RUM-7171 Implement the basic logic for interaction-to-next-view-metric

detekt_custom.yml

@@ -1033,10 +1033,13 @@ datadog:
       - "kotlin.collections.MutableSet.firstOrNull(kotlin.Function1)"
       - "kotlin.collections.MutableSet.flatMap(kotlin.Function1)"
       - "kotlin.collections.MutableSet.forEach(kotlin.Function1)"
+      - "kotlin.collections.MutableSet.elementAtOrNull(kotlin.Int)"
+      - "kotlin.collections.MutableSet.indexOf(kotlin.String)"
       - "kotlin.collections.MutableSet.joinToString(kotlin.CharSequence, kotlin.CharSequence, kotlin.CharSequence, kotlin.Int, kotlin.CharSequence, kotlin.Function1?)"
       - "kotlin.collections.MutableSet.map(kotlin.Function1)"
       - "kotlin.collections.MutableSet.remove(com.datadog.android.core.internal.persistence.ConsentAwareStorage.Batch)"
       - "kotlin.collections.MutableSet.remove(java.io.File)"
+      - "kotlin.collections.MutableSet.remove(kotlin.collections.MutableMap.Mutab(...)"
       - "kotlin.collections.MutableSet.removeAll(kotlin.collections.Collection)"
       - "kotlin.collections.MutableSet.toList()"
       - "kotlin.collections.MutableSet.lastOrNull()"

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/domain/scope/RumViewManagerScope.kt

@@ -20,6 +20,7 @@ import com.datadog.android.rum.internal.domain.RumContext
 import com.datadog.android.rum.internal.domain.Time
 import com.datadog.android.rum.internal.metric.SessionEndedMetric
 import com.datadog.android.rum.internal.metric.SessionMetricDispatcher
+import com.datadog.android.rum.internal.metric.interactiontonextview.InteractionToNextViewMetricResolver
 import com.datadog.android.rum.internal.vitals.NoOpVitalMonitor
 import com.datadog.android.rum.internal.vitals.VitalMonitor
 import java.util.Locale
@@ -38,7 +39,9 @@ internal class RumViewManagerScope(
     private val memoryVitalMonitor: VitalMonitor,
     private val frameRateVitalMonitor: VitalMonitor,
     internal var applicationDisplayed: Boolean,
-    internal val sampleRate: Float
+    internal val sampleRate: Float,
+    private val interactionToNextViewMetricResolver: InteractionToNextViewMetricResolver =
+        InteractionToNextViewMetricResolver(internalLogger = sdkCore.internalLogger)
 ) : RumScope {
 
     internal val childrenScopes = mutableListOf<RumScope>()
@@ -198,7 +201,8 @@ internal class RumViewManagerScope(
             memoryVitalMonitor,
             frameRateVitalMonitor,
             trackFrustrations,
-            sampleRate
+            sampleRate,
+            interactionToNextViewMetricResolver
         )
         applicationDisplayed = true
         childrenScopes.add(viewScope)
@@ -260,7 +264,8 @@ internal class RumViewManagerScope(
             NoOpVitalMonitor(),
             type = RumViewScope.RumViewType.BACKGROUND,
             trackFrustrations = trackFrustrations,
-            sampleRate = sampleRate
+            sampleRate = sampleRate,
+            interactionToNextViewMetricResolver = interactionToNextViewMetricResolver
         )
     }
 
@@ -283,7 +288,8 @@ internal class RumViewManagerScope(
             NoOpVitalMonitor(),
             type = RumViewScope.RumViewType.APPLICATION_LAUNCH,
             trackFrustrations = trackFrustrations,
-            sampleRate = sampleRate
+            sampleRate = sampleRate,
+            interactionToNextViewMetricResolver = interactionToNextViewMetricResolver
         )
     }
 

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/domain/scope/RumViewScope.kt

