Add framework event infra

Summary:
Added infra for collecting events from UI frameworks.
1. Framework event metadata captures all the static metadata around the event. This allows to us to not send the same metadata in every event as well as populate the monitoring drop down immediately. This is sent in init since this information is static
2. Framework event itself is quite bare at the moment. It will have thread and more attributes in the future

The UIdebugger litho support ulitity has been simplified now there are 3 extension points.

Context renamed to UIDContext since it is referenced in app initialisers where the android context is also imported and it create a naming collision

Reviewed By: lblasa

Differential Revision: D42606933

fbshipit-source-id: a419f3fd424c533d586813004c40b68feafd9a2e

android/plugins/litho/src/main/java/com/facebook/flipper/plugins/uidebugger/litho/UIDebuggerLithoSupportStub.kt

@@ -7,13 +7,10 @@
 
 package com.facebook.flipper.plugins.uidebugger.litho
 
-import com.facebook.flipper.plugins.uidebugger.descriptors.DescriptorRegister
-import com.facebook.flipper.plugins.uidebugger.observers.TreeObserverFactory
+import com.facebook.flipper.plugins.uidebugger.core.UIDContext
 
 // this is not used internally
 object UIDebuggerLithoSupport {
 
-  fun addDescriptors(register: DescriptorRegister) {}
-
-  fun addObserver(observerFactory: TreeObserverFactory) {}
+  fun enable(context: UIDContext) {}
 }

android/sample/src/debug/java/com/facebook/flipper/sample/FlipperInitializer.java

@@ -22,6 +22,7 @@
 import com.facebook.flipper.plugins.sharedpreferences.SharedPreferencesFlipperPlugin;
 import com.facebook.flipper.plugins.sharedpreferences.SharedPreferencesFlipperPlugin.SharedPreferencesDescriptor;
 import com.facebook.flipper.plugins.uidebugger.UIDebuggerFlipperPlugin;
+import com.facebook.flipper.plugins.uidebugger.core.UIDContext;
 import com.facebook.flipper.plugins.uidebugger.descriptors.DescriptorRegister;
 import com.facebook.flipper.plugins.uidebugger.litho.UIDebuggerLithoSupport;
 import com.facebook.flipper.plugins.uidebugger.observers.TreeObserverFactory;
@@ -62,12 +63,10 @@ public static InitializationResult initFlipperPlugins(Context context, FlipperCl
 
     DescriptorRegister descriptorRegister = DescriptorRegister.Companion.withDefaults();
     TreeObserverFactory treeObserverFactory = TreeObserverFactory.Companion.withDefaults();
-    UIDebuggerLithoSupport.INSTANCE.addDescriptors(descriptorRegister);
-    UIDebuggerLithoSupport.INSTANCE.addObserver(treeObserverFactory);
+    UIDContext uidContext = UIDContext.Companion.create((Application) context);
+    UIDebuggerLithoSupport.INSTANCE.enable(uidContext);
 
-    client.addPlugin(
-        new UIDebuggerFlipperPlugin(
-            (Application) context, descriptorRegister, treeObserverFactory));
+    client.addPlugin(new UIDebuggerFlipperPlugin(uidContext));
     client.start();
 
     final OkHttpClient okHttpClient =

android/src/main/java/com/facebook/flipper/plugins/uidebugger/UIDebuggerFlipperPlugin.kt

@@ -7,33 +7,19 @@
 
 package com.facebook.flipper.plugins.uidebugger
 
-import android.app.Application
 import android.util.Log
 import com.facebook.flipper.core.FlipperConnection
 import com.facebook.flipper.core.FlipperPlugin
 import com.facebook.flipper.plugins.uidebugger.core.*
 import com.facebook.flipper.plugins.uidebugger.descriptors.ApplicationRefDescriptor
-import com.facebook.flipper.plugins.uidebugger.descriptors.DescriptorRegister
 import com.facebook.flipper.plugins.uidebugger.descriptors.MetadataRegister
 import com.facebook.flipper.plugins.uidebugger.model.InitEvent
 import com.facebook.flipper.plugins.uidebugger.model.MetadataUpdateEvent
-import com.facebook.flipper.plugins.uidebugger.observers.TreeObserverFactory
 import kotlinx.serialization.json.Json
 
 const val LogTag = "ui-debugger"
 
