[Woo POS][Barcodes] Analytics for scan performance (#15900)

Author: staskus

WooCommerce/Classes/Analytics/TracksProvider.swift

@@ -151,6 +151,8 @@ private extension TracksProvider {
             WooAnalyticsStat.pointOfSaleBarcodeScanningMenuItemTapped,
             WooAnalyticsStat.pointOfSaleBarcodeScanningExplanationDialogShown,
             WooAnalyticsStat.pointOfSaleBarcodeScannerSetupFlowShown,
+            WooAnalyticsStat.pointOfSaleBarcodeScanningSuccess,
+            WooAnalyticsStat.pointOfSaleBarcodeScanningFailed,
 
             // Order
             WooAnalyticsStat.orderCreationSuccess,

WooCommerce/Classes/Analytics/WooAnalyticsStat.swift

@@ -1306,6 +1306,8 @@ enum WooAnalyticsStat: String {
     case pointOfSaleBarcodeScanningMenuItemTapped = "barcode_scanning_menu_item_tapped"
     case pointOfSaleBarcodeScanningExplanationDialogShown = "barcode_scanning_explanation_dialog_shown"
     case pointOfSaleBarcodeScannerSetupFlowShown = "barcode_scanner_setup_flow_shown"
+    case pointOfSaleBarcodeScanningSuccess = "barcode_scanned"
+    case pointOfSaleBarcodeScanningFailed = "barcode_scanning_failed"
 
     // MARK: Custom Fields events
     case productDetailCustomFieldsTapped = "product_detail_custom_fields_tapped"

WooCommerce/Classes/POS/Analytics/WooAnalyticsEvent+PointOfSale.swift

@@ -31,6 +31,9 @@ extension WooAnalyticsEvent {
             static let countryCode = "country"
             static let paymentMethodType = "payment_method_type"
             static let gatewayID = "plugin_slug"
+            static let scanDurationMs = "scan_duration_ms"
+            static let barcodeLength = "barcode_length"
+            static let failReason = "fail_reason"
         }
 
         static func paymentsOnboardingShown() -> WooAnalyticsEvent {
@@ -194,6 +197,23 @@ extension WooAnalyticsEvent {
                                 Key.totalItems: "\(totalItems)"
                               ])
         }
+
+        static func barcodeScanningSuccess(scanDurationMs: Int, barcodeLength: Int) -> WooAnalyticsEvent {
+            WooAnalyticsEvent(statName: .pointOfSaleBarcodeScanningSuccess,
+                              properties: [
+                                Key.scanDurationMs: "\(scanDurationMs)",
+                                Key.barcodeLength: "\(barcodeLength)"
+                              ])
+        }
+
+        static func barcodeScanningFailed(scanDurationMs: Int, barcodeLength: Int, failReason: String) -> WooAnalyticsEvent {
+            WooAnalyticsEvent(statName: .pointOfSaleBarcodeScanningFailed,
+                              properties: [
+                                Key.scanDurationMs: "\(scanDurationMs)",
+                                Key.barcodeLength: "\(barcodeLength)",
+                                Key.failReason: failReason
+                              ])
+        }
     }
 }
 

WooCommerce/Classes/POS/Presentation/Barcode Scanning/GameControllerBarcodeObserver.swift

@@ -88,7 +88,12 @@ final class GameControllerBarcodeObserver {
         cleanupKeyboard()
 
         coalescedKeyboard = keyboard
-        barcodeParser = GameControllerBarcodeParser(configuration: configuration, onScan: onScan)
+        barcodeParser = GameControllerBarcodeParser(
+            configuration: configuration,
+            onScan: { [weak self] result in
+                self?.handleScanResult(result)
+            }
+        )
 
         keyboard.keyboardInput?.keyChangedHandler = { [weak self] _, _, keyCode, pressed in
             guard let self = self else { return }
@@ -112,4 +117,29 @@ final class GameControllerBarcodeObserver {
         barcodeParser = nil
         isShiftPressed = false
     }
+
+    private func handleScanResult(_ result: HIDBarcodeParserResult) {
+        trackAnalyticsEvent(for: result)
+        onScan(result.asResult)
+    }
+
+    private func trackAnalyticsEvent(for result: HIDBarcodeParserResult) {
+        switch result {
+        case .success(let barcode, let scanDurationMs):
+            ServiceLocator.analytics.track(
+                event: WooAnalyticsEvent.PointOfSale.barcodeScanningSuccess(
+                    scanDurationMs: scanDurationMs,
+                    barcodeLength: barcode.count
+                )
+            )
+        case .failure(let error, let scanDurationMs):
+            ServiceLocator.analytics.track(
+                event: WooAnalyticsEvent.PointOfSale.barcodeScanningFailed(
+                    scanDurationMs: scanDurationMs,
+                    barcodeLength: error.barcode.count,
+                    failReason: error.analyticsReason
+                )
+            )
+        }
+    }
 }

