feat: Monitor barcode scanning performance (#4651)

Monitor how long the barcode scanner took #4622

app/src/main/java/openfoodfacts/github/scrachx/openfood/analytics/AnalyticsEvent.kt

@@ -8,6 +8,8 @@ sealed class AnalyticsEvent(val category: String, val action: String, val name:
 
     object ProductSearchStart : AnalyticsEvent("search", "started", null, null)
 
+    data class BarcodeDecoder(val success: Boolean = false, val duration: Float = 0f) : AnalyticsEvent("scanner", "scanning", success.toString(), duration)
+
     data class ScannedBarcode(val barcode: String) : AnalyticsEvent("scanner", "scanned", barcode, null)
 
     data class ScannedBarcodeResultExpanded(val barcode: String?) :

app/src/main/java/openfoodfacts/github/scrachx/openfood/analytics/AnalyticsTrackingEvent.kt

@@ -0,0 +1,19 @@
+package openfoodfacts.github.scrachx.openfood.analytics
+
+import android.app.Activity
+import java.util.concurrent.TimeUnit
+import kotlin.time.Duration.Companion.milliseconds
+
+fun Activity.startTrackEvent(event: AnalyticsEvent): AnalyticsTrackingEvent {
+    return AnalyticsTrackingEvent(event = event)
+}
+
+data class AnalyticsTrackingEvent(
+    val startDate: Long = System.currentTimeMillis(),
+    val event: AnalyticsEvent
+) {
+
+    fun computeDurationInSeconds(): Float =
+        (System.currentTimeMillis() - startDate).milliseconds.inWholeSeconds.toFloat()
+
+}

app/src/main/java/openfoodfacts/github/scrachx/openfood/features/scan/ContinuousScanActivity.kt

@@ -55,9 +55,7 @@ import kotlinx.coroutines.withContext
 import openfoodfacts.github.scrachx.openfood.AppFlavor
 import openfoodfacts.github.scrachx.openfood.AppFlavor.Companion.isFlavors
 import openfoodfacts.github.scrachx.openfood.R
-import openfoodfacts.github.scrachx.openfood.analytics.AnalyticsEvent
-import openfoodfacts.github.scrachx.openfood.analytics.AnalyticsView
-import openfoodfacts.github.scrachx.openfood.analytics.MatomoAnalytics
+import openfoodfacts.github.scrachx.openfood.analytics.*
 import openfoodfacts.github.scrachx.openfood.databinding.ActivityContinuousScanBinding
 import openfoodfacts.github.scrachx.openfood.features.images.manage.ImagesManageActivity
 import openfoodfacts.github.scrachx.openfood.features.product.edit.ProductEditActivity
@@ -69,6 +67,7 @@ import openfoodfacts.github.scrachx.openfood.features.product.view.summary.Abstr
 import openfoodfacts.github.scrachx.openfood.features.product.view.summary.IngredientAnalysisTagsAdapter
 import openfoodfacts.github.scrachx.openfood.features.product.view.summary.SummaryProductPresenter
 import openfoodfacts.github.scrachx.openfood.features.shared.BaseActivity
+import openfoodfacts.github.scrachx.openfood.features.simplescan.SimpleScanViewModel
 import openfoodfacts.github.scrachx.openfood.listeners.CommonBottomListenerInstaller.installBottomNavigation
 import openfoodfacts.github.scrachx.openfood.listeners.CommonBottomListenerInstaller.selectNavigationItem
 import openfoodfacts.github.scrachx.openfood.models.Barcode
@@ -126,6 +125,7 @@ class ContinuousScanActivity : BaseActivity(), IProductView {
 
     @Inject
     lateinit var matomoAnalytics: MatomoAnalytics
+    private var trackingEvent: AnalyticsTrackingEvent? = null
 