-class UIDebuggerFlipperPlugin(
-    val application: Application,
-    descriptorRegister: DescriptorRegister?,
-    observerFactory: TreeObserverFactory?
-) : FlipperPlugin {
-
-  private val context: Context =
-      Context(
-          ApplicationRef(application),
-          ConnectionRef(null),
-          descriptorRegister = descriptorRegister ?: DescriptorRegister.withDefaults(),
-          observerFactory = observerFactory ?: TreeObserverFactory.withDefaults())
+class UIDebuggerFlipperPlugin(val context: UIDContext) : FlipperPlugin {
 
   init {
     Log.i(LogTag, "Initializing ui-debugger")
@@ -53,7 +39,9 @@ class UIDebuggerFlipperPlugin(
         InitEvent.name,
         Json.encodeToString(
             InitEvent.serializer(),
-            InitEvent(ApplicationRefDescriptor.getId(context.applicationRef))))
+            InitEvent(
+                ApplicationRefDescriptor.getId(context.applicationRef),
+                context.frameworkEventMetadata)))
 
     connection.send(
         MetadataUpdateEvent.name,

android/src/main/java/com/facebook/flipper/plugins/uidebugger/commands/Command.kt

@@ -11,10 +11,10 @@ import com.facebook.flipper.core.FlipperObject
 import com.facebook.flipper.core.FlipperReceiver
 import com.facebook.flipper.core.FlipperResponder
 import com.facebook.flipper.plugins.common.MainThreadFlipperReceiver
-import com.facebook.flipper.plugins.uidebugger.core.Context
+import com.facebook.flipper.plugins.uidebugger.core.UIDContext
 
 /** An interface for extensions to the UIDebugger plugin */
-abstract class Command(val context: Context) {
+abstract class Command(val context: UIDContext) {
   /** The command identifier to respond to */
   abstract fun identifier(): String
   /** Execute the command */

android/src/main/java/com/facebook/flipper/plugins/uidebugger/core/Context.kt → android/src/main/java/com/facebook/flipper/plugins/uidebugger/core/UIDContext.kt

@@ -7,26 +7,40 @@
 
 package com.facebook.flipper.plugins.uidebugger.core
 
+import android.app.Application
 import com.facebook.flipper.core.FlipperConnection
 import com.facebook.flipper.plugins.uidebugger.common.BitmapPool
 import com.facebook.flipper.plugins.uidebugger.descriptors.DescriptorRegister
+import com.facebook.flipper.plugins.uidebugger.model.FrameworkEventMetadata
 import com.facebook.flipper.plugins.uidebugger.observers.TreeObserverFactory
 import com.facebook.flipper.plugins.uidebugger.observers.TreeObserverManager
 import com.facebook.flipper.plugins.uidebugger.scheduler.SharedThrottle
 import com.facebook.flipper.plugins.uidebugger.traversal.PartialLayoutTraversal
 
-data class Context(
+data class UIDContext(
     val applicationRef: ApplicationRef,
     val connectionRef: ConnectionRef,
     val descriptorRegister: DescriptorRegister,
     val observerFactory: TreeObserverFactory,
+    val frameworkEventMetadata: MutableList<FrameworkEventMetadata>
 ) {
   val layoutTraversal: PartialLayoutTraversal =
       PartialLayoutTraversal(descriptorRegister, observerFactory)
 
   val treeObserverManager = TreeObserverManager(this)
   val sharedThrottle: SharedThrottle = SharedThrottle()
   val bitmapPool = BitmapPool()
+
+  companion object {
+    fun create(application: Application): UIDContext {
+      return UIDContext(
+          ApplicationRef(application),
+          ConnectionRef(null),
+          descriptorRegister = DescriptorRegister.withDefaults(),
+          observerFactory = TreeObserverFactory.withDefaults(),
+          frameworkEventMetadata = mutableListOf())
+    }
+  }
 }
 
 data class ConnectionRef(var connection: FlipperConnection?)

android/src/main/java/com/facebook/flipper/plugins/uidebugger/model/Events.kt

@@ -10,9 +10,7 @@ package com.facebook.flipper.plugins.uidebugger.model
 import com.facebook.flipper.plugins.uidebugger.descriptors.Id
 
 @kotlinx.serialization.Serializable
-data class InitEvent(
-    val rootId: Id,
-) {
+data class InitEvent(val rootId: Id, val frameworkEventMetadata: List<FrameworkEventMetadata>) {
   companion object {
     const val name = "init"
   }
@@ -31,7 +29,8 @@ data class SubtreeUpdateEvent(
     val observerType: String,
     val rootId: Id,
     val nodes: List<Node>,
-    val snapshot: String? = null
+    val snapshot: String?,
+    val frameworkEvents: List<FrameworkEvent>?
 ) {
   companion object {
     const val name = "subtreeUpdate"

android/src/main/java/com/facebook/flipper/plugins/uidebugger/model/FrameworkEvents.kt

