Decide methods for the Swift SDK

Use the Decide methods to return flag decisions for a user. The flag decision includes flag enabled/disabled status and flag variation.

This page describes the following Decide methods:

• Decide
• Decide All
• Decide for specified keys

Decide

Version

SDK 3.7 and higher

Description

Returns a decision result for a flag key for a user. The decision result is returned in an OptimizelyDecision object and contains all data required to deliver the flag rule.

Decide is a method of the UserContext object. See OptimizelyUserContext for details.

See the OptimizelyDecision for details of the returned decision object.

Parameters

The following table describes parameters for the Decide method:

OptimizelyDecideOption

The following example shows how you can set options individually on any Decide method, or as global defaults when you instantiate the Optimizely client. See Initialize SDK.

# set global default decide options when initializing the client
let optimizely = OptimizelyClient(sdkKey: sdkKey, defaultDecideOptions: [.disableDecisionEvent])


# set additional options in a decide call
let user = optimizely.createUserContext(userId: "user123")
let decisions = user.decideAll(options: [.enabledFlagsOnly, .disableDecisionEvent])

The following table shows details for the OptimizelyDecideOption.

Returns

The Decide method returns an OptimizelyDecision object. For more information, see OptimizelyDecision.

If the method encounters a critical error (SDK not ready, invalid flag key, etc), then it returns a decision with a null Variation Key field and populates the Reasons field with error messages (regardless of the Include Reasons option).

Example decision

The following is an example of calling the Decide method and accessing the returned OptimizelyDecision object:

// create the user and decide which flag rule & variation they bucket into 
let user = optimizelyClient.createUserContext(userId: "user123", attributes: ["logged_in": true])
let decision = user.decide(key: "product_sort")

// Did the decision fail with a critical error?
guard let variationKey = decision.variationKey else {
  print("[decide] error: \(decision.reasons)")
	return
}

// flag enabled state:
let enabled: Bool = decision.enabled

// String variable value:
let value1: String? = decision.variables.getValue(jsonPath: "sort_method")
// or:
let value2: String? = decision.variables.toMap()["sort_method"] as? String

// all variable values
let allVarValues: OptimizelyJSON = decision.variables

// variation. if null, decision fail with a critical error
let variationKey: String = decision.variationKey

// flag decision reasons
let reasons: [String] = decision.reasons

// user for which the decision was made
let userContext: OptimizelyUserContext = decision.userContext

Side effects

Invokes the DECISION notification listener if this listener is enabled.

Decide All

Returns decisions for all active (unarchived) flags for a user.

See OptimizelyDecision for details.

Version

SDK v3.6 and higher

Description

Use the Decide All method to return a map of flag decisions for a user.

Parameters

The following table describes parameters for the Decide All method:

Returns

The Decide All method returns a map of OptimizelyDecisions. For more information, see OptimizelyDecision.

If the method fails for all flags (for example, the SDK isn't ready or the user context is invalid), then it returns an empty map. If the method detects an error for a specific flag, it returns error messages in the Reasons field of the decision for that flag.

Examples

The following is an example of getting flags for the user with the Decide All call:

// make decisions for all active (unarchived) flags in the project for a user
let decisions = user.decideAll()
// or only for enabled flags
let decisions = user.decideAll(options: [.enabledFlagsOnly])

let flagKeys = decisions.keys
let flagDecisions = decisions.values
let decisionForFlag1 = decisions["flag_1"]

Side effects

Invokes the DECISION notification listener for each decision if this listener is enabled.

Decide for specified keys

In the Swift SDK, the Decide method returns a map of flag decisions for specific flag keys if you pass a keys parameter.

Version

SDK v3.6 and higher

Description

Get a map of flag decisions for specific flag keys. Note that in SDKs where the Decide method is not polymorphic and therefore cannot accept a keys parameter, there is instead a Decide For Keys method for the functionality described in this section.

Parameters

The following table describes parameters for the Decide method:

Returns

Returns a map of OptimizelyDecisions. For more information, see OptimizelyDecision.

If the method fails for all flags (for example, the SDK isn't ready or the user context is invalid), then it returns an empty map. If the method detects an error for a specific flag, it returns error messages in the Reasons field of the decision for that flag.

Example

The following is an example of getting specified flags for the user:

// make a decisions for specific enabled  flags
let decisions = user.decide(keys: ["flag_1", "flag_2"], options: [.enabledOnly])

let decisionForFlag1 = decisions["flag_1"]
let decisionForFlag2 = decisions["flag_2"]

Side effects

Invokes the DECISION notification listener for each decision if this listener is enabled.

Source files

The language and platform source files containing the implementation for Swift are available on GitHub.