add liveness events (#133)

Author: atierian

AmplifyPlugins/Predictions/AWSPredictionsPlugin/Liveness/Events/Date+EpochMillis.swift

@@ -0,0 +1,14 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+import Foundation
+
+extension Date {
+    var epochMilliseconds: UInt64 {
+        UInt64(self.timeIntervalSince1970 * 1_000)
+    }
+}

AmplifyPlugins/Predictions/AWSPredictionsPlugin/Liveness/Events/LivenessCompletedEvent.swift

@@ -0,0 +1,19 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+import Foundation
+
+@_spi(PredictionsFaceLiveness)
+public struct CompletedEvent<T> {
+    public init(initialEvent: T, endTimestamp: UInt64) {
+        self.initialEvent = initialEvent
+        self.endTimestamp = endTimestamp
+    }
+
+    let initialEvent: T
+    let endTimestamp: UInt64
+}

AmplifyPlugins/Predictions/AWSPredictionsPlugin/Liveness/Events/LivenessEvent.swift

@@ -0,0 +1,60 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+import Foundation
+
+@_spi(PredictionsFaceLiveness)
+public struct LivenessEvent<T> {
+    let payload: Data
+    let eventKind: LivenessEventKind
+    let eventTypeHeader: String
+}
+
+@_spi(PredictionsFaceLiveness)
+public enum LivenessEventKind {
+    public struct Server: Hashable {
+        public static let challenge = Server()
+        public static let disconnect = Server()
+    }
+    case server(Server)
+
+    public struct Client: Equatable {
+        let id: UInt8
+
+        public static let initialFaceDetected = Client(id: 0)
+        public static let video = Client(id: 1)
+        public static let freshness = Client(id: 2)
+        public static let final = Client(id: 3)
+    }
+    case client(Client)
+}
+
+extension LivenessEventKind: CustomDebugStringConvertible {
+    public var debugDescription: String {
+        switch self {
+        case .server(.challenge): return ".server(.challenge)"
+        case .server(.disconnect): return ".server(.disconnect)"
+        case .client(.initialFaceDetected): return ".client(.initialFaceDetected)"
+        case .client(.video): return ".client(.video)"
+        case .client(.freshness): return ".client(.freshness)"
+        case .client(.final): return ".client(.final)"
+        default: return "unknown"
+        }
+    }
+}
+
+extension LivenessEvent: CustomDebugStringConvertible {
+    public var debugDescription: String {
+        return """
+        LivenessEvent<\(T.self)>(
+            payload: \(payload),
+            eventKind: \(eventKind),
+            eventTypeHeader: \(eventTypeHeader)
+        )
+        """
+    }
+}

AmplifyPlugins/Predictions/AWSPredictionsPlugin/Liveness/Events/LivenessFaceDetectionEvent.swift

@@ -0,0 +1,19 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+import Foundation
+
+@_spi(PredictionsFaceLiveness)
+public struct FaceDetection {
+    let boundingBox: FaceLivenessSession.BoundingBox
+    let startTimestamp: UInt64
+
+    public init(boundingBox: FaceLivenessSession.BoundingBox, startTimestamp: UInt64) {
+        self.boundingBox = boundingBox
+        self.startTimestamp = startTimestamp
+    }
+}

AmplifyPlugins/Predictions/AWSPredictionsPlugin/Liveness/Events/LivenessFinalCientEvent.swift

@@ -0,0 +1,57 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+import Foundation
+
+@_spi(PredictionsFaceLiveness)
+public struct FinalClientEvent {
+    public init(
+        initialClientEvent: InitialClientEvent,
+        targetFace: CompletedEvent<FaceDetection>,
+        videoEndTimeStamp: UInt64
+    ) {
+        self.initialClientEvent = initialClientEvent
+        self.targetFace = targetFace
+        self.videoEndTimeStamp = videoEndTimeStamp
+    }
+
+    let initialClientEvent: InitialClientEvent
+    let targetFace: CompletedEvent<FaceDetection>
+    let videoEndTimeStamp: UInt64
+}
+
+extension LivenessEvent where T == FinalClientEvent {
+    @_spi(PredictionsFaceLiveness)
+    public static func final(event: FinalClientEvent) throws -> Self {
+
+        let clientEvent = ClientSessionInformationEvent(
+            challenge: .init(
+                faceMovementAndLightChallenge: .init(
+                    challengeID: event.initialClientEvent.challengeID,
+                    targetFace: .init(
+                        boundingBox: .init(boundingBox: event.targetFace.initialEvent.boundingBox),
+                        faceDetectedInTargetPositionStartTimestamp: event.targetFace.initialEvent.startTimestamp,
+                        faceDetectedInTargetPositionEndTimestamp: event.targetFace.endTimestamp
+                    ),
+                    initialFace: .init(
+                        boundingBox: .init(boundingBox: event.initialClientEvent.initialFaceLocation.boundingBox),
+                        initialFaceDetectedTimeStamp: event.initialClientEvent.initialFaceLocation.startTimestamp
+                    ),
+                    videoStartTimestamp: nil,
+                    colorDisplayed: nil,
+                    videoEndTimeStamp: Date().epochMilliseconds
+                )
+            )
+        )
+        let payload = try JSONEncoder().encode(clientEvent)
+        return .init(
+            payload: payload,
+            eventKind: .client(.final),
+            eventTypeHeader: "ClientSessionInformationEvent"
+        )
+    }
+}

