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This topic describes the OptimizelyJSON object which the Optimizely Swift SDK uses.

Since statically typed languages lack native support for JSON, the Swift SDK uses the OptimizelyJSON object to retrieve JSON in a flexible way. The Get All Feature Variables and Get Feature Variable JSON methods use OptimizelyJSON to return feature variables. For more information, see Get All Feature Variables and Get Feature Variable.


SDK v3.4.0 and higher


You can access JSON representations with the following methods:

toStringnoneReturns a string representation of the JSON object
toMapnoneReturns a map representation of the JSON object: [String: Any]
getValueString jsonPathReturns a specified schema object (T) with the key/value pair of the JSON key you pass to this method.

If JSON key is null or empty, it populates your schema object with all JSON key/value pairs.

You can retrieve information for a nested member of the JSON data structure by using flattened JSON dot notation.
For example, if you want to access the key nestedField2 in {field1: {nestedField2: "blah"}}, you can call getValue with the parameter "field1.nestedField2".

The OptimizelyJSON object is defined as follows:

public class OptimizelyJSON: NSObject {
    public func toString() -> String?
    public func toMap() -> [String: Any]
    public func getValue<T: Decodable>(jsonPath: String? = nil) -> T?
  	public func getValue<T>(jsonPath: String?) -> T?


You can easily use OptimizelyJSON object, for example to:

  • Get a JSON string by calling the toString method, or
  • Retrieve a specified schema from the OptimizelyJSON object by calling the getValue method.

The following example shows how to use an OptimizelyJSON object to populate a schema object you declare.

//declare a schema object into which you want to unmarshal OptimizelyJson content:
struct SSub: Decodable {
    var field: String = ""
struct SObj: Decodable {
    var field1: Int = 0
    var field2: Double = 0.0
    var field3: String = ""
    var field4: SSub = SSub()
//parse all json key/value pairs into your schema, sObj
let robj: SObj? = self.optimizelyJSON.getValue()
//or, parse the specified key/value pair with an integer value
let rint: Int? = self.optimizelyJSON.getValue(jsonPath: "field1")
//or, parse the specified key/value pair with a string value
let strValue: String? = self.optimizelyJSON.getValue(jsonPath: "field4.field")