qutebrowser/qutebrowser/browser/webkit/webkitelem.py

366 lines
13 KiB
Python

# vim: ft=python fileencoding=utf-8 sts=4 sw=4 et:
# Copyright 2014-2018 Florian Bruhin (The Compiler) <mail@qutebrowser.org>
#
# This file is part of qutebrowser.
#
# qutebrowser is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# qutebrowser is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with qutebrowser. If not, see <http://www.gnu.org/licenses/>.
"""QtWebKit specific part of the web element API."""
from PyQt5.QtCore import QRect
from PyQt5.QtWebKit import QWebElement, QWebSettings
from qutebrowser.config import config
from qutebrowser.utils import log, utils, javascript
from qutebrowser.browser import webelem
class IsNullError(webelem.Error):
"""Gets raised by WebKitElement if an element is null."""
pass
class WebKitElement(webelem.AbstractWebElement):
"""A wrapper around a QWebElement."""
def __init__(self, elem, tab):
super().__init__(tab)
if isinstance(elem, self.__class__):
raise TypeError("Trying to wrap a wrapper!")
if elem.isNull():
raise IsNullError('{} is a null element!'.format(elem))
self._elem = elem
def __str__(self):
self._check_vanished()
return self._elem.toPlainText()
def __eq__(self, other):
if not isinstance(other, WebKitElement):
return NotImplemented
return self._elem == other._elem # pylint: disable=protected-access
def __getitem__(self, key):
self._check_vanished()
if key not in self:
raise KeyError(key)
return self._elem.attribute(key)
def __setitem__(self, key, val):
self._check_vanished()
self._elem.setAttribute(key, val)
def __delitem__(self, key):
self._check_vanished()
if key not in self:
raise KeyError(key)
self._elem.removeAttribute(key)
def __contains__(self, key):
self._check_vanished()
return self._elem.hasAttribute(key)
def __iter__(self):
self._check_vanished()
yield from self._elem.attributeNames()
def __len__(self):
self._check_vanished()
return len(self._elem.attributeNames())
def _check_vanished(self):
"""Raise an exception if the element vanished (is null)."""
if self._elem.isNull():
raise IsNullError('Element {} vanished!'.format(self._elem))
def has_frame(self):
self._check_vanished()
return self._elem.webFrame() is not None
def geometry(self):
self._check_vanished()
return self._elem.geometry()
def classes(self):
self._check_vanished()
return self._elem.classes()
def tag_name(self):
"""Get the tag name for the current element."""
self._check_vanished()
return self._elem.tagName().lower()
def outer_xml(self):
"""Get the full HTML representation of this element."""
self._check_vanished()
return self._elem.toOuterXml()
def value(self):
self._check_vanished()
val = self._elem.evaluateJavaScript('this.value')
assert isinstance(val, (int, float, str, type(None))), val
return val
def set_value(self, value):
self._check_vanished()
if self._tab.is_deleted():
raise webelem.OrphanedError("Tab containing element vanished")
if self.is_content_editable():
log.webelem.debug("Filling {!r} via set_text.".format(self))
self._elem.setPlainText(value)
else:
log.webelem.debug("Filling {!r} via javascript.".format(self))
value = javascript.string_escape(value)
self._elem.evaluateJavaScript("this.value='{}'".format(value))
def dispatch_event(self, event, bubbles=False,
cancelable=False, composed=False):
self._check_vanished()
log.webelem.debug("Firing event on {!r} via javascript.".format(self))
event = javascript.string_escape(event)
self._elem.evaluateJavaScript(
"this.dispatchEvent(new Event('{}', "
"{{'bubbles': {}, 'cancelable': {}, 'composed': {}}}))"
.format(event, str(bubbles).lower(), str(cancelable).lower(),
str(composed).lower()))
def caret_position(self):
"""Get the text caret position for the current element."""
self._check_vanished()
pos = self._elem.evaluateJavaScript('this.selectionStart')
if pos is None:
return 0
return int(pos)
def insert_text(self, text):
self._check_vanished()
if not self.is_editable(strict=True):
raise webelem.Error("Element is not editable!")
log.webelem.debug("Inserting text into element {!r}".format(self))
self._elem.evaluateJavaScript("""
var text = "{}";
var event = document.createEvent("TextEvent");
event.initTextEvent("textInput", true, true, null, text);
this.dispatchEvent(event);
""".format(javascript.string_escape(text)))
def _parent(self):
"""Get the parent element of this element."""
self._check_vanished()
elem = self._elem.parent()
if elem is None or elem.isNull():
return None
return WebKitElement(elem, tab=self._tab)
def _rect_on_view_js(self):
"""Javascript implementation for rect_on_view."""
