feat: Add app vs default dev-bundle statistics (#16103) (#16121)

* feat: Add app vs default dev-bundle statistics

* add statistics about re-bundling reason

* Better names

---------

Co-authored-by: Mikhail Shabarov <61410877+mshabarov@users.noreply.github.com>
Co-authored-by: Teppo Kurki <teppo.kurki@vaadin.com>
Co-authored-by: Manuel Carrasco Moñino <manolo@vaadin.com>

Author: 4 people

flow-server/src/main/java/com/vaadin/flow/server/frontend/NodeTasks.java

@@ -95,6 +95,10 @@ public NodeTasks(Options options) {
 
         final FeatureFlags featureFlags = options.getFeatureFlags();
 
+        if (options.isFrontendHotdeploy()) {
+            UsageStatistics.markAsUsed("flow/hotdeploy", null);
+        }
+
         if (options.isEnablePackagesUpdate() || options.isEnableImportsUpdate()
                 || options.isEnableWebpackConfigUpdate()) {
             frontendDependencies = new FrontendDependenciesScanner.FrontendDependenciesScannerFactory()
@@ -106,14 +110,21 @@ public NodeTasks(Options options) {
             // determine if we need a rebuild as the check happens immediately
             // and no update tasks are executed before it.
             if (!options.isProductionMode() && options.isDevBundleBuild()) {
-                UsageStatistics.markAsUsed("flow/expressBuild", null);
                 if (TaskRunDevBundleBuild.needsBuild(options,
                         frontendDependencies, classFinder)) {
                     options.withRunNpmInstall(true);
                     options.withCopyTemplates(true);
+                    UsageStatistics.markAsUsed("flow/app-dev-bundle", null);
                 } else {
                     // A dev bundle build is not needed after all, skip it
                     options.withDevBundleBuild(false);
+                    File devBundleFolder = FrontendUtils
+                            .getDevBundleFolder(options.getNpmFolder());
+                    if (devBundleFolder.exists()) {
+                        UsageStatistics.markAsUsed("flow/app-dev-bundle", null);
+                    } else {
+                        UsageStatistics.markAsUsed("flow/dev-bundle", null);
+                    }
                 }
             }
 

flow-server/src/main/java/com/vaadin/flow/server/frontend/TaskRunDevBundleBuild.java

@@ -45,6 +45,7 @@
 import com.vaadin.flow.component.WebComponentExporterFactory;
 import com.vaadin.flow.internal.JsonUtils;
 import com.vaadin.flow.internal.StringUtil;
+import com.vaadin.flow.internal.UsageStatistics;
 import com.vaadin.flow.server.Constants;
 import com.vaadin.flow.server.ExecutionFailedException;
 import com.vaadin.flow.server.frontend.scanner.ClassFinder;
@@ -182,21 +183,29 @@ protected static boolean needsBuildInternal(Options options,
                 .getPackages();
 
         if (!hashAndBundleModulesEqual(statsJson, packageJson, npmPackages)) {
+            UsageStatistics.markAsUsed("flow/rebundle-reason-missing-package",
+                    null);
             // Hash in the project doesn't match the bundle hash or NpmPackages
             // are found missing in bundle.
             return true;
         }
         if (!frontendImportsFound(statsJson, options, finder,
                 frontendDependencies)) {
+            UsageStatistics.markAsUsed(
+                    "flow/rebundle-reason-missing-frontend-import", null);
             return true;
         }
 
         if (themeConfigurationChanged(options, statsJson,
                 frontendDependencies)) {
+            UsageStatistics.markAsUsed(
+                    "flow/rebundle-reason-changed-theme-config", null);
             return true;
         }
 
         if (exportedWebComponents(statsJson, finder)) {
+            UsageStatistics.markAsUsed(
+                    "flow/rebundle-reason-added-exported-component", null);
             return true;
         }