Fix #511: Youtube intermittent ads (#2655)

Client.xcodeproj/project.pbxproj

@@ -709,6 +709,7 @@
 		5E46C37C234FB9A700ACA8C1 /* self-signed.cer in Resources */ = {isa = PBXBuildFile; fileRef = 5E46C37B234FB9A700ACA8C1 /* self-signed.cer */; };
 		5E4845C022DE381200372022 /* WindowRenderHelper.js in Resources */ = {isa = PBXBuildFile; fileRef = 5E4845BF22DE381200372022 /* WindowRenderHelper.js */; };
 		5E4845C222DE3DF800372022 /* WindowRenderHelperScript.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5E4845C122DE3DF800372022 /* WindowRenderHelperScript.swift */; };
+		5E4E078324A0E4D700B01720 /* YoutubeAdblock.js in Resources */ = {isa = PBXBuildFile; fileRef = 5E4E078224A0E4D700B01720 /* YoutubeAdblock.js */; };
 		5E612A8C234B7FC1007D12B5 /* OnboardingAdsAvailableController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5E1D8C66232BE43100BDE662 /* OnboardingAdsAvailableController.swift */; };
 		5E612A8E234B7FC8007D12B5 /* OnboardingAdsAvailableView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5E1D8C68232BE47A00BDE662 /* OnboardingAdsAvailableView.swift */; };
 		5E612A8F234B7FCA007D12B5 /* OnboardingRewardsAgreementViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5E1D8C6A232BF95200BDE662 /* OnboardingRewardsAgreementViewController.swift */; };
@@ -2223,6 +2224,7 @@
 		5E46C37B234FB9A700ACA8C1 /* self-signed.cer */ = {isa = PBXFileReference; lastKnownFileType = file; path = "self-signed.cer"; sourceTree = "<group>"; };
 		5E4845BF22DE381200372022 /* WindowRenderHelper.js */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.javascript; path = WindowRenderHelper.js; sourceTree = "<group>"; };
 		5E4845C122DE3DF800372022 /* WindowRenderHelperScript.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WindowRenderHelperScript.swift; sourceTree = "<group>"; };
+		5E4E078224A0E4D700B01720 /* YoutubeAdblock.js */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.javascript; path = YoutubeAdblock.js; sourceTree = "<group>"; };
 		5E6683A823D61CF7005B3A6C /* NTPDownloader.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NTPDownloader.swift; sourceTree = "<group>"; };
 		5E77F9DC236BB68700E1649C /* AttestationDebugger.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AttestationDebugger.swift; sourceTree = "<group>"; };
 		5E856FE5235E08110094E113 /* Cryptography.swift */ = {isa = PBXFileReference; indentWidth = 2; lastKnownFileType = sourcecode.swift; path = Cryptography.swift; sourceTree = "<group>"; tabWidth = 2; };
@@ -4475,6 +4477,7 @@
 				5E4845BF22DE381200372022 /* WindowRenderHelper.js */,
 				5EB57D0122FDC0CB00A07325 /* FullscreenHelper.js */,
 				F9B23EE123F61173000EB3D8 /* PaymentRequest.js */,
+				5E4E078224A0E4D700B01720 /* YoutubeAdblock.js */,
 			);
 			path = UserScripts;
 			sourceTree = "<group>";
@@ -5872,6 +5875,7 @@
 				E4B7B7861A793CF20022C5E0 /* FiraSans-UltraLight.ttf in Resources */,
 				E4B7B77D1A793CF20022C5E0 /* FiraSans-Regular.ttf in Resources */,
 				4422D55221BFFB7E00BF1855 /* make_unicode_casefold.py in Resources */,
+				5E4E078324A0E4D700B01720 /* YoutubeAdblock.js in Resources */,
 				E4B7B7791A793CF20022C5E0 /* FiraSans-Light.ttf in Resources */,
 				5E3477E922D7771700B0D5F8 /* ResourceDownloader.js in Resources */,
 				F99505FF22937E3900CC6543 /* U2F-low-level.js in Resources */,

Client/Frontend/Browser/BrowserViewController/BrowserViewController+WKNavigationDelegate.swift

@@ -188,7 +188,14 @@ extension BrowserViewController: WKNavigationDelegate {
             decisionHandler(.cancel)
             return
         }
+
         let isPrivateBrowsing = PrivateBrowsingManager.shared.isPrivateBrowsing
+
+        if url.baseDomain == "youtube.com" {
+            let domain = Domain.getOrCreate(forUrl: url, persistent: !isPrivateBrowsing)
+            tabManager[webView]?.userScriptManager?.isYoutubeAdblockEnabled = domain.isShieldExpected(.AdblockAndTp, considerAllShieldsOption: true)
+        }
+
         // This is the normal case, opening a http or https url, which we handle by loading them in this WKWebView. We
         // always allow this. Additionally, data URIs are also handled just like normal web pages.
 

Client/Frontend/Browser/Tab.swift

@@ -242,7 +242,8 @@ class Tab: NSObject {
                 isFingerprintingProtectionEnabled: Preferences.Shields.fingerprintingProtection.value,
                 isCookieBlockingEnabled: Preferences.Privacy.blockAllCookies.value,
                 isU2FEnabled: webView.hasOnlySecureContent,
-                isPaymentRequestEnabled: webView.hasOnlySecureContent)
+                isPaymentRequestEnabled: webView.hasOnlySecureContent,
+                isYoutubeAdblockEnabled: false)
             tabDelegate?.tab?(self, didCreateWebView: webView)
         }
     }

Client/Frontend/Browser/UserScriptManager.swift

@@ -45,12 +45,21 @@ class UserScriptManager {
         }
     }
 
-    init(tab: Tab, isFingerprintingProtectionEnabled: Bool, isCookieBlockingEnabled: Bool, isU2FEnabled: Bool, isPaymentRequestEnabled: Bool) {
+    // Whether or not the Adblock shields are enabled
+    var isYoutubeAdblockEnabled: Bool {
+        didSet {
+            if oldValue == isYoutubeAdblockEnabled { return }
+            reloadUserScripts()
+        }
+    }
+
+    init(tab: Tab, isFingerprintingProtectionEnabled: Bool, isCookieBlockingEnabled: Bool, isU2FEnabled: Bool, isPaymentRequestEnabled: Bool, isYoutubeAdblockEnabled: Bool) {
         self.tab = tab
         self.isFingerprintingProtectionEnabled = isFingerprintingProtectionEnabled
         self.isCookieBlockingEnabled = isCookieBlockingEnabled
         self.isU2FEnabled = isU2FEnabled
         self.isPaymentRequestEnabled = isPaymentRequestEnabled
+        self.isYoutubeAdblockEnabled = isYoutubeAdblockEnabled
         reloadUserScripts()
     }
 
@@ -187,7 +196,7 @@ class UserScriptManager {
 
         //Verify that the application itself is making a call to the JS script instead of other scripts on the page.
         //This variable will be unique amongst scripts loaded in the page.
-        //When the script is called, the token is provided in order to access teh script variable.
+        //When the script is called, the token is provided in order to access the script variable.
         var alteredSource = source
         let token = UserScriptManager.securityToken.uuidString.replacingOccurrences(of: "-", with: "", options: .literal)
         alteredSource = alteredSource.replacingOccurrences(of: "$<possiblySupportedFunctions>", with: "PSF\(token)", options: .literal)
@@ -197,6 +206,23 @@ class UserScriptManager {
 
         return WKUserScript(source: alteredSource, injectionTime: .atDocumentStart, forMainFrameOnly: false)
     }()
+
+    private let youtubeAdblockJSScript: WKUserScript? = {
+        guard let path = Bundle.main.path(forResource: "YoutubeAdblock", ofType: "js"), let source = try? String(contentsOfFile: path) else {
+            log.error("Failed to load YoutubeAdblock.js")
+            return nil
+        }
+
+        //Verify that the application itself is making a call to the JS script instead of other scripts on the page.
+        //This variable will be unique amongst scripts loaded in the page.
+        //When the script is called, the token is provided in order to access the script variable.
+        var alteredSource = source
+        let token = UserScriptManager.securityToken.uuidString.replacingOccurrences(of: "-", with: "", options: .literal)
+        alteredSource = alteredSource.replacingOccurrences(of: "$<prunePaths>", with: "ABS\(token)", options: .literal)
+        alteredSource = alteredSource.replacingOccurrences(of: "$<findOwner>", with: "ABS\(token)", options: .literal)
+
+        return WKUserScript(source: alteredSource, injectionTime: .atDocumentStart, forMainFrameOnly: false)
+    }()
 
     private func reloadUserScripts() {
         tab?.webView?.configuration.userContentController.do {
@@ -230,6 +256,10 @@ class UserScriptManager {
                 $0.addUserScript(script)
             }
 
+            if isYoutubeAdblockEnabled, let script = youtubeAdblockJSScript {
+                $0.addUserScript(script)
+            }
+
             #if !NO_SKUS
             if isPaymentRequestEnabled, let script = PaymentRequestUserScript {
                 $0.addUserScript(script)

Client/Frontend/UserContent/UserScripts/YoutubeAdblock.js

@@ -0,0 +1,36 @@
+// Copyright 2020 The Brave Authors. All rights reserved.
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+(function() {
+    const $<prunePaths> = ['playerResponse.adPlacements', 'playerResponse.playerAds', 'adPlacements', 'playerAds'];
+    const $<findOwner> = function(root, path) {
+        let owner = root;
+        let chain = path;
+        while(true) {
+            if (owner instanceof Object === false) { return; }
+            const pos = chain.indexOf('.');
+            if (pos === -1) {
+                return owner.hasOwnProperty(chain)? [owner, chain]: undefined;
+            }
+            const prop = chain.slice(0, pos);
+            if (owner.hasOwnProperty(prop) === false) { return; }
+            owner = owner[prop];
+            chain = chain.slice(pos + 1);
+        }
+    };
+
+    JSON.parse = new Proxy(JSON.parse, {
+        apply: function() {
+            const r = Reflect.apply(...arguments);
+            for (const path of $<prunePaths>) {
+                const details = $<findOwner>(r, path);
+                if (details !== undefined) {
+                    delete details[0][details[1]];
+                }
+            }
+            return r;
+        },
+    });
+})();