Add jsProfilingEnabled option for WebView responses

android/capacitor/src/main/java/com/getcapacitor/Bridge.java

@@ -272,7 +272,8 @@ private void loadWebView() {
                 Logger.warn("Invalid url, using fallback");
             }
         }
-        localServer = new WebViewLocalServer(context, this, injector, authorities, html5mode);
+        boolean jsProfilingEnabled = config.isJsProfilingEnabled();
+        localServer = new WebViewLocalServer(context, this, injector, authorities, html5mode, jsProfilingEnabled);
         localServer.hostAssets(DEFAULT_WEB_ASSET_DIR);
 
         Logger.debug("Loading app at " + appUrl);

android/capacitor/src/main/java/com/getcapacitor/CapConfig.java

@@ -54,6 +54,7 @@ public class CapConfig {
     private String errorPath;
     private boolean zoomableWebView = false;
     private boolean resolveServiceWorkerRequests = true;
+    private boolean jsProfilingEnabled = false;
 
     // Embedded
     private String startPath;
@@ -181,6 +182,7 @@ private CapConfig(Builder builder) {
         this.errorPath = builder.errorPath;
         this.zoomableWebView = builder.zoomableWebView;
         this.resolveServiceWorkerRequests = builder.resolveServiceWorkerRequests;
+        this.jsProfilingEnabled = builder.jsProfilingEnabled;
 
         // Embedded
         this.startPath = builder.startPath;
@@ -286,6 +288,7 @@ private void deserializeConfig(@Nullable Context context) {
         webContentsDebuggingEnabled = JSONUtils.getBoolean(configJSON, "android.webContentsDebuggingEnabled", isDebug);
         zoomableWebView = JSONUtils.getBoolean(configJSON, "android.zoomEnabled", JSONUtils.getBoolean(configJSON, "zoomEnabled", false));
         resolveServiceWorkerRequests = JSONUtils.getBoolean(configJSON, "android.resolveServiceWorkerRequests", true);
+        jsProfilingEnabled = JSONUtils.getBoolean(configJSON, "android.jsProfilingEnabled", false);
 
         String logBehavior = JSONUtils.getString(
             configJSON,
@@ -382,6 +385,10 @@ public boolean isResolveServiceWorkerRequests() {
         return resolveServiceWorkerRequests;
     }
 
+    public boolean isJsProfilingEnabled() {
+        return jsProfilingEnabled;
+    }
+
     public boolean isWebContentsDebuggingEnabled() {
         return webContentsDebuggingEnabled;
     }
@@ -582,6 +589,7 @@ public static class Builder {
         private int minHuaweiWebViewVersion = DEFAULT_HUAWEI_WEBVIEW_VERSION;
         private boolean zoomableWebView = false;
         private boolean resolveServiceWorkerRequests = true;
+        private boolean jsProfilingEnabled = false;
 
         // Embedded
         private String startPath = null;
@@ -686,6 +694,11 @@ public Builder setResolveServiceWorkerRequests(boolean resolveServiceWorkerReque
             return this;
         }
 
+        public Builder setJsProfilingEnabled(boolean jsProfilingEnabled) {
+            this.jsProfilingEnabled = jsProfilingEnabled;
+            return this;
+        }
+
         public Builder setWebContentsDebuggingEnabled(boolean webContentsDebuggingEnabled) {
             this.webContentsDebuggingEnabled = webContentsDebuggingEnabled;
             return this;

android/capacitor/src/main/java/com/getcapacitor/WebViewLocalServer.java

@@ -63,6 +63,7 @@ public class WebViewLocalServer {
     private final boolean html5mode;
     private final JSInjector jsInjector;
     private final Bridge bridge;
+    private final boolean jsProfilingEnabled;
 
     /**
      * A handler that produces responses for paths on the virtual asset server.
@@ -133,13 +134,14 @@ public Map<String, String> getResponseHeaders() {
         }
     }
 
-    WebViewLocalServer(Context context, Bridge bridge, JSInjector jsInjector, ArrayList<String> authorities, boolean html5mode) {
+    WebViewLocalServer(Context context, Bridge bridge, JSInjector jsInjector, ArrayList<String> authorities, boolean html5mode, boolean jsProfilingEnabled) {
         uriMatcher = new UriMatcher(null);
         this.html5mode = html5mode;
         this.protocolHandler = new AndroidProtocolHandler(context.getApplicationContext());
         this.authorities = authorities;
         this.bridge = bridge;
         this.jsInjector = jsInjector;
+        this.jsProfilingEnabled = jsProfilingEnabled;
     }
 
     private static Uri parseAndVerifyUrl(String url) {
@@ -619,7 +621,13 @@ private void createHostingDetails() {
             throw new IllegalArgumentException("assetPath cannot contain the '*' character.");
         }
 
-        PathHandler handler = new PathHandler() {
+        Map<String, String> customHeaders = null;
+        if (jsProfilingEnabled) {
+            customHeaders = new HashMap<>();
+            customHeaders.put("Document-Policy", "js-profiling");
+        }
+
+        PathHandler handler = new PathHandler(null, null, 200, "OK", customHeaders) {
             @Override
             public InputStream handle(Uri url) {
                 InputStream stream = null;

cli/src/declarations.ts

@@ -297,6 +297,17 @@ export interface CapacitorConfig {
      * @default true
      */
     resolveServiceWorkerRequests?: boolean;
+
+    /**
+     * Enable JavaScript profiling by adding the `Document-Policy: js-profiling`
+     * HTTP response header to WebView responses.
+     *
+     * This header is required for the JS Self-Profiling API to work in the WebView.
+     *
+     * @since 8.0.0
+     * @default false
+     */
+    jsProfilingEnabled?: boolean;
   };
 
   ios?: {