Session lifecycle updates (#83)

src/internal/http/DescopeClient.swift

@@ -437,10 +437,10 @@ final class DescopeClient: HTTPClient, @unchecked Sendable {
                 user?.setCustomAttributes(from: dict)
             }
             if sessionJwt == nil || sessionJwt == "" {
-                sessionJwt = try findTokenCookie(named: sessionCookieName, in: cookies)
+                sessionJwt = findTokenCookie(named: sessionCookieName, in: cookies)
             }
             if refreshJwt == nil || refreshJwt == "" {
-                refreshJwt = try findTokenCookie(named: refreshCookieName, in: cookies)
+                refreshJwt = findTokenCookie(named: refreshCookieName, in: cookies)
             }
         }
     }
@@ -579,10 +579,10 @@ private extension DeliveryMethod {
     }
 }
 
-private func findTokenCookie(named name: String, in cookies: [HTTPCookie]) throws(DescopeError) -> String {
+private func findTokenCookie(named name: String, in cookies: [HTTPCookie]) -> String? {
     // keep only cookies matching the required name
     let cookies = cookies.filter { name.caseInsensitiveCompare($0.name) == .orderedSame }
-    guard !cookies.isEmpty else { throw DescopeError.decodeError.with(message: "Missing value for \(name) cookie") }
+    guard !cookies.isEmpty else { return nil }
 
     // try to make a deterministic choice between cookies by looking for the best matching token
     let tokens = cookies.compactMap { try? Token(jwt: $0.value) }.sorted { a, b in
@@ -591,7 +591,7 @@ private func findTokenCookie(named name: String, in cookies: [HTTPCookie]) throw
     }
 
     // try to find the best match by prioritizing the newest non-expired token
-    guard let token = tokens.first else { throw DescopeError.decodeError.with(message: "Invalid value for \(name) cookie") }
+    guard let token = tokens.first else { return nil }
 
     return token.jwt
 }

src/sdk/Config.swift

@@ -32,7 +32,7 @@ public struct DescopeConfig {
     /// This property can be useful to test code that uses the Descope SDK without any
     /// network requests actually taking place. In most other cases there shouldn't be
     /// any need to use it.
-    public var networkClient: DescopeNetworkClient? = nil
+    public var networkClient: DescopeNetworkClient?
 }
 
 /// The ``DescopeLogger`` class can be used to customize logging functionality in the Descope SDK.

src/sdk/SDK.swift

@@ -81,7 +81,7 @@ public class DescopeSDK {
     /// override the ``DescopeSDK`` object's default networking client with one that always
     /// fails, using code such as this (see ``DescopeNetworkClient``):
     ///
-    ///     let descope = DescopeSDK(projectId: "") { config in
+    ///     let descope = DescopeSDK(projectId: "test") { config in
     ///         config.networkClient = FailingNetworkClient()
     ///     }
     ///     testOTPNetworkError(descope)
@@ -143,15 +143,15 @@ public extension DescopeSDK {
     static let name = "DescopeKit"
 
     /// The Descope SDK version
-    static let version = "0.9.10"
+    static let version = "0.9.11"
 }
 
 // Internal
 
 private extension DescopeSessionManager {
     convenience init(sdk: DescopeSDK) {
         let storage = SessionStorage(projectId: sdk.config.projectId)
-        let lifecycle = SessionLifecycle(auth: sdk.auth)
+        let lifecycle = SessionLifecycle(auth: sdk.auth, storage: storage, logger: sdk.config.logger)
         self.init(storage: storage, lifecycle: lifecycle)
     }
 }

src/session/Lifecycle.swift

@@ -20,32 +20,49 @@ public protocol DescopeSessionLifecycle: AnyObject {
 /// or if it's already expired.
 public class SessionLifecycle: DescopeSessionLifecycle {
     public let auth: DescopeAuth
+    public let storage: DescopeSessionStorage
+    public let logger: DescopeLogger?
 
-    public init(auth: DescopeAuth) {
+    public init(auth: DescopeAuth, storage: DescopeSessionStorage, logger: DescopeLogger?) {
         self.auth = auth
+        self.storage = storage
+        self.logger = logger
     }
 
     public var stalenessAllowedInterval: TimeInterval = 60 /* seconds */
 
-    public var stalenessCheckFrequency: TimeInterval = 30 /* seconds */ {
+    public var periodicCheckFrequency: TimeInterval = 30 /* seconds */ {
         didSet {
-            if stalenessCheckFrequency != oldValue {
+            if periodicCheckFrequency != oldValue {
                 resetTimer()
             }
         }
     }
 
+    public var shouldSaveAfterPeriodicRefresh: Bool = true
+
     public var session: DescopeSession? {
         didSet {
             if session?.refreshJwt != oldValue?.refreshJwt {
                 resetTimer()
             }
+            if let session, session.refreshToken.isExpired {
+                logger(.debug, "Session has an expired refresh token", session.refreshToken.expiresAt)
+            }
         }
     }
 
     public func refreshSessionIfNeeded() async throws -> Bool {
         guard let current = session, shouldRefresh(current) else { return false }
+
+        logger(.info, "Refreshing session that is about to expire", current.sessionToken.expiresAt.timeIntervalSinceNow)
         let response = try await auth.refreshSession(refreshJwt: current.refreshJwt)
+
+        guard session?.sessionJwt == current.sessionJwt else {
+            logger(.info, "Skipping refresh because session has changed in the meantime")
+            return false
+        }
+
         session?.updateTokens(with: response)
         return true
     }
@@ -61,7 +78,7 @@ public class SessionLifecycle: DescopeSessionLifecycle {
     private var timer: Timer?
 
     private func resetTimer() {
-        if stalenessCheckFrequency > 0, let refreshToken = session?.refreshToken, !refreshToken.isExpired {
+        if periodicCheckFrequency > 0, let refreshToken = session?.refreshToken, !refreshToken.isExpired {
             startTimer()
         } else {
             stopTimer()
@@ -70,9 +87,9 @@ public class SessionLifecycle: DescopeSessionLifecycle {
 
     private func startTimer() {
         timer?.invalidate()
-        timer = Timer.scheduledTimer(withTimeInterval: stalenessCheckFrequency, repeats: true) { [weak self] timer in
+        timer = Timer.scheduledTimer(withTimeInterval: periodicCheckFrequency, repeats: true) { [weak self] timer in
             guard let lifecycle = self else { return timer.invalidate() }
-            Task { @MainActor in
+            Task {
                 await lifecycle.periodicRefresh()
             }
         }
@@ -84,11 +101,22 @@ public class SessionLifecycle: DescopeSessionLifecycle {
     }
 
     private func periodicRefresh() async {
+        if let refreshToken = session?.refreshToken, refreshToken.isExpired {
+            logger(.debug, "Stopping periodic refresh for session with expired refresh token")
+            stopTimer()
+            return
+        }
+
         do {
-            _ = try await refreshSessionIfNeeded()
+            let refreshed = try await refreshSessionIfNeeded()
+            if refreshed, shouldSaveAfterPeriodicRefresh, let session {
+                logger(.debug, "Saving refresh session after periodic refresh")
+                storage.saveSession(session)
+            }
         } catch DescopeError.networkError {
-            // allow retries on network errors
+            logger(.debug, "Ignoring network error in periodic refresh")
         } catch {
+            logger(.error, "Stopping periodic refresh after failure", error)
             stopTimer()
         }
     }

src/session/Manager.swift

@@ -102,7 +102,7 @@ public class DescopeSessionManager {
     ///     each other's saved sessions.
     public func manageSession(_ session: DescopeSession) {
         lifecycle.session = session
-        storage.saveSession(session)
+        saveSession()
     }
 
     /// Clears any active ``DescopeSession`` from this manager and removes it
@@ -122,6 +122,17 @@ public class DescopeSessionManager {
         storage.removeSession()
     }
 
+    /// Saves the active ``DescopeSession`` to the storage.
+    ///
+    /// - Important: There is usually no need to call this method directly.
+    ///     The session is automatically saved when it's refreshed or updated,
+    ///     unless you're using a session manager with custom `stroage` and
+    ///     `lifecycle` objects.
+    public func saveSession() {
+        guard let session else { return }
+        storage.saveSession(session)
+    }
+
     /// Ensures that the session is valid and refreshes it if needed.
     ///
     /// The session manager checks whether there's an active ``DescopeSession`` and if
@@ -170,12 +181,4 @@ public class DescopeSessionManager {
         lifecycle.session?.updateUser(with: user)
         saveSession()
     }
-
-    // Internal
-
-    /// Saves the latest session value to the storage.
-    private func saveSession() {
-        guard let session else { return }
-        storage.saveSession(session)
-    }
 }

src/session/Storage.swift

@@ -35,31 +35,31 @@ public class SessionStorage: DescopeSessionStorage {
     public let projectId: String
     public let store: Store
 
-    private var lastValue: Value?
+    private var lastSaved: EncodedSession?
 
     public init(projectId: String, store: Store = .keychain) {
         self.projectId = projectId
         self.store = store
     }
 
     public func saveSession(_ session: DescopeSession) {
-        let value = Value(sessionJwt: session.sessionJwt, refreshJwt: session.refreshJwt, user: session.user)
-        guard value != lastValue else { return }
-        guard let data = try? JSONEncoder().encode(value) else { return }
+        let encoded = EncodedSession(sessionJwt: session.sessionJwt, refreshJwt: session.refreshJwt, user: session.user)
+        guard lastSaved != encoded else { return }
+        guard let data = try? JSONEncoder().encode(encoded) else { return }
         try? store.saveItem(key: projectId, data: data)
-        lastValue = value
+        lastSaved = encoded
     }
 
     public func loadSession() -> DescopeSession? {
         guard let data = try? store.loadItem(key: projectId) else { return nil }
-        guard let value = try? JSONDecoder().decode(Value.self, from: data) else { return nil }
-        let session = try? DescopeSession(sessionJwt: value.sessionJwt, refreshJwt: value.refreshJwt, user: value.user)
-        lastValue = value
+        guard let encoded = try? JSONDecoder().decode(EncodedSession.self, from: data) else { return nil }
+        let session = try? DescopeSession(sessionJwt: encoded.sessionJwt, refreshJwt: encoded.refreshJwt, user: encoded.user)
+        lastSaved = encoded
         return session
     }
 
     public func removeSession() {
-        lastValue = nil
+        lastSaved = nil
         try? store.removeItem(key: projectId)
     }
 
@@ -80,23 +80,35 @@ public class SessionStorage: DescopeSessionStorage {
     }
 
     /// A helper struct for serializing the ``DescopeSession`` data.
-    private struct Value: Codable, Equatable {
+    private struct EncodedSession: Codable, Equatable {
         var sessionJwt: String
         var refreshJwt: String
         var user: DescopeUser
     }
 }
 
-public extension SessionStorage.Store {
+extension SessionStorage.Store {
     /// A store that does nothing.
-    static let none = SessionStorage.Store()
-    
+    public static let none = SessionStorage.Store()
+
     /// A store that saves the session data to the keychain.
-    static let keychain = SessionStorage.KeychainStore()
+    public static let keychain = SessionStorage.KeychainStore()
 }
 
-public extension SessionStorage {
-    class KeychainStore: Store {
+extension SessionStorage {
+    public class KeychainStore: Store {
+        #if os(iOS)
+        private let accessibility: String
+
+        public override init() {
+            self.accessibility = kSecAttrAccessibleAfterFirstUnlock as String
+        }
+
+        public init(accessibility: String) {
+            self.accessibility = accessibility
+        }
+        #endif
+
         public override func loadItem(key: String) -> Data? {
             var query = queryForItem(key: key)
             query[kSecReturnData as String] = true
@@ -115,7 +127,7 @@ public extension SessionStorage {
             #if os(macOS)
             values[kSecAttrAccess as String] = SecAccessCreateWithOwnerAndACL(getuid(), 0, SecAccessOwnerType(kSecUseOnlyUID), nil, nil)
             #else
-            values[kSecAttrAccessible as String] = kSecAttrAccessibleAfterFirstUnlock
+            values[kSecAttrAccessible as String] = accessibility
             #endif
 
             let query = queryForItem(key: key)

test/routes/Auth.swift

@@ -52,6 +52,20 @@ class TestAuth: XCTestCase {
         try checkUser(authResponse.user)
     }
 
+    func testRefresh() async throws {
+        let descope = DescopeSDK.mock()
+
+        MockHTTP.push(body: authNoRefreshPayload) { request in
+            XCTAssertEqual(request.httpMethod, "POST")
+            XCTAssertEqual(request.url?.absoluteString ?? "", "https://api.descope.com/v1/auth/refresh")
+            XCTAssertEqual(request.allHTTPHeaderFields?["Authorization"], "Bearer projId:foo")
+        }
+
+        let refreshResponse = try await descope.auth.refreshSession(refreshJwt: "foo")
+        XCTAssertEqual("bar", refreshResponse.sessionToken.entityId)
+        XCTAssertNil(refreshResponse.refreshToken)
+    }
+
     func checkUser(_ user: DescopeUser) throws {
         XCTAssertEqual("userId", user.userId)
         XCTAssertFalse(user.isVerifiedPhone)
@@ -93,6 +107,15 @@ private let authPayload = """
 }
 """
 
+private let authNoRefreshPayload = """
+{
+    "sessionJwt": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJiYXIiLCJuYW1lIjoiU3dpZnR5IE1jQXBwbGVzIiwiaWF0IjoxNTE2MjM5MDIyLCJpc3MiOiJmb28iLCJleHAiOjE2MDMxNzY2MTQsInBlcm1pc3Npb25zIjpbImQiLCJlIl0sInJvbGVzIjpbInVzZXIiXSwidGVuYW50cyI6eyJ0ZW5hbnQiOnsicGVybWlzc2lvbnMiOlsiYSIsImIiLCJjIl0sInJvbGVzIjpbImFkbWluIl19fX0.LEcNdzkdOXlzxcVNhvlqOIoNwzgYYfcDv1_vzF3awF8",
+    "refreshJwt": "",
+    "user": \(userPayload),
+    "firstSeen": false
+}
+"""
+
 private let tenantsPayload = """
 {
     "tenants": [