Modularize base16 encoding

Base16/.gitignore

@@ -0,0 +1,5 @@
+.DS_Store
+/.build
+/Packages
+/*.xcodeproj
+xcuserdata/

Base16/Package.swift

@@ -0,0 +1,22 @@
+// swift-tools-version:5.3
+// The swift-tools-version declares the minimum version of Swift required to build this package.
+
+import PackageDescription
+
+let package = Package(
+    name: "Base16",
+    products: [
+        .library(
+            name: "Base16",
+            targets: ["Base16"])
+    ],
+    dependencies: [],
+    targets: [
+        .target(
+            name: "Base16",
+            dependencies: []),
+        .testTarget(
+            name: "Base16Tests",
+            dependencies: ["Base16"])
+    ]
+)

Base16/Sources/Base16/Data+Base16.swift

@@ -0,0 +1,68 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+import Foundation
+
+public enum Base16EncodingError: Error {
+    case invalidLength
+    case invalidByteString(String)
+    case invalidStringEncoding
+}
+
+public extension Data {
+    enum Base16EncodingOptions {
+        case uppercase
+    }
+
+    func base16EncodedString(options: [Base16EncodingOptions] = []) -> String {
+        map { String(format: Self.format(options: options), $0) }.joined()
+    }
+
+    func base16EncodedData(options: [Base16EncodingOptions] = []) -> Data {
+        Data(base16EncodedString(options: options).utf8)
+    }
+
+    init(base16Encoded string: String) throws {
+        let stringLength = string.count
+
+        guard stringLength % 2 == 0 else {
+            throw Base16EncodingError.invalidLength
+        }
+
+        var data = [UInt8]()
+
+        data.reserveCapacity(stringLength / 2)
+
+        var i = string.startIndex
+
+        while i != string.endIndex {
+            let j = string.index(i, offsetBy: 2)
+            let byteString = string[i..<j]
+
+            guard let byte = UInt8(byteString, radix: 16) else {
+                throw Base16EncodingError.invalidByteString(String(byteString))
+            }
+
+            data.append(byte)
+            i = j
+        }
+
+        self = Data(data)
+    }
+
+    init(base16Encoded data: Data) throws {
+        guard let string = String(data: data, encoding: .utf8) else {
+            throw Base16EncodingError.invalidStringEncoding
+        }
+
+        try self.init(base16Encoded: string)
+    }
+}
+
+private extension Data {
+    static let lowercaseBase16Format = "%02.2hhx"
+    static let uppercaseBase16Format = "%02.2hhX"
+
+    static func format(options: [Base16EncodingOptions]) -> String {
+        options.contains(.uppercase) ? uppercaseBase16Format : lowercaseBase16Format
+    }
+}

