Bug 1788225 - Part 3: Check the site preference of the top-level domain when getting the cookie rule and clicking rule. r=pbz

The site preference will take precedence over the pref setting when we
getting the cookie rule and the clicking rule. We will use the top-level
uri to check the site preference which aligns with the behavior of ETP
toggle.

Differential Revision: https://phabricator.services.mozilla.com/D157869

toolkit/components/cookiebanners/CookieBannerParent.jsm

@@ -57,12 +57,42 @@ class CookieBannerParent extends JSWindowActorParent {
 
     // TODO: Bug 1790688: consider moving this logic to the cookie banner service.
     let mode;
-    if (this.#isPrivateBrowsing()) {
+    let isPrivateBrowsing = this.#isPrivateBrowsing();
+    if (isPrivateBrowsing) {
       mode = lazy.serviceModePBM;
     } else {
       mode = lazy.serviceMode;
     }
 
+    // Check if we have a site preference of the top-level URI. If so, it
+    // takes precedence over the pref setting.
+    let topBrowsingContext = this.manager.browsingContext.top;
+    let topURI = topBrowsingContext.currentWindowGlobal?.documentURI;
+
+    // We don't need to check the domain preference if the cookie banner
+    // handling was disabled by pref.
+    if (mode != Ci.nsICookieBannerService.MODE_DISABLED && topURI) {
+      try {
+        let perDomainMode = Services.cookieBanners.getDomainPref(
+          topURI,
+          isPrivateBrowsing
+        );
+
+        if (perDomainMode != Ci.nsICookieBannerService.MODE_UNSET) {
+          mode = perDomainMode;
+        }
+      } catch (e) {
+        // getPerSitePref could throw with NS_ERROR_NOT_AVAILABLE if the service
+        // is disabled. We will fallback to global pref setting if any errors
+        // occur.
+        if (e.result == Cr.NS_ERROR_NOT_AVAILABLE) {
+          Cu.reportError("The cookie banner handling service is not available");
+        } else {
+          Cu.reportError("Fail on getting domain pref:" + e);
+        }
+      }
+    }
+
     // Service is disabled for current context (normal or private browsing),
     // return empty array.
     if (mode == Ci.nsICookieBannerService.MODE_DISABLED) {

toolkit/components/cookiebanners/nsCookieBannerService.cpp

@@ -5,24 +5,25 @@
 #include "nsCookieBannerService.h"
 
 #include "CookieBannerDomainPrefService.h"
+#include "ErrorList.h"
+#include "mozilla/ClearOnShutdown.h"
+#include "mozilla/dom/CanonicalBrowsingContext.h"
+#include "mozilla/EventQueue.h"
+#include "mozilla/Logging.h"
+#include "mozilla/StaticPrefs_cookiebanners.h"
+#include "nsCOMPtr.h"
 #include "nsCookieBannerRule.h"
 #include "nsCookieInjector.h"
+#include "nsCRT.h"
+#include "nsDebug.h"
 #include "nsIClickRule.h"
 #include "nsICookieBannerListService.h"
 #include "nsICookieBannerRule.h"
 #include "nsICookie.h"
 #include "nsIEffectiveTLDService.h"
-#include "mozilla/StaticPrefs_cookiebanners.h"
-#include "ErrorList.h"
-#include "mozilla/Logging.h"
-#include "nsDebug.h"
-#include "nsCOMPtr.h"
 #include "nsNetCID.h"
 #include "nsServiceManagerUtils.h"
-#include "nsCRT.h"
-#include "mozilla/ClearOnShutdown.h"
 #include "nsThreadUtils.h"
-#include "mozilla/EventQueue.h"
 
 namespace mozilla {
 
@@ -287,8 +288,23 @@ nsCookieBannerService::GetCookiesForURI(
       gCookieBannerLog, LogLevel::Debug,
       ("%s. Found nsICookieBannerRule. Computed mode: %d", __FUNCTION__, mode));
 
-  // Service is disabled for current context (normal or private browsing),
-  // return empty array.
+  // We don't need to check the domain preference if the cookie banner handling
+  // service is disabled by pref.
+  if (mode != nsICookieBannerService::MODE_DISABLED) {
+    // Get the domain preference for the uri, the domain preference takes
+    // precedence over the pref setting. Note that the domain preference is
+    // supposed to stored only for top level URIs.
+    nsICookieBannerService::Modes domainPref;
+    nsresult rv = GetDomainPref(aURI, aIsPrivateBrowsing, &domainPref);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (domainPref != nsICookieBannerService::MODE_UNSET) {
+      mode = domainPref;
+    }
+  }
+
+  // Service is disabled for current context (normal, private browsing or domain
+  // preference), return empty array.
   if (mode == nsICookieBannerService::MODE_DISABLED) {
     MOZ_LOG(gCookieBannerLog, LogLevel::Debug,
             ("%s. Returning empty array. Got MODE_DISABLED for "