     @Inject
     lateinit var sharedPreferences: SharedPreferences
@@ -557,6 +557,7 @@ class ContinuousScanActivity : BaseActivity(), IProductView {
             cameraView.onResume()
         }
         matomoAnalytics.trackView(AnalyticsView.Scanner)
+        trackingEvent = startTrackEvent(AnalyticsEvent.BarcodeDecoder())
     }
 
     override fun onPostResume() {
@@ -573,6 +574,15 @@ class ContinuousScanActivity : BaseActivity(), IProductView {
     override fun onPause() {
         cameraView.stopCameraPreview()
         super.onPause()
+
+        trackingEvent?.let {
+            matomoAnalytics.trackEvent(
+                AnalyticsEvent.BarcodeDecoder(
+                    success = isBarcodeValid(lastBarcode),
+                    duration = it.computeDurationInSeconds(),
+                )
+            )
+        }
     }
 
     override fun onStop() {

app/src/main/java/openfoodfacts/github/scrachx/openfood/features/simplescan/SimpleScanActivity.kt

@@ -20,13 +20,18 @@ import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.onEach
 import logcat.logcat
 import openfoodfacts.github.scrachx.openfood.R
+import openfoodfacts.github.scrachx.openfood.analytics.AnalyticsEvent
+import openfoodfacts.github.scrachx.openfood.analytics.AnalyticsTrackingEvent
+import openfoodfacts.github.scrachx.openfood.analytics.MatomoAnalytics
+import openfoodfacts.github.scrachx.openfood.analytics.startTrackEvent
 import openfoodfacts.github.scrachx.openfood.databinding.ActivitySimpleScanBinding
 import openfoodfacts.github.scrachx.openfood.features.scan.CameraView
 import openfoodfacts.github.scrachx.openfood.features.simplescan.SimpleScanActivityContract.Companion.KEY_SCANNED_BARCODE
 import openfoodfacts.github.scrachx.openfood.features.simplescan.SimpleScanViewModel.SideEffect.BarcodeDetected
 import openfoodfacts.github.scrachx.openfood.features.simplescan.SimpleScanViewModel.SideEffect.ScanTrouble
 import openfoodfacts.github.scrachx.openfood.models.CameraState
 import java.util.concurrent.atomic.AtomicBoolean
+import javax.inject.Inject
 
 @AndroidEntryPoint
 class SimpleScanActivity : AppCompatActivity() {
@@ -37,6 +42,10 @@ class SimpleScanActivity : AppCompatActivity() {
     private lateinit var cameraView: CameraView<*>
     private val scannerInitialized = AtomicBoolean(false)
 
+    @Inject
+    lateinit var matomoAnalytics: MatomoAnalytics
+    private var trackingEvent: AnalyticsTrackingEvent? = null
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         binding = ActivitySimpleScanBinding.inflate(layoutInflater)
@@ -79,11 +88,21 @@ class SimpleScanActivity : AppCompatActivity() {
     override fun onResume() {
         super.onResume()
         startScanning()
+        trackingEvent = startTrackEvent(AnalyticsEvent.BarcodeDecoder())
     }
 
     override fun onPause() {
         super.onPause()
         stopScanning()
+
+        trackingEvent?.let {
+            matomoAnalytics.trackEvent(
+                AnalyticsEvent.BarcodeDecoder(
+                    success = viewModel.sideEffectsFlow.replayCache.lastOrNull() is SimpleScanViewModel.SideEffect.BarcodeDetected,
+                    duration = it.computeDurationInSeconds(),
+                )
+            )
+        }
     }
 
     override fun onWindowFocusChanged(hasFocus: Boolean) {

app/src/test/java/openfoodfacts/github/scrachx/openfood/features/simplescan/SimpleScanViewModelTest.kt

@@ -36,7 +36,6 @@ class SimpleScanViewModelTest {
         whenever(prefsRepository.mlScannerEnabled).doReturn(false)
         whenever(prefsRepository.cameraPref).doReturn(CameraState.Back)
 
-
         viewModel = SimpleScanViewModel(prefsRepository, dispatchers)
     }