Base16/Tests/Base16Tests/Base16Tests.swift

@@ -0,0 +1,101 @@
+// Copyright © 2020 Metabolist. All rights reserved.
+
+@testable import Base16
+import XCTest
+
+final class Base16Tests: XCTestCase {
+    let testData = Data([182, 239, 215, 173, 251, 168, 76, 252,
+                         140, 7, 39, 163, 56, 255, 171, 35,
+                         121, 205, 26, 252, 53, 166, 159, 67,
+                         100, 70, 140, 79, 47, 26, 138, 209])
+    let testDataLowercaseString = "b6efd7adfba84cfc8c0727a338ffab2379cd1afc35a69f4364468c4f2f1a8ad1"
+    let testDataLowercaseStringData = Data([98, 54, 101, 102, 100, 55, 97, 100,
+                                            102, 98, 97, 56, 52, 99, 102, 99,
+                                            56, 99, 48, 55, 50, 55, 97, 51, 51,
+                                            56, 102, 102, 97, 98, 50, 51, 55,
+                                            57, 99, 100, 49, 97, 102, 99, 51,
+                                            53, 97, 54, 57, 102, 52, 51, 54,
+                                            52, 52, 54, 56, 99, 52, 102, 50,
+                                            102, 49, 97, 56, 97, 100, 49])
+    let testDataUppercaseString = "B6EFD7ADFBA84CFC8C0727A338FFAB2379CD1AFC35A69F4364468C4F2F1A8AD1"
+    let testDataUppercaseStringData = Data([66, 54, 69, 70, 68, 55, 65, 68,
+                                            70, 66, 65, 56, 52, 67, 70, 67,
+                                            56, 67, 48, 55, 50, 55, 65, 51,
+                                            51, 56, 70, 70, 65, 66, 50, 51,
+                                            55, 57, 67, 68, 49, 65, 70, 67,
+                                            51, 53, 65, 54, 57, 70, 52, 51,
+                                            54, 52, 52, 54, 56, 67, 52, 70,
+                                            50, 70, 49, 65, 56, 65, 68, 49])
+
+    func testLowercaseString() {
+        XCTAssertEqual(testData.base16EncodedString(), testDataLowercaseString)
+    }
+
+    func testUppercaseString() {
+        XCTAssertEqual(testData.base16EncodedString(options: [.uppercase]),
+                       testDataUppercaseString)
+    }
+
+    func testLowercaseData() {
+        XCTAssertEqual(testData.base16EncodedData(), testDataLowercaseStringData)
+    }
+
+    func testUppercaseData() {
+        XCTAssertEqual(testData.base16EncodedData(options: [.uppercase]),
+                       testDataUppercaseStringData)
+    }
+
+    func testInitializationFromLowercaseString() throws {
+        XCTAssertEqual(try Data(base16Encoded: testDataLowercaseString), testData)
+    }
+
+    func testInitializationFromUppercaseString() throws {
+        XCTAssertEqual(try Data(base16Encoded: testDataUppercaseString), testData)
+    }
+
+    func testInitializationFromLowercaseData() throws {
+        XCTAssertEqual(try Data(base16Encoded: testDataLowercaseStringData), testData)
+    }
+
+    func testInitializationFromUppercaseData() throws {
+        XCTAssertEqual(try Data(base16Encoded: testDataUppercaseStringData), testData)
+    }
+
+    func testInvalidLength() throws {
+        let invalidLength = String(testDataLowercaseString.prefix(testDataLowercaseString.count - 1))
+
+        XCTAssertThrowsError(try Data(base16Encoded: invalidLength)) {
+            guard case Base16EncodingError.invalidLength = $0 else {
+                XCTFail("Expected invalid length error")
+
+                return
+            }
+        }
+    }
+
+    func testInvalidByteString() {
+        let invalidString = testDataLowercaseString.replacingOccurrences(of: "a", with: "z")
+
+        XCTAssertThrowsError(try Data(base16Encoded: invalidString)) {
+            guard case let Base16EncodingError.invalidByteString(invalidByteString) = $0 else {
+                XCTFail("Expected invalid byte string error")
+
+                return
+            }
+
+            XCTAssertEqual(invalidByteString, "zd")
+        }
+    }
+
+    func testInvalidStringEncoding() {
+        let invalidData = testDataLowercaseString.data(using: .utf16)!
+
+        XCTAssertThrowsError(try Data(base16Encoded: invalidData)) {
+            guard case Base16EncodingError.invalidStringEncoding = $0 else {
+                XCTFail("Expected string encoding error")
+
+                return
+            }
+        }
+    }
+}

DB/Sources/DB/Entities/Identity.swift

@@ -10,7 +10,7 @@ public struct Identity: Codable, Hashable, Identifiable {
     public let preferences: Identity.Preferences
     public let instance: Identity.Instance?
     public let account: Identity.Account?
-    public let lastRegisteredDeviceToken: String?
+    public let lastRegisteredDeviceToken: Data?
     public let pushSubscriptionAlerts: PushSubscription.Alerts
 }
 