@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package com.facebook.flipper.plugins.uidebugger.model
+
+import com.facebook.flipper.plugins.uidebugger.descriptors.Id
+
+@kotlinx.serialization.Serializable
+data class FrameworkEventMetadata(
+    val type: String,
+    val documentation: String,
+)
+
+@kotlinx.serialization.Serializable
+data class FrameworkEvent(
+    val nodeId: Id,
+    val type: String,
+    val timestamp: Long,
+)

android/src/main/java/com/facebook/flipper/plugins/uidebugger/observers/ApplicationTreeObserver.kt

@@ -11,15 +11,15 @@ import android.util.Log
 import android.view.View
 import com.facebook.flipper.plugins.uidebugger.LogTag
 import com.facebook.flipper.plugins.uidebugger.core.ApplicationRef
-import com.facebook.flipper.plugins.uidebugger.core.Context
 import com.facebook.flipper.plugins.uidebugger.core.RootViewResolver
+import com.facebook.flipper.plugins.uidebugger.core.UIDContext
 import com.facebook.flipper.plugins.uidebugger.util.objectIdentity
 
 /**
  * Responsible for observing the activity stack and managing the subscription to the top most
  * content view (decor view)
  */
-class ApplicationTreeObserver(val context: Context) : TreeObserver<ApplicationRef>() {
+class ApplicationTreeObserver(val context: UIDContext) : TreeObserver<ApplicationRef>() {
 
   override val type = "Application"
 

android/src/main/java/com/facebook/flipper/plugins/uidebugger/observers/DecorViewTreeObserver.kt

@@ -12,14 +12,14 @@ import android.view.View
 import android.view.ViewTreeObserver
 import com.facebook.flipper.plugins.uidebugger.LogTag
 import com.facebook.flipper.plugins.uidebugger.common.BitmapPool
-import com.facebook.flipper.plugins.uidebugger.core.Context
+import com.facebook.flipper.plugins.uidebugger.core.UIDContext
 import com.facebook.flipper.plugins.uidebugger.util.objectIdentity
 import java.lang.ref.WeakReference
 
 typealias DecorView = View
 
 /** Responsible for subscribing to updates to the content view of an activity */
-class DecorViewObserver(val context: Context) : TreeObserver<DecorView>() {
+class DecorViewObserver(val context: UIDContext) : TreeObserver<DecorView>() {
 
   private var nodeRef: WeakReference<View>? = null
   private var preDrawListener: ViewTreeObserver.OnPreDrawListener? = null
@@ -78,7 +78,7 @@ object DecorViewTreeObserverBuilder : TreeObserverBuilder<DecorView> {
     return node.javaClass.simpleName.contains("DecorView")
   }
 
-  override fun build(context: Context): TreeObserver<DecorView> {
+  override fun build(context: UIDContext): TreeObserver<DecorView> {
     Log.i(LogTag, "Building DecorView observer")
     return DecorViewObserver(context)
   }

android/src/main/java/com/facebook/flipper/plugins/uidebugger/observers/TreeObserver.kt

@@ -10,9 +10,10 @@ package com.facebook.flipper.plugins.uidebugger.observers
 import android.util.Log
 import com.facebook.flipper.plugins.uidebugger.LogTag
 import com.facebook.flipper.plugins.uidebugger.common.BitmapPool
-import com.facebook.flipper.plugins.uidebugger.core.Context
+import com.facebook.flipper.plugins.uidebugger.core.UIDContext
 import com.facebook.flipper.plugins.uidebugger.descriptors.Id
 import com.facebook.flipper.plugins.uidebugger.descriptors.NodeDescriptor
+import com.facebook.flipper.plugins.uidebugger.model.FrameworkEvent
 import com.facebook.flipper.plugins.uidebugger.util.objectIdentity
 
 /*
@@ -40,9 +41,10 @@ abstract class TreeObserver<T> {
 
   /** Traverses the layout hierarchy while managing any encountered child observers. */
   fun traverseAndSend(
-      context: Context,
+      context: UIDContext,
       root: Any,
-      snapshotBitmap: BitmapPool.ReusableBitmap? = null
+      snapshotBitmap: BitmapPool.ReusableBitmap? = null,
+      frameworkEvents: List<FrameworkEvent>? = null
   ) {
     val startTimestamp = System.currentTimeMillis()
     val (visitedNodes, observableRoots) = context.layoutTraversal.traverse(root)
@@ -97,6 +99,7 @@ abstract class TreeObserver<T> {
             startTimestamp,
             traversalCompleteTime,
             snapshotCompleteTime,
+            frameworkEvents,
             snapshotBitmap))
   }
 

android/src/main/java/com/facebook/flipper/plugins/uidebugger/observers/TreeObserverFactory.kt

