Register qute:// scheme with Qt

See #3992, #4198

qutebrowser/browser/webengine/webenginequtescheme.py

@@ -22,6 +22,11 @@
 from PyQt5.QtCore import QBuffer, QIODevice, QUrl
 from PyQt5.QtWebEngineCore import (QWebEngineUrlSchemeHandler,
                                    QWebEngineUrlRequestJob)
+try:
+    from PyQt5.QtWebEngineCore import QWebEngineUrlScheme  # type: ignore
+except ImportError:
+    # Added in Qt 5.12
+    QWebEngineUrlScheme = None
 
 from qutebrowser.browser import qutescheme
 from qutebrowser.utils import log, qtutils
@@ -33,6 +38,9 @@ class QuteSchemeHandler(QWebEngineUrlSchemeHandler):
 
     def install(self, profile):
         """Install the handler for qute:// URLs on the given profile."""
+        if QWebEngineUrlScheme is not None:
+            assert QWebEngineUrlScheme.schemeByName(b'qute') is not None
+
         profile.installUrlSchemeHandler(b'qute', self)
         if (qtutils.version_check('5.11', compiled=False) and
                 not qtutils.version_check('5.12', compiled=False)):
@@ -131,3 +139,16 @@ class QuteSchemeHandler(QWebEngineUrlSchemeHandler):
             buf.seek(0)
             buf.close()
             job.reply(mimetype.encode('ascii'), buf)
+
+
+def init():
+    """Register the qute:// scheme.
+
+    Note this needs to be called early, before constructing any QtWebEngine
+    classes.
+    """
+    if QWebEngineUrlScheme is not None:
+        scheme = QWebEngineUrlScheme(b'qute')
+        scheme.setFlags(QWebEngineUrlScheme.LocalScheme |
+                        QWebEngineUrlScheme.LocalAccessAllowed)
+        QWebEngineUrlScheme.registerScheme(scheme)

qutebrowser/browser/webengine/webenginesettings.py

@@ -30,7 +30,7 @@ from PyQt5.QtGui import QFont
 from PyQt5.QtWebEngineWidgets import (QWebEngineSettings, QWebEngineProfile,
                                       QWebEnginePage)
 
-from qutebrowser.browser.webengine import spell
+from qutebrowser.browser.webengine import spell, webenginequtescheme
 from qutebrowser.config import config, websettings
 from qutebrowser.config.websettings import AttributeInfo as Attr
 from qutebrowser.utils import utils, standarddir, qtutils, message, log
@@ -298,6 +298,7 @@ def init(args):
             not hasattr(QWebEnginePage, 'setInspectedPage')):  # only Qt < 5.11
         os.environ['QTWEBENGINE_REMOTE_DEBUGGING'] = str(utils.random_port())
 
+    webenginequtescheme.init()
     spell.init()
 
     _init_profiles()