@@ -25,6 +25,8 @@ import com.datadog.android.rum.internal.anr.ANRException
 import com.datadog.android.rum.internal.domain.RumContext
 import com.datadog.android.rum.internal.domain.Time
 import com.datadog.android.rum.internal.metric.SessionMetricDispatcher
+import com.datadog.android.rum.internal.metric.interactiontonextview.InteractionToNextViewMetricResolver
+import com.datadog.android.rum.internal.metric.interactiontonextview.InternalInteractionContext
 import com.datadog.android.rum.internal.metric.networksettled.NetworkSettledMetricResolver
 import com.datadog.android.rum.internal.monitor.StorageEvent
 import com.datadog.android.rum.internal.utils.hasUserData
@@ -59,6 +61,7 @@ internal open class RumViewScope(
     internal val type: RumViewType = RumViewType.FOREGROUND,
     private val trackFrustrations: Boolean,
     internal val sampleRate: Float,
+    private val interactionToNextViewMetricResolver: InteractionToNextViewMetricResolver,
     private val networkSettledMetricResolver: NetworkSettledMetricResolver =
         NetworkSettledMetricResolver(internalLogger = sdkCore.internalLogger)
 ) : RumScope {
@@ -162,6 +165,7 @@ internal open class RumViewScope(
             Log.i(RumScope.SYNTHETICS_LOGCAT_TAG, "_dd.view.id=$viewId")
         }
         networkSettledMetricResolver.viewWasCreated(eventTime.nanoTime)
+        interactionToNextViewMetricResolver.onViewCreated(viewId, eventTime.nanoTime)
     }
 
     // region RumScope
@@ -378,6 +382,14 @@ internal open class RumViewScope(
 
         if (stopped) return
 
+        interactionToNextViewMetricResolver.onActionSent(
+            InternalInteractionContext(
+                viewId,
+                event.type,
+                event.eventTime.nanoTime
+            )
+        )
+
         if (activeActionScope != null) {
             if (event.type == RumActionType.CUSTOM && !event.waitForStop) {
                 // deliver it anyway, even if there is active action ongoing
@@ -818,6 +830,7 @@ internal open class RumViewScope(
     private fun sendViewUpdate(event: RumRawEvent, writer: DataWriter<Any>, eventType: EventType = EventType.DEFAULT) {
         val viewComplete = isViewComplete()
         val timeToSettled = networkSettledMetricResolver.resolveMetric()
+        val interactionToNextViewTime = interactionToNextViewMetricResolver.resolveMetric(viewId)
         version++
 
         // make a local copy, so that closure captures the state as of now
@@ -916,6 +929,7 @@ internal open class RumViewScope(
                     flutterRasterTime = eventFlutterRasterTime,
                     jsRefreshRate = eventJsRefreshRate,
                     networkSettledTime = timeToSettled,
+                    interactionToNextViewTime = interactionToNextViewTime,
                     loadingTime = viewLoadingTime
                 ),
                 usr = if (user.hasUserData()) {
@@ -1335,7 +1349,8 @@ internal open class RumViewScope(
             memoryVitalMonitor: VitalMonitor,
             frameRateVitalMonitor: VitalMonitor,
             trackFrustrations: Boolean,
-            sampleRate: Float
+            sampleRate: Float,
+            interactionToNextViewMetricResolver: InteractionToNextViewMetricResolver
         ): RumViewScope {
             return RumViewScope(
                 parentScope,
@@ -1350,7 +1365,8 @@ internal open class RumViewScope(
                 memoryVitalMonitor,
                 frameRateVitalMonitor,
                 trackFrustrations = trackFrustrations,
-                sampleRate = sampleRate
+                sampleRate = sampleRate,
+                interactionToNextViewMetricResolver = interactionToNextViewMetricResolver
             )
         }
 

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/metric/interactiontonextview/ActionTypeInteractionValidator.kt

@@ -0,0 +1,26 @@
+/*
+ * Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
+ * This product includes software developed at Datadog (https://www.datadoghq.com/).
+ * Copyright 2016-Present Datadog, Inc.
+ */
+
+package com.datadog.android.rum.internal.metric.interactiontonextview
+
+import com.datadog.android.rum.RumActionType
+
+internal class ActionTypeInteractionValidator : InteractionIngestionValidator {
+    override fun validate(
+        context: InternalInteractionContext
+    ): Boolean {
+        return context.actionType in ALLOWED_TYPES
+    }
+
+    companion object {
+        private val ALLOWED_TYPES = setOf(
+            RumActionType.TAP,
+            RumActionType.SWIPE,
+            RumActionType.CLICK,
+            RumActionType.BACK
+        )
+    }
+}

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/metric/interactiontonextview/InteractionIngestionValidator.kt

@@ -0,0 +1,13 @@
+/*
+ * Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
+ * This product includes software developed at Datadog (https://www.datadoghq.com/).
+ * Copyright 2016-Present Datadog, Inc.
+ */
+
+package com.datadog.android.rum.internal.metric.interactiontonextview
+
+internal interface InteractionIngestionValidator {
+    fun validate(
+        context: InternalInteractionContext
+    ): Boolean
+}

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/metric/interactiontonextview/InteractionToNextViewMetricResolver.kt

