Only allow same origin (domain + subdomains) for preload

GoogleChrome · May 4, 2018 · 3815f12 · 3815f12
1 parent f0558f7
commit 3815f12
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Showing 3 changed files with 77 additions and 7 deletions.
diff --git a/lighthouse-core/audits/uses-rel-preload.js b/lighthouse-core/audits/uses-rel-preload.js
@@ -5,6 +5,7 @@
  */
 'use strict';
 
+const URL = require('../lib/url-shim');
 const Audit = require('./audit');
 const UnusedBytes = require('./byte-efficiency/byte-efficiency-audit');
 const THRESHOLD_IN_MS = 100;
@@ -58,6 +59,20 @@ class UsesRelPreloadAudit extends Audit {
     return requests;
   }
 
+  /**
+   *
+   * @param {LH.WebInspector.NetworkRequest} request
+   * @param {LH.WebInspector.NetworkRequest} mainResource
+   * @return {boolean}
+   */
+  static shouldPreload(request, mainResource) {
+    if (request._isLinkPreload || request.protocol === 'data') {
+      return false;
+    }
+
+    return URL.rootDomainsMatch(request.url, mainResource.url);
+  }
+
   /**
    * Computes the estimated effect of preloading all the resources.
    * @param {Set<string>} urls The array of byte savings results per resource
@@ -117,6 +132,7 @@ class UsesRelPreloadAudit extends Audit {
       const originalNode = originalNodesByRecord.get(node.record);
       const timingAfter = simulationAfterChanges.nodeTimings.get(node);
       const timingBefore = simulationBeforeChanges.nodeTimings.get(originalNode);
+
       // @ts-ignore TODO(phulce): fix timing typedef
       const wastedMs = Math.round(timingBefore.endTime - timingAfter.endTime);
       if (wastedMs < THRESHOLD_IN_MS) continue;
@@ -163,8 +179,8 @@ class UsesRelPreloadAudit extends Audit {
     /** @type {Set<string>} */
     const urls = new Set();
     for (const networkRecord of criticalRequests) {
-      if (!networkRecord._isLinkPreload && networkRecord.protocol !== 'data') {
-        urls.add(networkRecord._url);
+      if (UsesRelPreloadAudit.shouldPreload(networkRecord, mainResource)) {
+        urls.add(networkRecord.url);
       }
     }
 

diff --git a/lighthouse-core/lib/url-shim.js b/lighthouse-core/lib/url-shim.js
@@ -87,6 +87,26 @@ class URLShim extends URL {
     }
   }
 
+  /**
+   * Check if rootDomains matches
+   *
+   * @param {string} urlA
+   * @param {string} urlB
+   */
+  static rootDomainsMatch(urlA, urlB) {
+    const urlAInfo = new URL(urlA);
+    const urlBInfo = new URL(urlB);
+
+    if (!urlAInfo.host || !urlBInfo.host) {
+      return false;
+    }
+
+    const urlARootDomain = urlAInfo.host.split('.').slice(-2).join('.');
+    const urlBRootDomain = urlBInfo.host.split('.').slice(-2).join('.');
+
+    return urlARootDomain === urlBRootDomain;
+  }
+
   /**
    * @param {string} url
    * @param {{numPathParts: number, preserveQuery: boolean, preserveHost: boolean}=} options

diff --git a/lighthouse-core/test/audits/uses-rel-preload-test.js b/lighthouse-core/test/audits/uses-rel-preload-test.js
@@ -53,10 +53,14 @@ describe('Performance: uses-rel-preload audit', () => {
     const mainDocumentNode = buildNode(2, 'http://www.example.com');
     const scriptNode = buildNode(3, 'http://www.example.com/script.js');
     const scriptAddedNode = buildNode(4, 'http://www.example.com/script-added.js');
+    const scriptSubNode = buildNode(5, 'http://sub.example.com/script-sub.js');
+    const scriptOtherNode = buildNode(6, 'http://otherdomain.com/script-other.js');
 
