refact(getValue): Simplifying getValue by default nil value for jsonPath. (#339)

Author: yasirfolio3

Sources/Optimizely/OptimizelyJSON.swift

@@ -71,13 +71,31 @@ public class OptimizelyJSON: NSObject {
     ///
     /// If JSON Data is {"k1":true, "k2":{"k3":"v3"}}
     ///
-    /// Set jsonPath to "k2" to access {"k3":"v3"} or set it to "k2.k3" to access "v3"
-    /// Set it to nil or empty to access the entire JSON data.
+    /// Set jsonPath to "k2" to access {"k3":"v3"} or set it to "k2.k3" to access "v3".
+    /// Set it to nil or empty to access the entire JSON data. See more examples below:
+    ///
+    ///
+    ///     struct Student: Decodable {
+    ///         let name: String
+    ///         let age: Int
+    ///         let address: Address
+    ///     }
+    ///
+    ///     struct Address: Decodable {
+    ///         let state: String
+    ///         let emails: [String]
+    ///     }
+    ///
+    ///     let student: Student? = optimizelyJSON.getValue(jsonPath: nil)
+    ///     let address: Address? = optimizelyJSON.getValue(jsonPath: "address")
+    ///     let name: String? = optimizelyJSON.getValue(jsonPath: "name")
+    ///     let emails: [String]? = optimizelyJSON.getValue(jsonPath: "address.emails")
+    ///
     ///
     /// - Parameters:
     ///   - jsonPath: Key path for the value.
     /// - Returns: Value if decoded successfully
-    public func getValue<T: Decodable>(jsonPath: String? = nil) -> T? {
+    public func getValue<T: Decodable>(jsonPath: String?) -> T? {
         func handler(value: Any) -> T? {
             guard JSONSerialization.isValidJSONObject(value) else {
                 // Try and typecast value to required return type
@@ -102,8 +120,26 @@ public class OptimizelyJSON: NSObject {
     ///
     /// If JSON Data is {"k1":true, "k2":{"k3":"v3"}}
     ///
-    /// Set jsonPath to "k2" to access {"k3":"v3"} or set it to "k2.k3" to access "v3"
-    /// Set it to nil or empty to access the entire JSON data.
+    /// Set jsonPath to "k2" to access {"k3":"v3"} or set it to "k2.k3" to access "v3".
+    /// Set it to nil or empty to access the entire JSON data. See more examples below:
+    ///
+    ///
+    ///     struct Student: Decodable {
+    ///         let name: String
+    ///         let age: Int
+    ///         let address: Address
+    ///     }
+    ///
+    ///     struct Address: Decodable {
+    ///         let state: String
+    ///         let emails: [String]
+    ///     }
+    ///
+    ///     let student: Student? = optimizelyJSON.getValue(jsonPath: nil)
+    ///     let address: Address? = optimizelyJSON.getValue(jsonPath: "address")
+    ///     let name: String? = optimizelyJSON.getValue(jsonPath: "name")
+    ///     let emails: [String]? = optimizelyJSON.getValue(jsonPath: "address.emails")
+    ///
     ///
     /// - Parameters:
     ///   - jsonPath: Key path for the value.

Tests/OptimizelyTests-APIs/OptimizelyClientTests_OptimizelyJSON.swift

@@ -280,7 +280,7 @@ extension OptimizelyClientTests_OptimizelyJSON {
     }
 
     func testGetValueForNilJSONKeyAndInvalidType() {
-        let value: Int? = self.optimizelyJSON.getValue()
+        let value: Int? = self.optimizelyJSON.getValue(jsonPath: nil)
         XCTAssertNil(value)
     }
 
@@ -290,7 +290,7 @@ extension OptimizelyClientTests_OptimizelyJSON {
     }
 
     func testGetValueForNilJSONKeyAndEmptyDecodableStruct() {
-        let value: EmptyDecodableStruct? = self.optimizelyJSON.getValue()
+        let value: EmptyDecodableStruct? = self.optimizelyJSON.getValue(jsonPath: nil)
         XCTAssertNotNil(value)
     }
 
@@ -314,7 +314,7 @@ extension OptimizelyClientTests_OptimizelyJSON {
     }
 
     func testGetValueForNilJsonKeyAndValidDecodableStruct() {
-        let value: ValidDecodableStruct? = self.optimizelyJSON.getValue()
+        let value: ValidDecodableStruct? = self.optimizelyJSON.getValue(jsonPath: nil)
         XCTAssertNotNil(value)
 
         let expectedStruct = ValidDecodableStruct(