DB/Sources/DB/Identity/IdentityDatabase.swift

@@ -116,7 +116,7 @@ public extension IdentityDatabase {
     }
 
     func updatePushSubscription(alerts: PushSubscription.Alerts,
-                                deviceToken: String? = nil,
+                                deviceToken: Data? = nil,
                                 forIdentityID identityID: UUID) -> AnyPublisher<Never, Error> {
         databaseQueue.writePublisher {
             let data = try IdentityRecord.databaseJSONEncoder(for: "pushSubscriptionAlerts").encode(alerts)
@@ -180,7 +180,7 @@ public extension IdentityDatabase {
             .eraseToAnyPublisher()
     }
 
-    func identitiesWithOutdatedDeviceTokens(deviceToken: String) -> AnyPublisher<[Identity], Error> {
+    func identitiesWithOutdatedDeviceTokens(deviceToken: Data) -> AnyPublisher<[Identity], Error> {
         databaseQueue.readPublisher(
             value: Self.identitiesRequest()
                 .filter(Column("lastRegisteredDeviceToken") != deviceToken)
@@ -221,7 +221,7 @@ private extension IdentityDatabase {
                     .references("instance", column: "uri")
                 t.column("preferences", .blob).notNull()
                 t.column("pushSubscriptionAlerts", .blob).notNull()
-                t.column("lastRegisteredDeviceToken", .text)
+                t.column("lastRegisteredDeviceToken", .blob)
             }
 
             try db.create(table: "account", ifNotExists: true) { t in

DB/Sources/DB/Identity/IdentityRecord.swift

@@ -10,7 +10,7 @@ struct IdentityRecord: Codable, Hashable, FetchableRecord, PersistableRecord {
     let lastUsedAt: Date
     let preferences: Identity.Preferences
     let instanceURI: String?
-    let lastRegisteredDeviceToken: String?
+    let lastRegisteredDeviceToken: Data?
     let pushSubscriptionAlerts: PushSubscription.Alerts
 }
 

Extensions/Data+Extensions.swift

@@ -1,9 +0,0 @@
-// Copyright © 2020 Metabolist. All rights reserved.
-
-import Foundation
-
-extension Data {
-    func hexEncodedString() -> String {
-        map { String(format: "%02hhx", $0) }.joined()
-    }
-}

