Refactor jank to use events

android-agent/src/main/kotlin/io/opentelemetry/android/agent/OpenTelemetryRumInitializer.kt

@@ -180,9 +180,9 @@ object OpenTelemetryRumInitializer {
         }
 
         if (slowRenderingDetectionPollInterval != null) {
-            getInstrumentation<SlowRenderingInstrumentation>()?.setSlowRenderingDetectionPollInterval(
-                slowRenderingDetectionPollInterval,
-            )
+            val instrumentation = getInstrumentation<SlowRenderingInstrumentation>()
+            instrumentation?.setSlowRenderingDetectionPollInterval(slowRenderingDetectionPollInterval)
+            instrumentation?.enableDeprecatedZeroDurationSpan()
         }
     }
 

instrumentation/slowrendering/api/slowrendering.api

@@ -1,5 +1,6 @@
 public final class io/opentelemetry/android/instrumentation/slowrendering/SlowRenderingInstrumentation : io/opentelemetry/android/instrumentation/AndroidInstrumentation {
 	public fun <init> ()V
+	public final fun enableDeprecatedZeroDurationSpan ()Lio/opentelemetry/android/instrumentation/slowrendering/SlowRenderingInstrumentation;
 	public fun getName ()Ljava/lang/String;
 	public fun install (Lio/opentelemetry/android/instrumentation/InstallationContext;)V
 	public final fun setSlowRenderingDetectionPollInterval (Ljava/time/Duration;)Lio/opentelemetry/android/instrumentation/slowrendering/SlowRenderingInstrumentation;

instrumentation/slowrendering/build.gradle.kts

@@ -11,6 +11,10 @@ android {
     defaultConfig {
         consumerProguardFiles("consumer-rules.pro")
     }
+
+    testOptions {
+        unitTests.isReturnDefaultValues = true
+    }
 }
 
 dependencies {
@@ -24,5 +28,6 @@ dependencies {
     implementation(libs.opentelemetry.semconv)
     implementation(libs.opentelemetry.sdk)
     implementation(libs.opentelemetry.instrumentation.api)
+    implementation(libs.opentelemetry.sdk.extension.incubator)
     testImplementation(libs.robolectric)
 }

instrumentation/slowrendering/config/detekt/baseline.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" ?>
+<SmellBaseline>
+  <ManuallySuppressedIssues/>
+  <CurrentIssues>
+    <ID>EmptyFunctionBlock:JankReporterTest.kt$JankReporterTest.&lt;no name provided&gt;${ }</ID>
+    <ID>ForbiddenComment:EventsJankReporter.kt$// TODO: Replace with semconv constants</ID>
+    <ID>MagicNumber:EventsJankReporter.kt$EventsJankReporter$1000.0</ID>
+    <ID>MagicNumber:SlowRenderingInstrumentation.kt$SlowRenderingInstrumentation$1000.0</ID>
+    <ID>TooGenericExceptionCaught:SlowRenderListener.kt$SlowRenderListener$e: Exception</ID>
+  </CurrentIssues>
+</SmellBaseline>

instrumentation/slowrendering/src/main/java/io/opentelemetry/android/instrumentation/slowrendering/EventsJankReporter.kt

@@ -0,0 +1,58 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.android.instrumentation.slowrendering
+
+import android.util.Log
+import android.util.SparseIntArray
+import io.opentelemetry.android.common.RumConstants
+import io.opentelemetry.api.common.AttributeKey
+import io.opentelemetry.api.common.Attributes
+import io.opentelemetry.api.incubator.logs.ExtendedLogRecordBuilder
+import io.opentelemetry.api.logs.Logger
+
+// TODO: Replace with semconv constants
+internal val FRAME_COUNT: AttributeKey<Long> = AttributeKey.longKey("app.jank.frame_count")
+internal val PERIOD: AttributeKey<Double> = AttributeKey.doubleKey("app.jank.period")
+internal val THRESHOLD: AttributeKey<Double> = AttributeKey.doubleKey("app.jank.threshold")
+
+internal class EventsJankReporter(
+    private val eventLogger: Logger,
+    private val threshold: Double,
+) : JankReporter {
+    override fun reportSlow(
+        durationToCountHistogram: SparseIntArray,
+        periodSeconds: Double,
+        activityName: String,
+    ) {
+        var frameCount: Long = 0
+        for (i in 0 until durationToCountHistogram.size()) {
+            val durationMillis = durationToCountHistogram.keyAt(i)
+            if ((durationMillis / 1000.0) > threshold) {
+                val count = durationToCountHistogram.get(durationMillis)
+                Log.d(
+                    RumConstants.OTEL_RUM_LOG_TAG,
+                    "* Slow render detected: $durationMillis ms. $count times",
+                )
+                frameCount += count
+            }
+        }
+
+        if (frameCount > 0) {
+            val eventBuilder = eventLogger.logRecordBuilder() as ExtendedLogRecordBuilder
+            val attributes =
+                Attributes
+                    .builder()
+                    .put(FRAME_COUNT, frameCount)
+                    .put(PERIOD, periodSeconds)
+                    .put(THRESHOLD, threshold)
+                    .build()
+            eventBuilder
+                .setEventName("app.jank")
+                .setAllAttributes(attributes)
+                .emit()
+        }
+    }
+}

