make the host_blocker aware of patterns

Add an additional argument to is_blocked for the current url, and enable
the host_blocking.enabled property to be set per domain.
This allows to bypass host blocking for specific domains

qutebrowser/browser/adblock.py

@@ -111,9 +111,10 @@ class HostBlocker:
 
         config.instance.changed.connect(self._update_files)
 
-    def is_blocked(self, url):
+    def is_blocked(self, url, first_party_url=None):
         """Check if the given URL (as QUrl) is blocked."""
-        if not config.val.content.host_blocking.enabled:
+        if not config.instance.get('content.host_blocking.enabled',
+                                   url=first_party_url):
             return False
         host = url.host()
         return ((host in self._blocked_hosts or

qutebrowser/browser/webengine/interceptor.py

@@ -69,9 +69,10 @@ class RequestInterceptor(QWebEngineUrlRequestInterceptor):
                                   resource_type, navigation_type))
 
         url = info.requestUrl()
+        first_party = info.firstPartyUrl()
 
         # FIXME:qtwebengine only block ads for NavigationTypeOther?
-        if self._host_blocker.is_blocked(url):
+        if self._host_blocker.is_blocked(url, first_party):
             log.webview.info("Request to {} blocked by host blocker.".format(
                 url.host()))
             info.block(True)

qutebrowser/browser/webkit/network/networkmanager.py

@@ -383,14 +383,6 @@ class NetworkManager(QNetworkAccessManager):
         for header, value in shared.custom_headers(url=req.url()):
             req.setRawHeader(header, value)
 
-        host_blocker = objreg.get('host-blocker')
-        if host_blocker.is_blocked(req.url()):
-            log.webview.info("Request to {} blocked by host blocker.".format(
-                req.url().host()))
-            return networkreply.ErrorNetworkReply(
-                req, HOSTBLOCK_ERROR_STRING, QNetworkReply.ContentAccessDenied,
-                self)
-
         # There are some scenarios where we can't figure out current_url:
         # - There's a generic NetworkManager, e.g. for downloads
         # - The download was in a tab which is now closed.
@@ -408,6 +400,14 @@ class NetworkManager(QNetworkAccessManager):
                 # the webpage shutdown here.
                 current_url = QUrl()
 
+        host_blocker = objreg.get('host-blocker')
+        if host_blocker.is_blocked(req.url(), current_url):
+            log.webview.info("Request to {} blocked by host blocker.".format(
+                req.url().host()))
+            return networkreply.ErrorNetworkReply(
+                req, HOSTBLOCK_ERROR_STRING, QNetworkReply.ContentAccessDenied,
+                self)
+
         if 'log-requests' in self._args.debug_flags:
             operation = debug.qenum_key(QNetworkAccessManager, op)
             operation = operation.replace('Operation', '').upper()

qutebrowser/config/configdata.yml

@@ -467,6 +467,7 @@ content.headers.user_agent:
 
 content.host_blocking.enabled:
   default: true
+  supports_pattern: true
   type: Bool
   desc: Enable host blocking.