Fix: Avoid analyzing /favicon.ico multiple times

Fix #427
webhintio · Aug 17, 2017 · 41df7f0 · 41df7f0
1 parent 941d439
commit 41df7f0
Showing 1 changed file with 20 additions and 4 deletions.
diff --git a/src/lib/connectors/shared/remote-debugging-connector.ts b/src/lib/connectors/shared/remote-debugging-connector.ts
@@ -326,7 +326,12 @@ export class Connector implements IConnector {
             };
         }
 
-        if (hasAttributeWithValue(data.element, 'link', 'rel', 'icon')) {
+        const hasFaviconLinkTag = hasAttributeWithValue(data.element, 'link', 'rel', 'icon');
+        // If favicon is not present in the html, CDP will send a request to get favicon from the root directory.
+        // We should set the tag to true in this case to avoid fetching favicon twice.
+        const hasFaviconInRootDir = data.request.url.endsWith('/favicon.ico');
+
+        if (hasFaviconLinkTag || hasFaviconInRootDir) {
             this._faviconLoaded = true;
         }
 
@@ -487,8 +492,12 @@ export class Connector implements IConnector {
      * * uses the `src` attribute of `<link rel="icon">` if present.
      * * uses `favicon.ico` and the final url after redirects.
      */
-    private async getFavicon(element?: AsyncHTMLElement) {
-        const href = element ? element.getAttribute('href') : '/favicon.ico';
+    private async getFavicon(element: AsyncHTMLElement) {
+        const href = element.getAttribute('href');
+
+        if (!href) { // `href` is empty.
+            return;
+        }
 
         try {
             debug(`resource ${href} to be fetched`);
@@ -545,7 +554,14 @@ export class Connector implements IConnector {
                     }
 
                     if (!this._faviconLoaded) {
-                        await this.getFavicon((await this._dom.querySelectorAll('link[rel~="icon"]'))[0]);
+                        // We don't need to consider fetching favicon from the root here.
+                        // It should never get to this point if favicon is in the root directory.
+                        const faviconElement = (await this._dom.querySelectorAll('link[rel~="icon"]'))[0];
+
+                        if (faviconElement) {
+                            await this.getFavicon(faviconElement);
+                        }
+
                     }
 
                     await this._server.emitAsync('scan::end', event);