Implement logic in help app delegate to use the Local Search Service.

- Added |IsLSSEnabled| to help_app_ui.mojom.
- LSS methods in receiver forward requests via message pipe.
- Implement message handlers in browser_proxy.
- Added browsertest to ensure LSS methods used by delegate.

Bug: b/166047521
Change-Id: Iadc5fba94e79631d7b293be0e5b917f72bdc8fc8
Cq-Include-Trybots: chrome/try:linux-chromeos-chrome
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2437560Reviewed-by: Trent Apted <tapted@chromium.org>
Reviewed-by: dstockwell <dstockwell@google.com>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Commit-Queue: Callistus Tan <callistus@google.com>
Cr-Commit-Position: refs/heads/master@{#813011}

chrome/browser/chromeos/web_applications/help_app_integration_browsertest.cc

@@ -47,6 +47,7 @@ class HelpAppIntegrationTest : public SystemWebAppIntegrationTest {
   HelpAppIntegrationTest() {
     scoped_feature_list_.InitWithFeatures(
         {chromeos::features::kHelpAppReleaseNotes,
+         chromeos::features::kHelpAppSearchServiceIntegration,
          chromeos::features::kReleaseNotesNotificationAllChannels},
         {});
   }
@@ -354,6 +355,45 @@ IN_PROC_BROWSER_TEST_P(HelpAppIntegrationTest, HelpAppV2ShowParentalControls) {
   EXPECT_EQ(expected_url, GetActiveWebContents()->GetVisibleURL());
 }
 
+// Test that the Help App delegate uses the local search service methods.
+IN_PROC_BROWSER_TEST_P(HelpAppIntegrationTest,
+                       HelpAppV2UsesLocalSearchServiceMethods) {
+  WaitForTestSystemAppInstall();
+  content::WebContents* web_contents = LaunchApp(web_app::SystemAppType::HELP);
+
+  // Script that adds a data item to the search index, then tries to find that
+  // data item.
+  constexpr char kScript[] = R"(
+    (async () => {
+      const delegate = document.querySelector('showoff-app').getDelegate();
+
+      await delegate.addOrUpdateSearchIndex([{
+        id: 'test-id',
+        title: 'foobar',
+        body: 'foo bar baz',
+        mainCategoryName: 'Help',
+        locale: 'en-US',
+      }]);
+
+      // Polling is required as addOrUpdateSearchIndex resolves before the
+      // search index is actually updated.
+      setInterval(async () => {
+        // Note that the LSS will fuzzy match into foobar.
+        const {results} = await delegate.findInSearchIndex('foober');
+        if (results && results.length === 1) {
+          window.domAutomationController.send(results[0].id);
+        }
+      }, 10);
+    })();
+  )";
+  std::string result;
+  // Use ExecuteScript instead of EvalJsInAppFrame because the script needs to
+  // run in the same world as the page's code.
+  EXPECT_TRUE(content::ExecuteScriptAndExtractString(
+      SandboxedWebUiAppTestBase::GetAppFrame(web_contents), kScript, &result));
+  EXPECT_EQ(result, "test-id");
+}
+
 // Test that the Help App opens when Gesture help requested.
 IN_PROC_BROWSER_TEST_P(HelpAppAllProfilesIntegrationTest, HelpAppOpenGestures) {
   WaitForTestSystemAppInstall();

chromeos/components/help_app_ui/help_app_page_handler.cc

@@ -6,13 +6,18 @@
 
 #include <utility>
 
+#include "base/feature_list.h"
 #include "chromeos/components/help_app_ui/help_app_ui.h"
 #include "chromeos/components/help_app_ui/help_app_ui_delegate.h"
+#include "chromeos/constants/chromeos_features.h"
 
 HelpAppPageHandler::HelpAppPageHandler(
     chromeos::HelpAppUI* help_app_ui,
     mojo::PendingReceiver<help_app_ui::mojom::PageHandler> receiver)
-    : receiver_(this, std::move(receiver)), help_app_ui_(help_app_ui) {}
+    : receiver_(this, std::move(receiver)),
+      help_app_ui_(help_app_ui),
+      is_lss_enabled_(base::FeatureList::IsEnabled(
+          chromeos::features::kHelpAppSearchServiceIntegration)) {}
 
 HelpAppPageHandler::~HelpAppPageHandler() = default;
 
@@ -25,3 +30,7 @@ void HelpAppPageHandler::OpenFeedbackDialog(
 void HelpAppPageHandler::ShowParentalControls() {
   help_app_ui_->delegate()->ShowParentalControls();
 }
+
+void HelpAppPageHandler::IsLssEnabled(IsLssEnabledCallback callback) {
+  std::move(callback).Run(is_lss_enabled_);
+}

chromeos/components/help_app_ui/help_app_page_handler.h

@@ -28,10 +28,12 @@ class HelpAppPageHandler : public help_app_ui::mojom::PageHandler {
   // help_app_ui::mojom::PageHandler:
   void OpenFeedbackDialog(OpenFeedbackDialogCallback callback) override;
   void ShowParentalControls() override;
+  void IsLssEnabled(IsLssEnabledCallback callback) override;
 
  private:
   mojo::Receiver<help_app_ui::mojom::PageHandler> receiver_;
   chromeos::HelpAppUI* help_app_ui_;  // Owns |this|.
+  bool is_lss_enabled_;
 };
 
