Merge pull request #19174 from brave/cosmetic-filtering-debug-logging

Add `#brave-adblock-scriptlet-debug-logs` flag for filter authors
brave · Jul 8, 2023 · e29428b · e29428b
2 parents 1e9250d + 7995de2
commit e29428b
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Showing 5 changed files with 65 additions and 4 deletions.
diff --git a/browser/about_flags.cc b/browser/about_flags.cc
@@ -522,6 +522,16 @@
           FEATURE_VALUE_TYPE(brave_shields::features::                         \
                                  kBraveAdblockMobileNotificationsListDefault), \
       },                                                                       \
+      {                                                                        \
+          "brave-adblock-scriptlet-debug-logs",                                \
+          "Enable debug logging for scriptlet injections",                     \
+          "Enable console debugging for scriptlets injected by cosmetic "      \
+          "filtering, exposing additional information that can be useful for " \
+          "filter authors.",                                                   \
+          kOsDesktop,                                                          \
+          FEATURE_VALUE_TYPE(                                                  \
+              brave_shields::features::kBraveAdblockScriptletDebugLogs),       \
+      },                                                                       \
       {                                                                        \
           "brave-dark-mode-block",                                             \
           "Enable dark mode blocking fingerprinting protection",               \

diff --git a/browser/brave_shields/ad_block_service_browsertest.cc b/browser/brave_shields/ad_block_service_browsertest.cc
@@ -87,6 +87,7 @@ using brave_shields::features::kBraveAdblockCollapseBlockedElements;
 using brave_shields::features::kBraveAdblockCookieListDefault;
 using brave_shields::features::kBraveAdblockCosmeticFiltering;
 using brave_shields::features::kBraveAdblockDefault1pBlocking;
+using brave_shields::features::kBraveAdblockScriptletDebugLogs;
 using brave_shields::features::kCosmeticFilteringJsPerformance;
 
 AdBlockServiceTest::AdBlockServiceTest()
@@ -2255,6 +2256,47 @@ IN_PROC_BROWSER_TEST_F(AdBlockServiceTest, CosmeticFilteringWindowScriptlet) {
   EXPECT_EQ(base::Value(true), result.value);
 }
 
+class ScriptletDebugLogsFlagEnabledTest : public AdBlockServiceTest {
+ public:
+  ScriptletDebugLogsFlagEnabledTest() {
+    feature_list_.InitAndEnableFeature(kBraveAdblockScriptletDebugLogs);
+  }
+
+ private:
+  base::test::ScopedFeatureList feature_list_;
+};
+
+// Test that scriptlet injection has access to `canDebug` inside of
+// `scriptletGlobals`, and that it is set to `true`.
+IN_PROC_BROWSER_TEST_F(ScriptletDebugLogsFlagEnabledTest, CanDebugSetToTrue) {
+  ASSERT_TRUE(InstallDefaultAdBlockExtension());
+  std::string scriptlet =
+      "(function() {"
+      "  if (scriptletGlobals.get('canDebug')) {"
+      "    window.success = true;"
+      "  }"
+      "})();";
+  std::string scriptlet_base64;
+  base::Base64Encode(scriptlet, &scriptlet_base64);
+  UpdateAdBlockInstanceWithRules(
+      "b.com##+js(debuggable)",
+      "[{"
+      "\"name\": \"debuggable\","
+      "\"aliases\": [],"
+      "\"kind\": {\"mime\": \"application/javascript\"},"
+      "\"content\": \"" +
+          scriptlet_base64 + "\"}]");
+
+  GURL tab_url =
+      embedded_test_server()->GetURL("b.com", "/cosmetic_filtering.html");
+  ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), tab_url));
+
+  content::WebContents* contents =
+      browser()->tab_strip_model()->GetActiveWebContents();
+
+  EXPECT_EQ(true, EvalJs(contents, R"(window.success)"));
+}
+
 // Test scriptlet injection with DeAMP enabled
 IN_PROC_BROWSER_TEST_F(AdBlockServiceTest, CheckForDeAmpPref) {
   std::string scriptlet =

diff --git a/components/brave_shields/common/features.cc b/components/brave_shields/common/features.cc
@@ -41,6 +41,9 @@ BASE_FEATURE(kBraveAdblockCookieListOptIn,
 BASE_FEATURE(kBraveAdblockCosmeticFiltering,
              "BraveAdblockCosmeticFiltering",
              base::FEATURE_ENABLED_BY_DEFAULT);
+BASE_FEATURE(kBraveAdblockScriptletDebugLogs,
+             "BraveAdblockScriptletDebugLogs",
+             base::FEATURE_DISABLED_BY_DEFAULT);
 BASE_FEATURE(kBraveAdblockCspRules,
              "BraveAdblockCspRules",
              base::FEATURE_ENABLED_BY_DEFAULT);

diff --git a/components/brave_shields/common/features.h b/components/brave_shields/common/features.h
@@ -21,6 +21,7 @@ BASE_DECLARE_FEATURE(kBraveAdblockCookieListOptIn);
 BASE_DECLARE_FEATURE(kBraveAdblockCosmeticFiltering);
 BASE_DECLARE_FEATURE(kBraveAdblockCspRules);
 BASE_DECLARE_FEATURE(kBraveAdblockMobileNotificationsListDefault);
+BASE_DECLARE_FEATURE(kBraveAdblockScriptletDebugLogs);
 BASE_DECLARE_FEATURE(kBraveDomainBlock);
 BASE_DECLARE_FEATURE(kBraveDomainBlock1PES);
 BASE_DECLARE_FEATURE(kBraveExtensionNetworkBlocking);

diff --git a/components/cosmetic_filters/renderer/cosmetic_filters_js_handler.cc b/components/cosmetic_filters/renderer/cosmetic_filters_js_handler.cc
@@ -45,7 +45,7 @@ const char kObservingScriptletEntryPoint[] =
 
 const char kScriptletInitScript[] =
     R"((function() {
-          let text = '(function() {\nconst scriptletGlobals = new Map();\nlet deAmpEnabled = %s;\n' + %s + '})()';
+          let text = '(function() {\nconst scriptletGlobals = new Map(%s);\nlet deAmpEnabled = %s;\n' + %s + '})()';
           let script;
           try {
             script = document.createElement('script');
@@ -411,11 +411,16 @@ void CosmeticFiltersJSHandler::ApplyRules(bool de_amp_enabled) {
 
   std::string scriptlet_script;
   base::Value* injected_script = resources_dict_->Find("injected_script");
+
   if (injected_script &&
       base::JSONWriter::Write(*injected_script, &scriptlet_script)) {
-    scriptlet_script = base::StringPrintf(kScriptletInitScript,
-                                          de_amp_enabled ? "true" : "false",
-                                          scriptlet_script.c_str());
+    const bool scriptlet_debug_enabled = base::FeatureList::IsEnabled(
+        brave_shields::features::kBraveAdblockScriptletDebugLogs);
+
+    scriptlet_script = base::StringPrintf(
+        kScriptletInitScript,
+        scriptlet_debug_enabled ? "[[\"canDebug\", true]]" : "",
+        de_amp_enabled ? "true" : "false", scriptlet_script.c_str());
   }
   if (!scriptlet_script.empty()) {
     web_frame->ExecuteScriptInIsolatedWorld(