Metatext.xcodeproj/project.pbxproj

@@ -41,7 +41,6 @@
 		D0C7D4D724F7616A001EBDBB /* UIColor+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0C7D46C24F76169001EBDBB /* UIColor+Extensions.swift */; };
 		D0C7D4D924F7616A001EBDBB /* KingfisherOptionsInfo+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0C7D46E24F76169001EBDBB /* KingfisherOptionsInfo+Extensions.swift */; };
 		D0C7D4DA24F7616A001EBDBB /* View+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0C7D46F24F76169001EBDBB /* View+Extensions.swift */; };
-		D0C7D4DC24F7616A001EBDBB /* Data+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0C7D47124F76169001EBDBB /* Data+Extensions.swift */; };
 		D0E2C1D124FD97F000854680 /* ViewModels in Frameworks */ = {isa = PBXBuildFile; productRef = D0E2C1D024FD97F000854680 /* ViewModels */; };
 		D0E5361C24E3EB4D00FB1CE1 /* NotificationService.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0E5361B24E3EB4D00FB1CE1 /* NotificationService.swift */; };
 		D0E5362024E3EB4D00FB1CE1 /* Notification Service Extension.appex in Embed App Extensions */ = {isa = PBXBuildFile; fileRef = D0E5361924E3EB4D00FB1CE1 /* Notification Service Extension.appex */; settings = {ATTRIBUTES = (RemoveHeadersOnCopy, ); }; };
@@ -87,6 +86,7 @@
 		D0666A2124C677B400F3F04B /* Tests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = Tests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		D0666A2524C677B400F3F04B /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		D085C3BB25008DEC008A6C5E /* DB */ = {isa = PBXFileReference; lastKnownFileType = folder; path = DB; sourceTree = "<group>"; };
+		D0AD03552505814D0085A466 /* Base16 */ = {isa = PBXFileReference; lastKnownFileType = folder; path = Base16; sourceTree = "<group>"; };
 		D0BDF66524FD7A6400C7FA1C /* ServiceLayer */ = {isa = PBXFileReference; lastKnownFileType = folder; path = ServiceLayer; sourceTree = "<group>"; };
 		D0BEB1F224F8EE8C001B0F04 /* AttachmentView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AttachmentView.swift; sourceTree = "<group>"; };
 		D0BEB1F624F9A84B001B0F04 /* LoadingTableFooterView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LoadingTableFooterView.swift; sourceTree = "<group>"; };
@@ -120,7 +120,6 @@
 		D0C7D46C24F76169001EBDBB /* UIColor+Extensions.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "UIColor+Extensions.swift"; sourceTree = "<group>"; };
 		D0C7D46E24F76169001EBDBB /* KingfisherOptionsInfo+Extensions.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "KingfisherOptionsInfo+Extensions.swift"; sourceTree = "<group>"; };
 		D0C7D46F24F76169001EBDBB /* View+Extensions.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "View+Extensions.swift"; sourceTree = "<group>"; };
-		D0C7D47124F76169001EBDBB /* Data+Extensions.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "Data+Extensions.swift"; sourceTree = "<group>"; };
 		D0D7C013250440610039AD6F /* CodableBloomFilter */ = {isa = PBXFileReference; lastKnownFileType = folder; path = CodableBloomFilter; sourceTree = "<group>"; };
 		D0E0F1E424FC49FC002C04BF /* Mastodon */ = {isa = PBXFileReference; lastKnownFileType = folder; path = Mastodon; sourceTree = "<group>"; };
 		D0E2C1CF24FD8BA400854680 /* ViewModels */ = {isa = PBXFileReference; lastKnownFileType = folder; path = ViewModels; sourceTree = "<group>"; };
@@ -183,6 +182,7 @@
 			isa = PBXGroup;
 			children = (
 				D0C7D45224F76169001EBDBB /* Assets.xcassets */,
+				D0AD03552505814D0085A466 /* Base16 */,
 				D0D7C013250440610039AD6F /* CodableBloomFilter */,
 				D085C3BB25008DEC008A6C5E /* DB */,
 				D0C7D46824F76169001EBDBB /* Extensions */,
@@ -291,7 +291,6 @@
 		D0C7D46824F76169001EBDBB /* Extensions */ = {
 			isa = PBXGroup;
 			children = (
-				D0C7D47124F76169001EBDBB /* Data+Extensions.swift */,
 				D0C7D46E24F76169001EBDBB /* KingfisherOptionsInfo+Extensions.swift */,
 				D0C7D46B24F76169001EBDBB /* NSMutableAttributedString+Extensions.swift */,
 				D0C7D46A24F76169001EBDBB /* String+Extensions.swift */,
@@ -493,7 +492,6 @@
 				D0C7D4A224F7616A001EBDBB /* NotificationTypesPreferencesView.swift in Sources */,
 				D0BEB1F724F9A84B001B0F04 /* LoadingTableFooterView.swift in Sources */,
 				D0C7D4D924F7616A001EBDBB /* KingfisherOptionsInfo+Extensions.swift in Sources */,
-				D0C7D4DC24F7616A001EBDBB /* Data+Extensions.swift in Sources */,
 				D0BEB1FF24F9E5BB001B0F04 /* ListsView.swift in Sources */,
 				D0C7D49724F7616A001EBDBB /* IdentitiesView.swift in Sources */,
 				D0C7D49824F7616A001EBDBB /* CustomEmojiText.swift in Sources */,

Secrets/Package.swift

@@ -14,12 +14,13 @@ let package = Package(
             targets: ["Secrets"])
     ],
     dependencies: [
+        .package(path: "Base16"),
         .package(path: "Keychain")
     ],
     targets: [
         .target(
             name: "Secrets",
-            dependencies: ["Keychain"]),
+            dependencies: ["Base16", "Keychain"]),
         .testTarget(
             name: "SecretsTests",
             dependencies: ["Secrets"])

Secrets/Sources/Secrets/Secrets.swift

@@ -1,5 +1,6 @@
 // Copyright © 2020 Metabolist. All rights reserved.
 