 #endif  // CHROMEOS_COMPONENTS_HELP_APP_UI_HELP_APP_PAGE_HANDLER_H_

chromeos/components/help_app_ui/help_app_ui.mojom

@@ -19,4 +19,7 @@ interface PageHandler {
 
   // Opens the parental controls part of OS settings.
   ShowParentalControls();
+
+  // Returns true if Local Search Service integration is enabled.
+  IsLssEnabled() => (bool enabled);
 };

chromeos/components/help_app_ui/resources/browser_proxy.js

@@ -11,16 +11,32 @@ helpAppUi.mojom.PageHandlerFactory.getRemote().createPageHandler(
     help_app.handler.$.bindNewPipeAndPassReceiver());
 
 // Set up an index remote to talk to Local Search Service.
-// TODO(b/166047521): Define and use API to make calls to this from untrusted
-// context.
+/** @type {!chromeos.localSearchService.mojom.IndexProxyRemote} */
 const indexRemote = chromeos.localSearchService.mojom.IndexProxy.getRemote();
 
 const GUEST_ORIGIN = 'chrome-untrusted://help-app';
-const guestFrame = /** @type {!HTMLIFrameElement} */ (
-    document.createElement('iframe'));
+const guestFrame =
+    /** @type {!HTMLIFrameElement} */ (document.createElement('iframe'));
 guestFrame.src = `${GUEST_ORIGIN}${location.pathname}`;
 document.body.appendChild(guestFrame);
 
+// Cached result whether Local Search Service is enabled.
+/** @type {Promise<boolean>} */
+const isLssEnabled =
+    help_app.handler.isLssEnabled().then(result => result.enabled);
+
+/**
+ * @param {string} s
+ * @return {!mojoBase.mojom.String16Spec}
+ */
+function toString16(s) {
+  return /** @type {!mojoBase.mojom.String16Spec} */ (
+      {data: Array.from(s, (/** @type {string} */ c) => c.charCodeAt())});
+}
+const TITLE_ID = 'title';
+const BODY_ID = 'body';
+const CATEGORY_ID = 'main-category';
+
 /**
  * A pipe through which we can send messages to the guest frame.
  * Use an undefined `target` to find the <iframe> automatically.
@@ -28,9 +44,9 @@ document.body.appendChild(guestFrame);
  * throw exceptions that are handled on the other side of the pipe (in the guest
  * frame), not on this side.
  */
-const guestMessagePipe =
-    new MessagePipe('chrome-untrusted://help-app', /*target=*/ undefined,
-        /*rethrowErrors=*/ false);
+const guestMessagePipe = new MessagePipe(
+    'chrome-untrusted://help-app', /*target=*/ undefined,
+    /*rethrowErrors=*/ false);
 
 guestMessagePipe.registerHandler(Message.OPEN_FEEDBACK_DIALOG, () => {
   return help_app.handler.openFeedbackDialog();
@@ -39,3 +55,89 @@ guestMessagePipe.registerHandler(Message.OPEN_FEEDBACK_DIALOG, () => {
 guestMessagePipe.registerHandler(Message.SHOW_PARENTAL_CONTROLS, () => {
   help_app.handler.showParentalControls();
 });
+
+guestMessagePipe.registerHandler(
+    Message.ADD_OR_UPDATE_SEARCH_INDEX, async (message) => {
+      if (!(await isLssEnabled)) {
+        return;
+      }
+      const data_from_app =
+          /** @type {!Array<!helpApp.SearchableItem>} */ (message);
+      const data_to_send = data_from_app.map(searchable_item => {
+        const contents = [
+          {
+            id: TITLE_ID,
+            content: toString16(searchable_item.title),
+            weight: 1.0,
+          },
+          {
+            id: BODY_ID,
+            content: toString16(searchable_item.body),
+            weight: 0.2,
+          },
+          {
+            id: CATEGORY_ID,
+            content: toString16(searchable_item.mainCategoryName),
+            weight: 0.1,
+          },
+        ];
+        return {
+          id: searchable_item.id,
+          contents,
+          locale: searchable_item.locale,
+        };
+      });
+      indexRemote.addOrUpdate(data_to_send);
+    });
+
+guestMessagePipe.registerHandler(Message.CLEAR_SEARCH_INDEX, async () => {
+  if (!(await isLssEnabled)) {
+    return;
+  }
+  // TODO(b/166047521): Clear the index when that method is available.
+});
+
+guestMessagePipe.registerHandler(
+    Message.FIND_IN_SEARCH_INDEX, async (message) => {
+      if (!(await isLssEnabled)) {
+        return {results: null};
+      }
+      const response = await indexRemote.find(
+          toString16((/** @type {{query: string}} */ (message)).query),
+          /*max_results=*/ 100);
+      if (response.status !==
+              chromeos.localSearchService.mojom.ResponseStatus.kSuccess ||
+          !response.results) {
+        return {results: null};
+      }
+      const search_results =
+          /** @type {!Array<!chromeos.localSearchService.mojom.Result>} */ (
+              response.results);
+      // Sort results by decreasing score.
+      search_results.sort((a, b) => b.score - a.score);
+      /** @type {!Array<!helpApp.SearchResult>} */
+      const results = search_results.map(result => {
+        /** @type {!Array<!helpApp.Position>} */
+        const titlePositions = [];
+        /** @type {!Array<!helpApp.Position>} */
+        const bodyPositions = [];
+        for (const position of result.positions) {
+          if (position.contentId === TITLE_ID) {
+            titlePositions.push(
+                {length: position.length, start: position.start});
+          } else if (position.contentId === BODY_ID) {
+            bodyPositions.push(
+                {length: position.length, start: position.start});
+          }
+        }
+        // Sort positions by start index.
+        titlePositions.sort((a, b) => a.start - b.start);
+        bodyPositions.sort((a, b) => a.start - b.start);
+        return {
+          id: result.id,
+          titlePositions,
+          bodyPositions,
+        };
+      });
+      return {results};
+    });

