Move to Bytes from Data, simplify result cases

Sources/App/DeviceResponse.swift

@@ -24,14 +24,10 @@ struct DeviceResponse {
         .init(event: .noBodyData)
     }
 
-    static var corruptkeyData: DeviceResponse {
-        .init(event: .corruptkeyData)
-    }
-
     static var operationInProgress: DeviceResponse {
         .init(event: .operationInProgress)
     }
-    
+
     /// The response to a key from the server
     let event: MessageResult
 
@@ -39,7 +35,7 @@ struct DeviceResponse {
     let response: Message?
 
     init?(_ buffer: ByteBuffer) {
-        guard let byte = buffer.getData(at: 0, length: 1) else {
+        guard let byte = buffer.getBytes(at: 0, length: 1) else {
             print("No bytes received from device")
             return nil
         }

Sources/App/Message.swift

@@ -1,7 +1,6 @@
 import Foundation
 import CryptoKit
 import NIOCore
-import Vapor
 
 struct Message: Equatable, Hashable {
 
@@ -20,9 +19,9 @@ struct Message: Equatable, Hashable {
             self.id = id
         }
 
-        init(decodeFrom data: Data) {
+        init<T: Sequence>(decodeFrom data: T) where T.Element == UInt8 {
-            self.time = UInt32(data: data[data.startIndex..<data.startIndex+4])
+            self.time = UInt32(data: data.prefix(4))
-            self.id = UInt32(data: data[data.startIndex+4..<data.startIndex+8])
+            self.id = UInt32(data: data.dropFirst(4))
         }
 
         static var length: Int {
@@ -59,16 +58,16 @@ struct Message: Equatable, Hashable {
     }
 
     init?(decodeFrom buffer: ByteBuffer) {
-        guard let data = buffer.getData(at: 0, length: Message.length) else {
+        guard let data = buffer.getBytes(at: 0, length: Message.length) else {
             return nil
         }
         self.init(decodeFrom: data)
     }
 
-    private init(decodeFrom data: Data) {
+    private init<T: Sequence>(decodeFrom data: T) where T.Element == UInt8 {
         let count = SHA256Digest.byteCount
-        self.mac = data[data.startIndex..<data.startIndex+count]
+        self.mac = Data(data.prefix(count))
-        self.content = .init(decodeFrom: data.advanced(by: count))
+        self.content = .init(decodeFrom: Array(data.dropFirst(count)))
     }
 
     func isValid(using key: SymmetricKey) -> Bool {
@@ -86,13 +85,12 @@ struct Message: Equatable, Hashable {
 
  extension UInt32 {
 
-    init(data: Data) {
+     init<T: Sequence>(data: T) where T.Element == UInt8 {
         self = data
             .reversed()
             .enumerated()
             .map { UInt32($0.element) << ($0.offset * 8) }
             .reduce(0, +)
-
     }
 
     var encoded: Data {

Sources/App/MessageResult.swift

@@ -4,41 +4,35 @@ import Foundation
  A result from sending a key to the device.
  */
 enum MessageResult: UInt8 {
-    
+
     /// Text content was received, although binary data was expected
     case textReceived = 1
-    
+
     /// A socket event on the device was unexpected (not binary data)
     case unexpectedSocketEvent = 2
-    
+
     /// The size of the payload (i.e. message) was invalid, or the data could not be read
     case invalidMessageData = 3
 
     /// The transmitted message could not be authenticated using the key
     case messageAuthenticationFailed = 4
-    
+
     /// The message time was not within the acceptable bounds
     case messageTimeMismatch = 5
-    
+
     /// A later key has been used, invalidating this key (to prevent replay attacks after blocked communication)
     case messageCounterInvalid = 6
-    
+
     /// The key was accepted by the device, and the door will be opened
     case messageAccepted = 7
 
 
-    /// The device produced an unknown error
-    case unknownDeviceError = 9
-    
     /// The request did not contain body data with the key
     case noBodyData = 10
-    
+
-    /// The body data could not be read
-    case corruptkeyData = 11
-    
     /// The device is not connected
     case deviceNotConnected = 12
-    
+
     /// The device did not respond within the timeout
     case deviceTimedOut = 13
 
@@ -47,7 +41,7 @@ enum MessageResult: UInt8 {
 }
 
 extension MessageResult: CustomStringConvertible {
-    
+
     var description: String {
         switch self {
         case .textReceived:
@@ -64,12 +58,8 @@ extension MessageResult: CustomStringConvertible {
             return "Message counter invalid"
         case .messageAccepted:
             return "Message accepted"
-        case .unknownDeviceError:
-            return "The device experienced an unknown error"
         case .noBodyData:
             return "No body data included in the request"
-        case .corruptkeyData:
-            return "Key data corrupted"
         case .deviceNotConnected:
             return "Device not connected"
         case .deviceTimedOut:

Sources/App/routes.swift

@@ -33,7 +33,7 @@ func routes(_ app: Application) throws {
     }
     
     /**
-     Post a key to the device for unlocking.
+     Post a message to the device for unlocking.
      
      The request returns one or `Message.length+1` bytes of data, where the first byte is the raw value of a `MessageResult`,
      and the optional following bytes contain the response message of the device. This request does not complete until either the device responds or the request times out. The timeout is specified by `KeyManagement.deviceTimeout`.
@@ -45,9 +45,9 @@ func routes(_ app: Application) throws {
     }
     
     /**
-     Start a new websocket connection for the client to receive table updates from the server
+     Start a new websocket connection for the device to receive messages from the server
      - Returns: Nothing
-     - Note: The first (and only) message from the client over the connection must be a valid session token.
+     - Note: The first message from the device over the connection must be a valid auth token.
      */
     app.webSocket(PublicAPI.socket.path) { req, socket in
         socket.onBinary { _, data in

Tests/AppTests/AppTests.swift

@@ -12,11 +12,11 @@ final class AppTests: XCTestCase {
 
     func testEncodingContent() {
         let input = Message.Content(time: 1234567890, id: 23456789)
-        let data = input.encoded
+        let data = input.bytes
         let output = Message.Content(decodeFrom: data)
         XCTAssertEqual(input, output)
-        let data2 = Data([42, 42]) + data
+        let data2 = [42, 42] + data
-        let output2 = Message.Content(decodeFrom: Data(data2[2...]))
+        let output2 = Message.Content(decodeFrom: data2[2...])
         XCTAssertEqual(input, output2)
     }
 
@@ -42,4 +42,12 @@ final class AppTests: XCTestCase {
         XCTAssertEqual(decoded!, input)
         XCTAssertEqual(content, input.content)
     }
+
+    func testMessageTransmission() throws {
+        let app = Application(.testing)
+        defer { app.shutdown() }
+        try configure(app)
+
+        // How to open a socket via request?
+    }
 }