[analytics] introduces constants (#8601)

Follow-up from #8597. Introduces constants.

---

- [x] I’ve reviewed the contributor guide and applied the relevant
portions to this PR.

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  <summary>Contribution guidelines:</summary><br>

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Author: pq

src/io/flutter/actions/FlutterSdkAction.java

@@ -14,6 +14,7 @@
 import io.flutter.FlutterMessages;
 import io.flutter.FlutterUtils;
 import io.flutter.analytics.Analytics;
+import io.flutter.analytics.AnalyticsConstants;
 import io.flutter.analytics.AnalyticsData;
 import io.flutter.bazel.Workspace;
 import io.flutter.pub.PubRoot;
@@ -42,7 +43,7 @@ public void actionPerformed(@NotNull AnActionEvent event) {
       if (workspace != null) {
         FileDocumentManager.getInstance().saveAllDocuments();
         startCommandInBazelContext(project, workspace, event);
-        analyticsData.add("inBazelContext", true);
+        analyticsData.add(AnalyticsConstants.IN_BAZEL_CONTEXT, true);
         Analytics.report(analyticsData);
         return;
       }
@@ -51,7 +52,7 @@ public void actionPerformed(@NotNull AnActionEvent event) {
     final FlutterSdk sdk = project != null ? FlutterSdk.getFlutterSdk(project) : null;
     if (sdk == null) {
       showMissingSdkDialog(project);
-      analyticsData.add("missingSdk", true);
+      analyticsData.add(AnalyticsConstants.MISSING_SDK, true);
       Analytics.report(analyticsData);
       return;
     }

src/io/flutter/actions/ReloadFlutterApp.java

@@ -13,6 +13,7 @@
 import io.flutter.FlutterBundle;
 import io.flutter.FlutterConstants;
 import io.flutter.analytics.Analytics;
+import io.flutter.analytics.AnalyticsConstants;
 import io.flutter.analytics.AnalyticsData;
 import io.flutter.run.FlutterReloadManager;
 import io.flutter.run.daemon.FlutterApp;
@@ -49,7 +50,7 @@ public void actionPerformed(@NotNull AnActionEvent e) {
     // If the shift key is held down, perform a restart. We check to see if we're being invoked from the
     // 'GoToAction' dialog. If so, the modifiers are for the command that opened the go-to action dialog.
     final boolean shouldRestart = (e.getModifiers() & InputEvent.SHIFT_MASK) != 0 && !"GoToAction".equals(e.getPlace());
-    analyticsData.add("requiresRestart", shouldRestart);
+    analyticsData.add(AnalyticsConstants.REQUIRES_RESTART, shouldRestart);
 
     var reloadManager = FlutterReloadManager.getInstance(project);
     if (reloadManager == null) return;
@@ -61,7 +62,7 @@ public void actionPerformed(@NotNull AnActionEvent e) {
       // Else perform a hot reload.
       reloadManager.saveAllAndReload(getApp(), FlutterConstants.RELOAD_REASON_MANUAL);
     }
-    
+
     Analytics.report(analyticsData);
   }
 

src/io/flutter/actions/RestartFlutterApp.java

@@ -17,6 +17,7 @@
 import io.flutter.FlutterConstants;
 import io.flutter.FlutterMessages;
 import io.flutter.analytics.Analytics;
+import io.flutter.analytics.AnalyticsConstants;
 import io.flutter.analytics.AnalyticsData;
 import io.flutter.bazel.WorkspaceCache;
 import io.flutter.run.FlutterReloadManager;
@@ -65,7 +66,7 @@ public void actionPerformed(@NotNull AnActionEvent e) {
         NotificationType.INFORMATION);
       Notifications.Bus.notify(notification, project);
 
-      analyticsData.add("google3", true);
+      analyticsData.add(AnalyticsConstants.GOOGLE3, true);
 