chromeos/components/help_app_ui/resources/help_app.externs.js

@@ -77,12 +77,14 @@ helpApp.SearchResult = function() {};
 /** @type {string} */
 helpApp.SearchResult.prototype.id;
 /**
- * List of positions corresponding to the title. Used in snippet.
+ * List of positions corresponding to the title, sorted by start index. Used in
+ * snippet.
  * @type {?Array<!helpApp.Position>}
  */
 helpApp.SearchResult.prototype.titlePositions;
 /**
- * List of positions corresponding to the body. Used in snippet.
+ * List of positions corresponding to the body sorted by start index. Used in
+ * snippet.
  * @type {?Array<!helpApp.Position>}
  */
 helpApp.SearchResult.prototype.bodyPositions;

chromeos/components/help_app_ui/resources/message_types.js

@@ -13,5 +13,8 @@
  */
 const Message = {
   OPEN_FEEDBACK_DIALOG: 'open-feedback-dialog',
-  SHOW_PARENTAL_CONTROLS: 'show-parental-controls'
+  SHOW_PARENTAL_CONTROLS: 'show-parental-controls',
+  ADD_OR_UPDATE_SEARCH_INDEX: 'add-or-update-search-index',
+  CLEAR_SEARCH_INDEX: 'clear-search-index',
+  FIND_IN_SEARCH_INDEX: 'find-in-search-index'
 };

chromeos/components/help_app_ui/resources/receiver.js

@@ -24,15 +24,27 @@ const DELEGATE = {
   async showParentalControls() {
     await parentMessagePipe.sendMessage(Message.SHOW_PARENTAL_CONTROLS);
   },
-  // TODO(b/166047521): Complete the implementation of these.
-  async addOrUpdateSearchIndex() {
-    return;
+  /**
+   * @override
+   * @param {!Array<!helpApp.SearchableItem>} data
+   */
+  async addOrUpdateSearchIndex(data) {
+    await parentMessagePipe.sendMessage(
+        Message.ADD_OR_UPDATE_SEARCH_INDEX, data);
   },
   async clearSearchIndex() {
+    // TODO(b/166047521): Send the message when clear search index has been
+    // implemented. the index when that method is available.
     return;
   },
-  async findInSearchIndex() {
-    return {results: null};
+  /**
+   * @override
+   * @param {string} query
+   * @return {!Promise<!helpApp.FindResponse>}
+   */
+  findInSearchIndex(query) {
+    return /** @type {!Promise<!helpApp.FindResponse>} */ (
+        parentMessagePipe.sendMessage(Message.FIND_IN_SEARCH_INDEX, {query}));
   },
 };
 

chromeos/components/help_app_ui/test/help_app_ui_browsertest.js

@@ -44,8 +44,6 @@ var HelpAppUIBrowserTest = class extends testing.Test {
   }
 };
 
-const toString16 = s => ({data: Array.from(s, c => c.charCodeAt())});
-
 // Tests that chrome://help-app goes somewhere instead of 404ing or crashing.
 TEST_F('HelpAppUIBrowserTest', 'HasChromeSchemeURL', () => {
   const guest = document.querySelector('iframe');
@@ -64,6 +62,7 @@ TEST_F('HelpAppUIBrowserTest', 'HasTitleAndLang', () => {
 
 // Tests that we can make calls to the LSS to search.
 TEST_F('HelpAppUIBrowserTest', 'CanSearchViaLSSIndex', async () => {
+  const toString16 = s => ({data: Array.from(s, c => c.charCodeAt())});
   const result = await indexRemote.find(toString16('search string!'), 100);
 
   // Status 3 corresponds to kEmptyIndex.