instrumentation/slowrendering/src/main/java/io/opentelemetry/android/instrumentation/slowrendering/JankReporter.kt

@@ -0,0 +1,39 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.android.instrumentation.slowrendering
+
+import android.util.SparseIntArray
+
+/**
+ * Responsible for sending telemetry. This is a temporary class that we can remove
+ * after the jank semconv becomes more stable.
+ */
+internal fun interface JankReporter {
+    fun reportSlow(
+        durationToCountHistogram: SparseIntArray,
+        periodSeconds: Double,
+        activityName: String,
+    )
+
+    /**
+     * Creates a combined JankReporter that will first report slow for this
+     * instance and then delegate to another JankReporter instance.
+     */
+    fun combine(jankReporter: JankReporter): JankReporter {
+        require(jankReporter != this) { "cannot combine with self" }
+        val exec = this::reportSlow
+        return object : JankReporter {
+            override fun reportSlow(
+                durationToCountHistogram: SparseIntArray,
+                periodSeconds: Double,
+                activityName: String,
+            ) {
+                exec(durationToCountHistogram, periodSeconds, activityName)
+                jankReporter.reportSlow(durationToCountHistogram, periodSeconds, activityName)
+            }
+        }
+    }
+}

instrumentation/slowrendering/src/main/java/io/opentelemetry/android/instrumentation/slowrendering/PerActivityListener.kt

@@ -0,0 +1,63 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.android.instrumentation.slowrendering
+
+import android.app.Activity
+import android.os.Build
+import android.util.SparseIntArray
+import android.view.FrameMetrics
+import android.view.Window
+import android.view.Window.OnFrameMetricsAvailableListener
+import androidx.annotation.GuardedBy
+import androidx.annotation.RequiresApi
+import java.util.concurrent.TimeUnit
+
+private val NANOS_PER_MS = TimeUnit.MILLISECONDS.toNanos(1).toInt()
+
+// rounding value adds half a millisecond, for rounding to nearest ms
+private val NANOS_ROUNDING_VALUE: Int = NANOS_PER_MS / 2
+
+@RequiresApi(api = Build.VERSION_CODES.N)
+internal class PerActivityListener(
+    private val activity: Activity,
+) : OnFrameMetricsAvailableListener {
+    private val lock = Any()
+
+    @GuardedBy("lock")
+    private var drawDurationHistogram = SparseIntArray()
+
+    fun getActivityName(): String = activity.componentName.flattenToShortString()
+
+    override fun onFrameMetricsAvailable(
+        window: Window?,
+        frameMetrics: FrameMetrics,
+        dropCountSinceLastInvocation: Int,
+    ) {
+        val firstDrawFrame = frameMetrics.getMetric(FrameMetrics.FIRST_DRAW_FRAME)
+        if (firstDrawFrame == 1L) {
+            return
+        }
+
+        val drawDurationsNs = frameMetrics.getMetric(FrameMetrics.DRAW_DURATION)
+        // ignore values < 0; something must have gone wrong
+        if (drawDurationsNs >= 0) {
+            synchronized(lock) {
+                // calculation copied from FrameMetricsAggregator
+                val durationMs = ((drawDurationsNs + NANOS_ROUNDING_VALUE) / NANOS_PER_MS).toInt()
+                val oldValue = drawDurationHistogram.get(durationMs)
+                drawDurationHistogram.put(durationMs, (oldValue + 1))
+            }
+        }
+    }
+
+    fun resetMetrics(): SparseIntArray {
+        synchronized(lock) {
+            val metrics = drawDurationHistogram
+            drawDurationHistogram = SparseIntArray()
+            return metrics
+        }
+    }
+}