@@ -7,11 +7,11 @@
 
 package com.facebook.flipper.plugins.uidebugger.observers
 
-import com.facebook.flipper.plugins.uidebugger.core.Context
+import com.facebook.flipper.plugins.uidebugger.core.UIDContext
 
 interface TreeObserverBuilder<T> {
   fun canBuildFor(node: Any): Boolean
-  fun build(context: Context): TreeObserver<T>
+  fun build(context: UIDContext): TreeObserver<T>
 }
 
 class TreeObserverFactory {
@@ -28,7 +28,7 @@ class TreeObserverFactory {
   }
 
   // TODO: Not very efficient, need to cache this. Builders cannot be removed.
-  fun createObserver(node: Any, context: Context): TreeObserver<*>? {
+  fun createObserver(node: Any, context: UIDContext): TreeObserver<*>? {
     return builders.find { it.canBuildFor(node) }?.build(context)
   }
 

android/src/main/java/com/facebook/flipper/plugins/uidebugger/observers/TreeObserverManager.kt

@@ -16,9 +16,10 @@ import android.util.Log
 import android.view.Choreographer
 import com.facebook.flipper.plugins.uidebugger.LogTag
 import com.facebook.flipper.plugins.uidebugger.common.BitmapPool
-import com.facebook.flipper.plugins.uidebugger.core.Context
+import com.facebook.flipper.plugins.uidebugger.core.UIDContext
 import com.facebook.flipper.plugins.uidebugger.descriptors.Id
 import com.facebook.flipper.plugins.uidebugger.descriptors.MetadataRegister
+import com.facebook.flipper.plugins.uidebugger.model.FrameworkEvent
 import com.facebook.flipper.plugins.uidebugger.model.MetadataUpdateEvent
 import com.facebook.flipper.plugins.uidebugger.model.Node
 import com.facebook.flipper.plugins.uidebugger.model.PerfStatsEvent
@@ -37,13 +38,14 @@ data class SubtreeUpdate(
     val startTime: Long,
     val traversalCompleteTime: Long,
     val snapshotComplete: Long,
+    val frameworkEvents: List<FrameworkEvent>?,
     val snapshot: BitmapPool.ReusableBitmap?
 )
 
 data class BatchedUpdate(val updates: List<SubtreeUpdate>, val frameTimeMs: Long)
 
 /** Holds the root observer and manages sending updates to desktop */
-class TreeObserverManager(val context: Context) {
+class TreeObserverManager(val context: UIDContext) {
 
   private val rootObserver = ApplicationTreeObserver(context)
   private lateinit var batchedUpdates: Channel<BatchedUpdate>
@@ -104,6 +106,7 @@ class TreeObserverManager(val context: Context) {
     val onWorkerThread = System.currentTimeMillis()
 
     val nodes = batchedUpdate.updates.flatMap { it.deferredNodes.map { it.value() } }
+    val frameworkEvents = batchedUpdate.updates.flatMap { it.frameworkEvents ?: listOf() }
     val snapshotUpdate = batchedUpdate.updates.find { it.snapshot != null }
     val deferredComptationComplete = System.currentTimeMillis()
 
@@ -116,13 +119,20 @@ class TreeObserverManager(val context: Context) {
       snapshotUpdate.snapshot.readyForReuse()
     }
 
+    // it is important this comes after deferred processing since the deferred processing can create
+    // metadata
     sendMetadata()
 
     val serialized =
         Json.encodeToString(
             SubtreeUpdateEvent.serializer(),
             SubtreeUpdateEvent(
-                batchedUpdate.frameTimeMs, "batched", snapshotUpdate?.rootId ?: 1, nodes, snapshot))
+                batchedUpdate.frameTimeMs,
+                "batched",
+                snapshotUpdate?.rootId ?: 1,
+                nodes,
+                snapshot,
+                frameworkEvents))
 
     val serializationEnd = System.currentTimeMillis()
 

android/src/test/java/com/facebook/flipper/plugins/uidebugger/UIDebuggerFlipperPluginTest.kt

@@ -8,8 +8,7 @@
 package com.facebook.flipper.plugins.uidebugger
 
 import com.facebook.flipper.plugins.uidebugger.core.ApplicationRef
-import com.facebook.flipper.plugins.uidebugger.descriptors.DescriptorRegister
-import com.facebook.flipper.plugins.uidebugger.observers.TreeObserverFactory
+import com.facebook.flipper.plugins.uidebugger.core.UIDContext
 import org.junit.Assert
 import org.junit.Before
 import org.junit.Test
@@ -32,11 +31,7 @@ class UIDebuggerFlipperPluginTest {
   @Throws(Exception::class)
   @Test
   fun emptyTest() {
-    var plugin =
-        UIDebuggerFlipperPlugin(
-            app,
-            DescriptorRegister.Companion.withDefaults(),
-            TreeObserverFactory.Companion.withDefaults())
+    var plugin = UIDebuggerFlipperPlugin(UIDContext.create(app))
     Assert.assertNotNull(plugin)
   }
 }