     mainDocumentNode.addDependency(rootNode);
     scriptNode.addDependency(mainDocumentNode);
     scriptAddedNode.addDependency(scriptNode);
+    scriptSubNode.addDependency(scriptNode);
+    scriptOtherNode.addDependency(scriptNode);
 
     mockGraph = rootNode;
     mockSimulator = {
@@ -68,19 +72,31 @@ describe('Performance: uses-rel-preload audit', () => {
         const mainDocumentNodeLocal = nodesByUrl.get(mainDocumentNode.record.url);
         const scriptNodeLocal = nodesByUrl.get(scriptNode.record.url);
         const scriptAddedNodeLocal = nodesByUrl.get(scriptAddedNode.record.url);
+        const scriptSubNodeLocal = nodesByUrl.get(scriptSubNode.record.url);
+        const scriptOtherNodeLocal = nodesByUrl.get(scriptOtherNode.record.url);
 
         const nodeTimings = new Map([
           [rootNodeLocal, {starTime: 0, endTime: 500}],
           [mainDocumentNodeLocal, {startTime: 500, endTime: 1000}],
           [scriptNodeLocal, {startTime: 1000, endTime: 2000}],
           [scriptAddedNodeLocal, {startTime: 2000, endTime: 3250}],
+          [scriptSubNodeLocal, {startTime: 2000, endTime: 3000}],
+          [scriptOtherNodeLocal, {startTime: 2000, endTime: 3500}],
         ]);
 
         if (scriptAddedNodeLocal.getDependencies()[0] === mainDocumentNodeLocal) {
           nodeTimings.set(scriptAddedNodeLocal, {startTime: 1000, endTime: 2000});
         }
 
-        return {timeInMs: 3250, nodeTimings};
+        if (scriptSubNodeLocal.getDependencies()[0] === mainDocumentNodeLocal) {
+          nodeTimings.set(scriptSubNodeLocal, {startTime: 1000, endTime: 2000});
+        }
+
+        if (scriptOtherNodeLocal.getDependencies()[0] === mainDocumentNodeLocal) {
+          nodeTimings.set(scriptOtherNodeLocal, {startTime: 1000, endTime: 2500});
+        }
+
+        return {timeInMs: 3500, nodeTimings};
       },
     };
 
@@ -92,17 +108,27 @@ describe('Performance: uses-rel-preload audit', () => {
       {
         requestId: '2',
         _isLinkPreload: false,
-        _url: 'http://www.example.com',
+        url: 'http://www.example.com',
       },
       {
         requestId: '3',
         _isLinkPreload: false,
-        _url: 'http://www.example.com/script.js',
+        url: 'http://www.example.com/script.js',
       },
       {
         requestId: '4',
         _isLinkPreload: false,
-        _url: 'http://www.example.com/script-added.js',
+        url: 'http://www.example.com/script-added.js',
+      },
+      {
+        requestId: '5',
+        _isLinkPreload: false,
+        url: 'http://sub.example.com/script-sub.js',
+      },
+      {
+        requestId: '6',
+        _isLinkPreload: false,
+        url: 'http://otherdomain.com/script-other.js',
       },
     ];
 
@@ -119,6 +145,14 @@ describe('Performance: uses-rel-preload audit', () => {
                     request: networkRecords[2],
                     children: {},
                   },
+                  '5': {
+                    request: networkRecords[3],
+                    children: {},
+                  },
+                  '6': {
+                    request: networkRecords[4],
+                    children: {},
+                  },
                 },
               },
             },
@@ -130,7 +164,7 @@ describe('Performance: uses-rel-preload audit', () => {
     return UsesRelPreload.audit(mockArtifacts(networkRecords, chains, mainResource), {}).then(
       output => {
         assert.equal(output.rawValue, 1250);
-        assert.equal(output.details.items.length, 1);
+        assert.equal(output.details.items.length, 2);
       }
     );
   });