() method succeeds	GoalAchievement enqueued for publishing
close	Context.close() method succeeds the first time	nil

Peek at treatment variants

Although generally not recommended, it is sometimes necessary to peek at a treatment or variable without triggering an exposure. The A/B Smartly SDK provides a peekTreatment() method for that.

let treatment = context.peekTreatment(experimentName: "exp_test_experiment")

if treatment == 0 {
    // user is in control group (variant 0)
} else {
    // user is in treatment group
}

Peeking at variables

let color = context.peekVariableValue("colorGComponent", defaultValue: 255)

Overriding treatment variants

During development, for example, it is useful to force a treatment for an experiment. This can be achieved with the override() and/or overrides() methods. The setOverride() and setOverrides() methods can be called before the context is ready.

context.setOverride(experimentName: "exp_test_experiment", variant: 1)  // force variant 1 of treatment
context.setOverrides(["exp_test_experiment": 1, "exp_another_experiment": 0])

About A/B Smartly

A/B Smartly is the leading provider of state-of-the-art, on-premises, full-stack experimentation platforms for engineering and product teams that want to confidently deploy features as fast as they can develop them. A/B Smartly's real-time analytics helps engineering and product teams ensure that new features will improve the customer experience without breaking or degrading performance and/or business metrics.

Have a look at our growing list of clients and SDKs:

• Java SDK
• JavaScript SDK
• PHP SDK
• Swift SDK
• Vue2 SDK