WooCommerce/Classes/POS/Presentation/Barcode Scanning/GameControllerBarcodeParser.swift

@@ -8,15 +8,16 @@ final class GameControllerBarcodeParser {
     /// Configuration for the barcode scanner
     let configuration: HIDBarcodeParserConfiguration
     /// Callback that is triggered when a barcode scan completes (success or failure)
-    let onScan: (Result<String, Error>) -> Void
+    let onScan: (HIDBarcodeParserResult) -> Void
 
     private let timeProvider: TimeProvider
 
     private var buffer = ""
     private var lastKeyPressTime: Date?
+    private var scanStartTime: Date?
 
     init(configuration: HIDBarcodeParserConfiguration,
-         onScan: @escaping (Result<String, Error>) -> Void,
+         onScan: @escaping (HIDBarcodeParserResult) -> Void,
          timeProvider: TimeProvider = DefaultTimeProvider()) {
         self.configuration = configuration
         self.onScan = onScan
@@ -41,6 +42,12 @@ final class GameControllerBarcodeParser {
         } else {
             guard !excludedKeyCodes.contains(keyCode) else { return }
             checkForTimeoutBetweenKeystrokes()
+
+            // Start timing on first character
+            if buffer.isEmpty {
+                scanStartTime = timeProvider.now()
+            }
+
             buffer.append(character)
         }
     }
@@ -69,7 +76,10 @@ final class GameControllerBarcodeParser {
 
         if let lastTime = lastKeyPressTime,
            currentTime.timeIntervalSince(lastTime) > configuration.maximumInterCharacterTime {
-            onScan(.failure(HIDBarcodeParserError.timedOut(barcode: buffer)))
+            let scanDurationMs = calculateScanDurationMs()
+            let result = HIDBarcodeParserResult.failure(error: HIDBarcodeParserError.timedOut(barcode: buffer), scanDurationMs: scanDurationMs)
+
+            onScan(result)
             resetScan()
         }
 
@@ -175,14 +185,24 @@ final class GameControllerBarcodeParser {
     private func resetScan() {
         buffer = ""
         lastKeyPressTime = nil
+        scanStartTime = nil
+    }
+
+    private func calculateScanDurationMs() -> Int {
+        guard let startTime = scanStartTime else { return 0 }
+        return Int(round(timeProvider.now().timeIntervalSince(startTime) * 1000))
     }
 
     private func processScan() {
         checkForTimeoutBetweenKeystrokes()
+        let scanDurationMs = calculateScanDurationMs()
+
         if buffer.count >= configuration.minimumBarcodeLength {
-            onScan(.success(buffer))
+            let result = HIDBarcodeParserResult.success(barcode: buffer, scanDurationMs: scanDurationMs)
+            onScan(result)
         } else {
-            onScan(.failure(HIDBarcodeParserError.scanTooShort(barcode: buffer)))
+            let result = HIDBarcodeParserResult.failure(error: HIDBarcodeParserError.scanTooShort(barcode: buffer), scanDurationMs: scanDurationMs)
+            onScan(result)
         }
         resetScan()
     }
@@ -211,4 +231,34 @@ struct HIDBarcodeParserConfiguration {
 enum HIDBarcodeParserError: Error {
     case scanTooShort(barcode: String)
     case timedOut(barcode: String)
+
+    var analyticsReason: String {
+        switch self {
+        case .scanTooShort:
+            return "too_short"
+        case .timedOut:
+            return "no_terminator"
+        }
+    }
+
+    var barcode: String {
+        switch self {
+        case .scanTooShort(let barcode), .timedOut(let barcode):
+            return barcode
+        }
+    }
+}
+
+enum HIDBarcodeParserResult {
+    case success(barcode: String, scanDurationMs: Int)
+    case failure(error: HIDBarcodeParserError, scanDurationMs: Int)
+
+    var asResult: Result<String, Error> {
+        switch self {
+        case .success(let barcode, _):
+            return .success(barcode)
+        case .failure(let error, _):
+            return .failure(error)
+        }
+    }
 }