@@ -0,0 +1,120 @@
+/*
+ * Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
+ * This product includes software developed at Datadog (https://www.datadoghq.com/).
+ * Copyright 2016-Present Datadog, Inc.
+ */
+
+package com.datadog.android.rum.internal.metric.interactiontonextview
+
+import androidx.annotation.VisibleForTesting
+import com.datadog.android.api.InternalLogger
+
+internal class InteractionToNextViewMetricResolver(
+    private val internalLogger: InternalLogger,
+    private val ingestionValidator: InteractionIngestionValidator = ActionTypeInteractionValidator(),
+    private val lastInteractionIdentifier: LastInteractionIdentifier = TimeBasedInteractionIdentifier()
+) {
+
+    private val lastInteractions = LinkedHashMap<String, InternalInteractionContext>()
+    private val lastViewCreatedTimestamps = LinkedHashMap<String, Long>()
+
+    fun onViewCreated(viewId: String, timestamp: Long) {
+        lastViewCreatedTimestamps[viewId] = timestamp
+        purgeOldEntries()
+    }
+
+    fun onActionSent(context: InternalInteractionContext) {
+        if (ingestionValidator.validate(context)) {
+            lastInteractions[context.viewId] = context
+        }
+        purgeOldEntries()
+    }
+
+    @Suppress("ReturnCount")
+    fun resolveMetric(viewId: String): Long? {
+        purgeOldEntries()
+        val currentViewCreatedTimestamp = lastViewCreatedTimestamps[viewId]
+        if (currentViewCreatedTimestamp == null) {
+            internalLogger.log(
+                InternalLogger.Level.WARN,
+                InternalLogger.Target.MAINTAINER,
+                { "[ViewNetworkSettledMetric] The view was not yet created for this viewId:$viewId" }
+            )
+            return null
+        }
+        val lastPrevViewInteraction = resolveLastInteraction(viewId, currentViewCreatedTimestamp)
+        if (lastPrevViewInteraction != null) {
+            val difference = currentViewCreatedTimestamp - lastPrevViewInteraction.eventCreatedAtNanos
+            if (difference > 0) {
+                return difference
+            } else {
+                internalLogger.log(
+                    InternalLogger.Level.WARN,
+                    InternalLogger.Target.MAINTAINER,
+                    {
+                        "[ViewNetworkSettledMetric] The difference between the last interaction " +
+                            "and the current view is negative for viewId:$viewId"
+                    }
+                )
+                return null
+            }
+        }
+        // in case there are no previous interactions for this view and there's only one view created
+        // we are probably in the first view of the app (AppLaunch) and we can't calculate the metric
+        if (lastViewCreatedTimestamps.size > 1) {
+            internalLogger.log(
+                InternalLogger.Level.WARN,
+                InternalLogger.Target.MAINTAINER,
+                { "[ViewNetworkSettledMetric] No previous interaction found for this viewId:$viewId" }
+            )
+        }
+        return null
+    }
+
+    private fun resolveLastInteraction(viewId: String, currentViewCreatedTimestamp: Long): InternalInteractionContext? {
+        val currentViewIdIndex = lastViewCreatedTimestamps.keys.indexOf(viewId)
+        val previousViewId = lastViewCreatedTimestamps.keys.elementAtOrNull(currentViewIdIndex - 1)
+        if (previousViewId != null) {
+            lastInteractions[previousViewId]?.let {
+                val context = PreviousViewLastInteractionContext(
+                    it.actionType,
+                    it.eventCreatedAtNanos,
+                    currentViewCreatedTimestamp
+                )
+                if (lastInteractionIdentifier.validate(context)) {
+                    return it
+                }
+            }
+        }
+        return null
+    }
+
+    private fun purgeOldEntries() {
+        while (lastInteractions.entries.size > MAX_ENTRIES) {
+            @Suppress("UnsafeThirdPartyFunctionCall")
+            // we make sure the collection is never empty
+            lastInteractions.entries.remove(lastInteractions.entries.first())
+        }
+        while (lastViewCreatedTimestamps.entries.size > MAX_ENTRIES) {
+            @Suppress("UnsafeThirdPartyFunctionCall")
+            // we make sure the collection is never empty
+            lastViewCreatedTimestamps.remove(lastViewCreatedTimestamps.keys.first())
+        }
+    }
+
+    @VisibleForTesting
+    internal fun lasInteractions(): Map<String, InternalInteractionContext> {
+        return lastInteractions
+    }
+
+    @VisibleForTesting
+    internal fun lastViewCreatedTimestamps(): Map<String, Long> {
+        return lastViewCreatedTimestamps
+    }
+
+    companion object {
+        // we need to keep at least 4 entries to be able to calculate the metric for consecutive views that
+        // are going to be created almost in the same time and will rely on the previous view interaction
+        internal const val MAX_ENTRIES = 4
+    }
+}

