Serve broken qutebrowser logo via qute:resources

This is needed when we want to display an error page after the user
requested a qute:// URL, as qute:// URLs can't access file:// content
with QtWebEngine.

qutebrowser/browser/qutescheme.py

@@ -24,6 +24,7 @@ Module attributes:
     _HANDLERS: The handlers registered via decorators.
 """
 
+import mimetypes
 import urllib.parse
 
 import qutebrowser
@@ -102,7 +103,7 @@ class add_handler:  # pylint: disable=invalid-name
                             url=url.toDisplayString(),
                             error='{} is not available with this '
                                   'backend'.format(url.toDisplayString()),
-                            icon='')
+                            icon='', qutescheme=True)
         return 'text/html', html
 
 
@@ -237,7 +238,8 @@ def qute_help(url):
                   "repository, please run scripts/asciidoc2html.py. "
                   "If you're running a released version this is a bug, please "
                   "use :report to report it.",
-            icon='')
+            icon='',
+            qutescheme=True)
         return 'text/html', html
     urlpath = url.path()
     if not urlpath or urlpath == '/':
@@ -253,3 +255,11 @@ def qute_help(url):
     else:
         data = utils.read_file(path)
         return 'text/html', data
+
+
+@add_handler('resource')
+def qute_resource(url):
+    data = utils.read_file(url.path(), binary=True)
+    mimetype, _encoding = mimetypes.guess_type(url.fileName())
+    assert mimetype is not None, url
+    return mimetype, data

qutebrowser/browser/webkit/network/filescheme.py

@@ -102,7 +102,7 @@ def dirbrowser_html(path):
         html = jinja.render('error.html',
                             title="Error while reading directory",
                             url='file:///{}'.format(path), error=str(e),
-                            icon='')
+                            icon='', qutescheme=False)
         return html.encode('UTF-8', errors='xmlcharrefreplace')
 
     files = get_file_list(path, all_files, os.path.isfile)

qutebrowser/browser/webkit/webpage.py

@@ -170,7 +170,8 @@ class BrowserPage(QWebPage):
             title = "Error loading page: {}".format(urlstr)
             html = jinja.render(
                 'error.html',
-                title=title, url=urlstr, error=error_str, icon='')
+                title=title, url=urlstr, error=error_str, icon='',
+                qutescheme=False)
             errpage.content = html.encode('utf-8')
             errpage.encoding = 'utf-8'
             return True

qutebrowser/html/error.html

@@ -73,7 +73,7 @@ function searchFor(uri) {
 	<table>
 		<tr>
 			<td style="width: 10%; vertical-align: top;">
-				<img style="width: 100%; display: block; max-width: 256px;" src="{{ resource_url('img/broken_qutebrowser_logo.png') }}" />
+				<img style="width: 100%; display: block; max-width: 256px;" src="{{ resource_url('img/broken_qutebrowser_logo.png', qutescheme) }}" />
 			</td>
 			<td style="padding-left: 40px;">
 				<h1>Unable to load page</h1>

qutebrowser/utils/jinja.py

@@ -26,7 +26,7 @@ import traceback
 import jinja2
 import jinja2.exceptions
 
-from qutebrowser.utils import utils, urlutils, log
+from qutebrowser.utils import utils, urlutils, log, qtutils
 
 from PyQt5.QtCore import QUrl
 
@@ -64,14 +64,25 @@ def _guess_autoescape(template_name):
     return ext in ['html', 'htm', 'xml']
 
 
-def resource_url(path):
+def resource_url(path, qutescheme):
     """Load images from a relative path (to qutebrowser).
 
     Arguments:
         path: The relative path to the image
+        qutescheme: If the logo needs to be served via a qute:// scheme.
+                    This is the case when we want to show an error page from
+                    there.
     """
-    image = utils.resource_filename(path)
+    if qutescheme:
-    return QUrl.fromLocalFile(image).toString(QUrl.FullyEncoded)
+        url = QUrl()
+        url.setScheme('qute')
+        url.setHost('resource')
+        url.setPath('/' + path)
+        qtutils.ensure_valid(url)
+        return url.toString(QUrl.FullyEncoded)
+    else:
+        full_path = utils.resource_filename(path)
+        return QUrl.fromLocalFile(full_path).toString(QUrl.FullyEncoded)
 
 
 def render(template, **kwargs):

tests/unit/utils/test_jinja.py

@@ -39,8 +39,10 @@ def patch_read_file(monkeypatch):
         """A read_file which returns a simple template if the path is right."""
         if path == os.path.join('html', 'test.html'):
             return """Hello {{var}}"""
-        elif path == os.path.join('html', 'test2.html'):
+        elif path == os.path.join('html', 'resource_url.html'):
-            return """{{ resource_url('utils/testfile') }}"""
+            return """{{ resource_url('utils/testfile', False) }}"""
+        elif path == os.path.join('html', 'resource_url_qute.html'):
+            return """{{ resource_url('utils/testfile', True) }}"""
         elif path == os.path.join('html', 'undef.html'):
             return """{{ does_not_exist() }}"""
         elif path == os.path.join('html', 'undef_error.html'):
@@ -59,7 +61,7 @@ def test_simple_template():
 
 def test_resource_url():
     """Test resource_url() which can be used from templates."""
-    data = jinja.render('test2.html')
+    data = jinja.render('resource_url.html')
     print(data)
     url = QUrl(data)
     assert url.isValid()
@@ -75,6 +77,14 @@ def test_resource_url():
         assert f.read().splitlines()[0] == "Hello World!"
 
 
+def test_resource_url_qutescheme():
+    """Test resource_url() which can be used from templates."""
+    data = jinja.render('resource_url_qute.html')
+    print(data)
+    url = QUrl(data)
+    assert url == QUrl('qute://resource/utils/testfile')
+
+
 def test_not_found():
     """Test with a template which does not exist."""
     with pytest.raises(jinja2.TemplateNotFound) as excinfo: