From 2d965772e782c47a02d7c24917d209a56a80cfbb Mon Sep 17 00:00:00 2001
From: Angelo Stavrow <contact@angelostavrow.com>
Date: Fri, 20 Aug 2021 17:13:01 -0400
Subject: [PATCH] Add Keychain-related errors and throw from Keychain extension

---
 .../Extensions/WriteFreelyModel+Keychain.swift | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/Shared/Extensions/WriteFreelyModel+Keychain.swift b/Shared/Extensions/WriteFreelyModel+Keychain.swift
index fd37506..f039e31 100644
--- a/Shared/Extensions/WriteFreelyModel+Keychain.swift
+++ b/Shared/Extensions/WriteFreelyModel+Keychain.swift
@@ -1,7 +1,14 @@
 import Foundation
 
 extension WriteFreelyModel {
-    func saveTokenToKeychain(_ token: String, username: String?, server: String) {
+
+    enum WFKeychainError: Error {
+        case saveToKeychainFailed
+        case purgeFromKeychainFailed
+        case fetchFromKeychainFailed
+    }
+
+    func saveTokenToKeychain(_ token: String, username: String?, server: String) throws {
         let query: [String: Any] = [
             kSecClass as String: kSecClassGenericPassword,
             kSecValueData as String: token.data(using: .utf8)!,
@@ -10,7 +17,7 @@ extension WriteFreelyModel {
         ]
         let status = SecItemAdd(query as CFDictionary, nil)
         guard status == errSecDuplicateItem || status == errSecSuccess else {
-            fatalError("Error storing in Keychain with OSStatus: \(status)")
+            throw WFKeychainError.saveToKeychainFailed
         }
     }
 
@@ -22,11 +29,11 @@ extension WriteFreelyModel {
         ]
         let status = SecItemDelete(query as CFDictionary)
         guard status == errSecSuccess || status == errSecItemNotFound else {
-            fatalError("Error deleting from Keychain with OSStatus: \(status)")
+            throw WFKeychainError.purgeFromKeychainFailed
         }
     }
 
-    func fetchTokenFromKeychain(username: String?, server: String) -> String? {
+    func fetchTokenFromKeychain(username: String?, server: String) throws -> String? {
         let query: [String: Any] = [
             kSecClass as String: kSecClassGenericPassword,
             kSecAttrAccount as String: username ?? "anonymous",
@@ -41,7 +48,7 @@ extension WriteFreelyModel {
             return nil
         }
         guard status == errSecSuccess else {
-            fatalError("Error fetching from Keychain with OSStatus: \(status)")
+            throw WFKeychainError.fetchFromKeychainFailed
         }
         guard let existingSecItem = secItem as? [String: Any],
               let tokenData = existingSecItem[kSecValueData as String] as? Data,
@@ -50,4 +57,5 @@ extension WriteFreelyModel {
         }
         return token
     }
+
 }