AmplifyPlugins/Predictions/AWSPredictionsPlugin/Liveness/Events/LivenessFreshnessEvent.swift

@@ -0,0 +1,54 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+import Foundation
+
+@_spi(PredictionsFaceLiveness)
+public struct FreshnessEvent {
+    let challengeID: String
+    let color: [Int]
+    let sequenceNumber: Int
+    let timestamp: UInt64
+    let previousColor: [Int]
+
+    public init(challengeID: String, color: [Int], sequenceNumber: Int, timestamp: UInt64, previousColor: [Int]) {
+        self.challengeID = challengeID
+        self.color = color
+        self.sequenceNumber = sequenceNumber
+        self.timestamp = timestamp
+        self.previousColor = previousColor
+    }
+}
+
+extension LivenessEvent where T == FreshnessEvent {
+    @_spi(PredictionsFaceLiveness)
+    public static func freshness(event: FreshnessEvent) throws -> Self {
+        let clientEvent = ClientSessionInformationEvent(
+            challenge: .init(
+                faceMovementAndLightChallenge: .init(
+                    challengeID: event.challengeID,
+                    targetFace: nil,
+                    initialFace: nil,
+                    videoStartTimestamp: nil,
+                    colorDisplayed: .init(
+                        currentColor: .init(rgb: event.color),
+                        sequenceNumber: event.sequenceNumber,
+                        currentColorStartTimeStamp: event.timestamp,
+                        previousColor: .init(rgb: event.previousColor)
+                    ),
+                    videoEndTimeStamp: nil
+                )
+            )
+        )
+        let payload = try JSONEncoder().encode(clientEvent)
+        return .init(
+            payload: payload,
+            eventKind: .client(.freshness),
+            eventTypeHeader: "ClientSessionInformationEvent"
+        )
+    }
+}

AmplifyPlugins/Predictions/AWSPredictionsPlugin/Liveness/Events/LivenessInitialClientEvent.swift

@@ -0,0 +1,55 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+import Foundation
+
+@_spi(PredictionsFaceLiveness)
+public struct InitialClientEvent {
+    public init(
+        challengeID: String,
+        initialFaceLocation: FaceDetection,
+        videoStartTime: UInt64
+    ) {
+        self.challengeID = challengeID
+        self.initialFaceLocation = initialFaceLocation
+        self.videoStartTimestamp = videoStartTime
+    }
+
+    let challengeID: String
+    let initialFaceLocation: FaceDetection
+    let videoStartTimestamp: UInt64
+}
+
+extension LivenessEvent where T == InitialClientEvent {
+    @_spi(PredictionsFaceLiveness)
+    public static func initialFaceDetected(event: InitialClientEvent) throws -> Self {
+        let initialFace = InitialFace(
+            boundingBox: .init(boundingBox: event.initialFaceLocation.boundingBox),
+            initialFaceDetectedTimeStamp: event.initialFaceLocation.startTimestamp
+        )
+
+        let clientSessionInformationEvent = ClientSessionInformationEvent(
+            challenge: .init(
+                faceMovementAndLightChallenge: .init(
+                    challengeID: event.challengeID,
+                    targetFace: nil,
+                    initialFace: initialFace,
+                    videoStartTimestamp: event.videoStartTimestamp,
+                    colorDisplayed: nil,
+                    videoEndTimeStamp: nil
+                )
+            )
+        )
+
+        let payload = try JSONEncoder().encode(clientSessionInformationEvent)
+        return .init(
+            payload: payload,
+            eventKind: .client(.initialFaceDetected),
+            eventTypeHeader: "ClientSessionInformationEvent"
+        )
+    }
+}

AmplifyPlugins/Predictions/AWSPredictionsPlugin/Liveness/Events/LivenessVideoEvent.swift

@@ -0,0 +1,35 @@
+//
+// Copyright Amazon.com Inc. or its affiliates.
+// All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+import Foundation
+
+@_spi(PredictionsFaceLiveness)
+public struct VideoEvent {
+    let chunk: Data
+    let timestamp: UInt64
+
+    public init(chunk: Data, timestamp: UInt64) {
+        self.chunk = chunk
+        self.timestamp = timestamp
+    }
+}
+
+extension LivenessEvent where T == VideoEvent {
+    @_spi(PredictionsFaceLiveness)
+    public static func video(event: VideoEvent) throws -> Self {
+        let clientEvent = LivenessVideoEvent(
+            timestampMillis: event.timestamp,
+            videoChunk: event.chunk
+        )
+        let payload = try JSONEncoder().encode(clientEvent)
+        return .init(
+            payload: payload,
+            eventKind: .client(.video),
+            eventTypeHeader: "VideoEvent"
+        )
+    }
+}