       // We only want to show this notification once.
       FlutterSettings.getInstance().setShowBazelHotRestartWarning(false);

src/io/flutter/analytics/Analytics.kt

@@ -14,19 +14,15 @@ object Analytics {
   private val reporter = NoOpReporter
 
   @JvmStatic
-  fun report(data: AnalyticsData) = reporter.report(data)
+  fun report(data: AnalyticsData) = data.reportTo(reporter)
 }
 
 abstract class AnalyticsReporter {
-
-  fun report(data: AnalyticsData) = data.reportTo(this)
-
   internal abstract fun process(data: AnalyticsData)
 }
 
 internal object PrintingReporter : AnalyticsReporter() {
   override fun process(data: AnalyticsData) = println(data.data)
-
 }
 
 internal object NoOpReporter : AnalyticsReporter() {
@@ -37,7 +33,7 @@ abstract class AnalyticsData(type: String) {
   val data = mutableMapOf<String, Any>()
 
   init {
-    add("type", type)
+    add(AnalyticsConstants.TYPE, type)
   }
 
   companion object {
@@ -50,15 +46,17 @@ abstract class AnalyticsData(type: String) {
     )
   }
 
-  fun add(key: String, value: Boolean) {
+  fun <T> add(key: DataValue<T>, value: T) = key.addTo(this, value)
+
+  internal operator fun set(key: String, value: Boolean) {
     data[key] = value
   }
 
-  fun add(key: String, value: Int) {
+  internal operator fun set(key: String, value: Int) {
     data[key] = value
   }
 
-  fun add(key: String, value: String) {
+  internal operator fun set(key: String, value: String) {
     data[key] = value
   }
 
@@ -75,8 +73,8 @@ abstract class AnalyticsData(type: String) {
 class ActionData(private val id: String?, private val place: String) : AnalyticsData("action") {
 
   init {
-    id?.let { add("id", it) }
-    add("place", place)
+    id?.let { add(AnalyticsConstants.ID, it) }
+    add(AnalyticsConstants.PLACE, place)
   }
 
   override fun reportTo(reporter: AnalyticsReporter) {
@@ -85,3 +83,78 @@ class ActionData(private val id: String?, private val place: String) : Analytics
     super.reportTo(reporter)
   }
 }
+
+/**
+ * Defines standard keys for analytics data properties.
+ *
+ * The properties are exposed as `@JvmField`s to be easily accessible as static
+ * fields from Java.
+ */
+object AnalyticsConstants {
+  /**
+   * Indicates if the project is a Google3 project.
+   */
+  @JvmField
+  val GOOGLE3 = BooleanValue("google3")
+
+  /**
+   * The unique identifier for an action or event.
+   */
+  @JvmField
+  val ID = StringValue("id")
+
+  /**
+   * Indicates if the project is in a Bazel context.
+   */
+  @JvmField
+  val IN_BAZEL_CONTEXT = BooleanValue("inBazelContext")
+
+  /**
+   * Indicates if the Flutter SDK is missing.
+   */
+  @JvmField
+  val MISSING_SDK = BooleanValue("missingSdk")
+
+  /**
+   * The UI location where an action was invoked, as provided by
+   * [com.intellij.openapi.actionSystem.PlaceProvider.getPlace] (for example, "MainMenu",
+   * "MainToolbar", "EditorPopup", "GoToAction", etc).
+   */
+  @JvmField
+  val PLACE = StringValue("place")
+
+  /**
+   * Indicates if a restart is required for a hot reload request.
+   */
+  @JvmField
+  val REQUIRES_RESTART = BooleanValue("requiresRestart")
+
+  /**
+   * The type of the analytics event (e.g., "action", ...).
+   */
+  @JvmField
+  val TYPE = StringValue("type")
+}
+
+
+sealed class DataValue<T>(val name: String) {
+  abstract fun addTo(data: AnalyticsData, value: T);
+}
+
+class StringValue(name: String) : DataValue<String>(name) {
+  override fun addTo(data: AnalyticsData, value: String) {
+    data[name] = value
+  }
+}
+
+class IntValue(name: String) : DataValue<Int>(name) {
+  override fun addTo(data: AnalyticsData, value: Int) {
+    data[name] = value
+  }
+}
+
+class BooleanValue(name: String) : DataValue<Boolean>(name) {
+  override fun addTo(data: AnalyticsData, value: Boolean) {
+    data[name] = value
+  }
+}