Extract key importing logic and put it into separate class

passKit/Helpers/AppError.swift

@@ -6,7 +6,7 @@
 //  Copyright © 2017 Bob Sun. All rights reserved.
 //
 
-public enum AppError: Error {
+public enum AppError: Error, Equatable {
     case RepositoryNotSet
     case RepositoryRemoteBranchNotFound(_: String)
     case RepositoryBranchNotFound(_: String)

passKit/Helpers/KeyFileManager.swift

@@ -0,0 +1,40 @@
+//
+//  KeyFileManager.swift
+//  passKit
+//
+//  Created by Danny Moesch on 29.06.19.
+//  Copyright © 2019 Bob Sun. All rights reserved.
+//
+
+public class KeyFileManager {
+    public typealias KeyHandler = (Data, String) -> ()
+
+    public static let PublicPgp = KeyFileManager(keyType: PgpKeyType.PUBLIC)
+    public static let PrivatePgp = KeyFileManager(keyType: PgpKeyType.PRIVATE)
+
+    private let keyType: PgpKeyType
+    private let keyPath: String
+    private let keyHandler: KeyHandler
+
+    private convenience init(keyType: PgpKeyType) {
+        self.init(keyType: keyType, keyPath: keyType.getFileSharingPath())
+    }
+
+    public init(keyType: PgpKeyType, keyPath: String, keyHandler: @escaping KeyHandler = AppKeychain.add) {
+        self.keyType = keyType
+        self.keyPath = keyPath
+        self.keyHandler = keyHandler
+    }
+
+    public func importKeyAndDeleteFile() throws {
+        guard let keyFileContent = FileManager.default.contents(atPath: keyPath) else {
+            throw AppError.ReadingFile(URL(fileURLWithPath: keyPath).lastPathComponent)
+        }
+        keyHandler(keyFileContent, keyType.getKeychainKey())
+        try FileManager.default.removeItem(atPath: keyPath)
+    }
+    
+    public func doesKeyFileExist() -> Bool {
+        return FileManager.default.fileExists(atPath: keyPath)
+    }
+}

passKit/Helpers/PgpKeyType.swift

@@ -0,0 +1,30 @@
+//
+//  PgpKeyType.swift
+//  passKit
+//
+//  Created by Danny Moesch on 29.06.19.
+//  Copyright © 2019 Bob Sun. All rights reserved.
+//
+
+public enum PgpKeyType {
+    case PUBLIC
+    case PRIVATE
+
+    public func getKeychainKey() -> String {
+        switch self {
+        case .PUBLIC:
+            return "pgpPublicKey"
+        case .PRIVATE:
+            return "pgpPrivateKey"
+        }
+    }
+
+    func getFileSharingPath() -> String {
+        switch self {
+        case .PUBLIC:
+            return Globals.iTunesFileSharingPGPPublic
+        case .PRIVATE:
+            return Globals.iTunesFileSharingPGPPrivate
+        }
+    }
+}