chore: perform token exchange when needed during setup

Author: johannesliespace

PACECloudSDK/IDKit/IDKit.swift

@@ -45,12 +45,20 @@ public class IDKit {
 
         guard let session = SessionCache.loadSession(for: PACECloudSDK.shared.environment) else { return }
         self.session = session
-
-        handleUpdatedAccessToken(with: session.lastTokenResponse?.accessToken, exchangeToken: nil)
     }
 
     private static func setup(with configuration: OIDConfiguration, userAgentType: UserAgentType) {
         sharedInstance = IDKit(with: configuration, userAgentType: userAgentType)
+        sharedInstance?.setInitialToken()
+    }
+    
+    func setInitialToken() {
+        let token = self.session?.lastTokenResponse?.accessToken ?? ""
+        var exchangeToken: String?
+        if let tokenExhangeConfig = configuration.tokenExchangeConfig {
+            exchangeToken = SessionCache.loadExchangeToken(for: PACECloudSDK.shared.environment)
+        }
+        handleUpdatedAccessToken(with: token, exchangeToken: exchangeToken)
     }
 
     static func determineOIDConfiguration(with customOIDConfig: OIDConfiguration?, userAgentType: UserAgentType) {

PACECloudSDK/IDKit/Session/IDKit+TokenHandling.swift

@@ -159,6 +159,7 @@ extension IDKit {
             var returnToken: String?
             if let data = data, let jsonString = data.prettyPrintedJSONString, let exchangeToken = jsonString["access_token"] as? String {
                 returnToken = exchangeToken
+                SessionCache.persistExchangeToken(exchangeToken, for: PACECloudSDK.shared.environment)
                 IDKitLogger.i("[TokenExchange] Token exchange successful")
             } else {
                 IDKitLogger.e("[TokenExchange] Error while token exchange \(String(describing: error))")
@@ -237,7 +238,6 @@ extension IDKit {
                         }
                         self.handleUpdatedAccessToken(with: accessToken, exchangeToken: newApiToken)
                         IDKitLogger.i("[TokenRefresh] Refresh successful")
-
                         // Update persisted session
                         SessionCache.persistSession(session, for: PACECloudSDK.shared.environment)
                         return

PACECloudSDK/IDKit/Utils/IDKitConstants.swift

@@ -12,5 +12,6 @@ struct IDKitConstants {
 
     struct UserDefaults {
         static let sessionCache = "sessionCache"
+        static let exchangeTokenCache = "exchangeTokenCache"
     }
 }

PACECloudSDK/IDKit/Utils/SessionCache.swift

@@ -50,8 +50,27 @@ class SessionCache {
             SDKUserDefaults.set(nil, for: $0, isUserSensitiveData: false)
         }
     }
-
+    
     private static func sessionCacheKey(for environment: PACECloudSDK.Environment) -> String {
         "\(IDKitConstants.UserDefaults.sessionCache)_\(environment.rawValue)"
     }
 }
+
+extension SessionCache {
+    static func loadExchangeToken(for environment: PACECloudSDK.Environment) -> String? {
+        IDKitLogger.d("Attempting to load previous exchange token...")
+
+        let token = SDKUserDefaults.string(for: exchangeTokenCacheKey(for: environment), isUserSensitiveData: false)
+        return token
+    }
+    
+    static func persistExchangeToken(_ token: String, for environment: PACECloudSDK.Environment) {
+        IDKitLogger.d("Persisting exchange token")
+
+        SDKUserDefaults.set(token, for: exchangeTokenCacheKey(for: environment), isUserSensitiveData: false)
+    }
+    
+    private static func exchangeTokenCacheKey(for environment: PACECloudSDK.Environment) -> String {
+        "\(IDKitConstants.UserDefaults.exchangeTokenCache)_\(environment.rawValue)"
+    }
+}