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/metric/interactiontonextview/InternalInteractionContext.kt

@@ -0,0 +1,15 @@
+/*
+ * Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
+ * This product includes software developed at Datadog (https://www.datadoghq.com/).
+ * Copyright 2016-Present Datadog, Inc.
+ */
+
+package com.datadog.android.rum.internal.metric.interactiontonextview
+
+import com.datadog.android.rum.RumActionType
+
+internal data class InternalInteractionContext(
+    internal val viewId: String,
+    internal val actionType: RumActionType,
+    internal val eventCreatedAtNanos: Long
+)

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/metric/interactiontonextview/LastInteractionIdentifier.kt

@@ -0,0 +1,11 @@
+/*
+ * Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
+ * This product includes software developed at Datadog (https://www.datadoghq.com/).
+ * Copyright 2016-Present Datadog, Inc.
+ */
+
+package com.datadog.android.rum.internal.metric.interactiontonextview
+
+internal interface LastInteractionIdentifier {
+    fun validate(context: PreviousViewLastInteractionContext): Boolean
+}

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/metric/interactiontonextview/PreviousViewLastInteractionContext.kt

@@ -0,0 +1,15 @@
+/*
+ * Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
+ * This product includes software developed at Datadog (https://www.datadoghq.com/).
+ * Copyright 2016-Present Datadog, Inc.
+ */
+
+package com.datadog.android.rum.internal.metric.interactiontonextview
+
+import com.datadog.android.rum.RumActionType
+
+internal data class PreviousViewLastInteractionContext(
+    internal val actionType: RumActionType,
+    internal val eventCreatedAtNanos: Long,
+    internal val currentViewCreationTimestamp: Long?
+)

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/metric/interactiontonextview/TimeBasedInteractionIdentifier.kt

@@ -0,0 +1,24 @@
+/*
+ * Unless explicitly stated otherwise all files in this repository are licensed under the Apache License Version 2.0.
+ * This product includes software developed at Datadog (https://www.datadoghq.com/).
+ * Copyright 2016-Present Datadog, Inc.
+ */
+
+package com.datadog.android.rum.internal.metric.interactiontonextview
+
+import java.util.concurrent.TimeUnit
+
+internal class TimeBasedInteractionIdentifier(
+    private val timeThresholdInNanoSeconds: Long = TimeUnit.MILLISECONDS.toNanos(DEFAULT_TIME_THRESHOLD_MS)
+) : LastInteractionIdentifier {
+
+    override fun validate(context: PreviousViewLastInteractionContext): Boolean {
+        return context.currentViewCreationTimestamp?.let { viewCreatedTime ->
+            context.eventCreatedAtNanos - viewCreatedTime < timeThresholdInNanoSeconds
+        } ?: false
+    }
+
+    companion object {
+        internal const val DEFAULT_TIME_THRESHOLD_MS = 3000L
+    }
+}

features/dd-sdk-android-rum/src/test/kotlin/com/datadog/android/rum/assertj/ViewEventAssert.kt

@@ -266,6 +266,18 @@ internal class ViewEventAssert(actual: ViewEvent) :
         return this
     }
 
+    fun hasInteractionToNextViewTime(
+        expected: Long?
+    ): ViewEventAssert {
+        assertThat(actual.view.interactionToNextViewTime)
+            .overridingErrorMessage(
+                "Expected event to have interactionToNextViewTime $expected" +
+                    " but was ${actual.view.interactionToNextViewTime}"
+            )
+            .isEqualTo(expected)
+        return this
+    }
+
     fun hasLoadingType(
         expected: ViewEvent.LoadingType?
     ): ViewEventAssert {

features/dd-sdk-android-rum/src/test/kotlin/com/datadog/android/rum/internal/domain/scope/RumSessionScopeTest.kt

@@ -119,6 +119,7 @@ internal class RumSessionScopeTest {
         whenever(mockSdkCore.getFeature(Feature.SESSION_REPLAY_FEATURE_NAME)) doReturn
             mockSessionReplayFeatureScope
         whenever(mockSdkCore.time) doReturn (fakeTimeInfo)
+        whenever(mockSdkCore.internalLogger) doReturn mock()
 
         initializeTestedScope()
     }