+import Base16
 import Foundation
 import Keychain
 
@@ -84,7 +85,7 @@ public extension Secrets {
             }
         }
 
-        return "x'\(passphraseData.uppercaseHexEncodedString())'"
+        return "x'\(passphraseData.base16EncodedString(options: [.uppercase]))'"
     }
 
     func deleteAllItems() throws {
@@ -225,9 +226,3 @@ private struct PushKey {
         kSecAttrKeyType as String: kSecAttrKeyTypeECSECPrimeRandom,
         kSecAttrKeySizeInBits as String: sizeInBits]
 }
-
-private extension Data {
-    func uppercaseHexEncodedString() -> String {
-        map { String(format: "%02hhX", $0) }.joined()
-    }
-}

ServiceLayer/Sources/ServiceLayer/Services/AllIdentitiesService.swift

@@ -77,7 +77,7 @@ public extension AllIdentitiesService {
             .eraseToAnyPublisher()
     }
 
-    func updatePushSubscriptions(deviceToken: String) -> AnyPublisher<Never, Error> {
+    func updatePushSubscriptions(deviceToken: Data) -> AnyPublisher<Never, Error> {
         identityDatabase.identitiesWithOutdatedDeviceTokens(deviceToken: deviceToken)
             .tryMap { identities -> [AnyPublisher<Never, Never>] in
                 try identities.map {

ServiceLayer/Sources/ServiceLayer/Services/IdentityService.swift

@@ -1,5 +1,6 @@
 // Copyright © 2020 Metabolist. All rights reserved.
 
+import Base16
 import Combine
 import DB
 import Foundation
@@ -167,7 +168,7 @@ public extension IdentityService {
             .eraseToAnyPublisher()
     }
 
-    func createPushSubscription(deviceToken: String, alerts: PushSubscription.Alerts) -> AnyPublisher<Never, Error> {
+    func createPushSubscription(deviceToken: Data, alerts: PushSubscription.Alerts) -> AnyPublisher<Never, Error> {
         let publicKey: String
         let auth: String
 
@@ -180,7 +181,7 @@ public extension IdentityService {
 
         let identityID = identity.id
         let endpoint = Self.pushSubscriptionEndpointURL
-            .appendingPathComponent(deviceToken)
+            .appendingPathComponent(deviceToken.base16EncodedString())
             .appendingPathComponent(identityID.uuidString)
 
         return mastodonAPIClient.request(

System/AppDelegate.swift

@@ -9,14 +9,14 @@ class AppDelegate: NSObject {
 }
 
 extension AppDelegate {
-    func registerForRemoteNotifications() -> AnyPublisher<String, Error> {
+    func registerForRemoteNotifications() -> AnyPublisher<Data, Error> {
         $application
             .compactMap { $0 }
             .handleEvents(receiveOutput: { $0.registerForRemoteNotifications() })
             .setFailureType(to: Error.self)
             .zip(remoteNotificationDeviceTokens)
             .first()
-            .map { $1.hexEncodedString() }
+            .map { $1 }
             .eraseToAnyPublisher()
     }
 }

ViewModels/Sources/ViewModels/RootViewModel.swift

@@ -10,11 +10,11 @@ public final class RootViewModel: ObservableObject {
     @Published private var mostRecentlyUsedIdentityID: UUID?
     private let allIdentitiesService: AllIdentitiesService
     private let userNotificationService: UserNotificationService
-    private let registerForRemoteNotifications: () -> AnyPublisher<String, Error>
+    private let registerForRemoteNotifications: () -> AnyPublisher<Data, Error>
     private var cancellables = Set<AnyCancellable>()
 
     public init(environment: AppEnvironment,
-                registerForRemoteNotifications: @escaping () -> AnyPublisher<String, Error>) throws {
+                registerForRemoteNotifications: @escaping () -> AnyPublisher<Data, Error>) throws {
         allIdentitiesService = try AllIdentitiesService(environment: environment)
         userNotificationService = UserNotificationService(environment: environment)
         self.registerForRemoteNotifications = registerForRemoteNotifications