# FIXME:qtwebengine maybe we can reuse this?
rects = self._elem.evaluateJavaScript("this.getClientRects()")
if rects is None: # pragma: no cover
# On e.g. Void Linux with musl libc, the stack size is too small
# for jsc, and running JS will fail. If that happens, fall back to
# the Python implementation.
# https://github.com/qutebrowser/qutebrowser/issues/1641
return None
text = utils.compact_text(self._elem.toOuterXml(), 500)
log.webelem.vdebug("Client rectangles of element '{}': {}".format(
text, rects))
for i in range(int(rects.get("length", 0))):
rect = rects[str(i)]
width = rect.get("width", 0)
height = rect.get("height", 0)
if width > 1 and height > 1:
# fix coordinates according to zoom level
zoom = self._elem.webFrame().zoomFactor()
if not config.val.zoom.text_only:
rect["left"] *= zoom
rect["top"] *= zoom
width *= zoom
height *= zoom
rect = QRect(rect["left"], rect["top"], width, height)
frame = self._elem.webFrame()
while frame is not None:
# Translate to parent frames' position (scroll position
# is taken care of inside getClientRects)
rect.translate(frame.geometry().topLeft())
frame = frame.parentFrame()
return rect
return None
def _rect_on_view_python(self, elem_geometry):
"""Python implementation for rect_on_view."""
if elem_geometry is None:
geometry = self._elem.geometry()
else:
geometry = elem_geometry
frame = self._elem.webFrame()
rect = QRect(geometry)
while frame is not None:
rect.translate(frame.geometry().topLeft())
rect.translate(frame.scrollPosition() * -1)
frame = frame.parentFrame()
return rect
def rect_on_view(self, *, elem_geometry=None, no_js=False):
"""Get the geometry of the element relative to the webview.
Uses the getClientRects() JavaScript method to obtain the collection of
rectangles containing the element and returns the first rectangle which
is large enough (larger than 1px times 1px). If all rectangles returned
by getClientRects() are too small, falls back to elem.rect_on_view().
Skipping of small rectangles is due to <a> elements containing other
elements with "display:block" style, see
https://github.com/qutebrowser/qutebrowser/issues/1298
Args:
elem_geometry: The geometry of the element, or None.
Calling QWebElement::geometry is rather expensive so
we want to avoid doing it twice.
no_js: Fall back to the Python implementation
"""
self._check_vanished()
# First try getting the element rect via JS, as that's usually more
# accurate
if elem_geometry is None and not no_js:
rect = self._rect_on_view_js()
if rect is not None:
return rect
# No suitable rects found via JS, try via the QWebElement API
return self._rect_on_view_python(elem_geometry)
def _is_visible(self, mainframe):
"""Check if the given element is visible in the given frame.
This is not public API because it can't be implemented easily here with
QtWebEngine, and is only used via find_css(..., only_visible=True) via
the tab API.
"""
self._check_vanished()
# CSS attributes which hide an element
hidden_attributes = {
'visibility': 'hidden',
'display': 'none',
'opacity': '0',
}
for k, v in hidden_attributes.items():
if (self._elem.styleProperty(k, QWebElement.ComputedStyle) == v and
'ace_text-input' not in self.classes()):
return False
elem_geometry = self._elem.geometry()
if not elem_geometry.isValid() and elem_geometry.x() == 0:
# Most likely an invisible link
return False
# First check if the element is visible on screen
elem_rect = self.rect_on_view(elem_geometry=elem_geometry)
mainframe_geometry = mainframe.geometry()
if elem_rect.isValid():
visible_on_screen = mainframe_geometry.intersects(elem_rect)
else:
# We got an invalid rectangle (width/height 0/0 probably), but this
# can still be a valid link.
visible_on_screen = mainframe_geometry.contains(
elem_rect.topLeft())
# Then check if it's visible in its frame if it's not in the main
# frame.
elem_frame = self._elem.webFrame()
framegeom = QRect(elem_frame.geometry())
if not framegeom.isValid():
visible_in_frame = False
elif elem_frame.parentFrame() is not None:
framegeom.moveTo(0, 0)
framegeom.translate(elem_frame.scrollPosition())
if elem_geometry.isValid():
visible_in_frame = framegeom.intersects(elem_geometry)
else:
# We got an invalid rectangle (width/height 0/0 probably), but
# this can still be a valid link.
visible_in_frame = framegeom.contains(elem_geometry.topLeft())
else:
visible_in_frame = visible_on_screen
return all([visible_on_screen, visible_in_frame])
def remove_blank_target(self):
elem = self
for _ in range(5):
if elem is None:
break
if elem.is_link():
if elem.get('target', None) == '_blank':
elem['target'] = '_top'
break
elem = elem._parent() # pylint: disable=protected-access
def _move_text_cursor(self):
if self.is_text_input() and self.is_editable():
self._tab.caret.move_to_end_of_document()
def _requires_user_interaction(self):
return False
def _click_editable(self, click_target):
ok = self._elem.evaluateJavaScript('this.focus(); true;')
if ok:
self._move_text_cursor()
else:
log.webelem.debug("Failed to focus via JS, falling back to event")
self._click_fake_event(click_target)
def _click_js(self, click_target):
settings = QWebSettings.globalSettings()
attribute = QWebSettings.JavascriptCanOpenWindows
could_open_windows = settings.testAttribute(attribute)
settings.setAttribute(attribute, True)
ok = self._elem.evaluateJavaScript('this.click(); true;')
settings.setAttribute(attribute, could_open_windows)
if not ok:
log.webelem.debug("Failed to click via JS, falling back to event")
self._click_fake_event(click_target)
def _click_fake_event(self, click_target):
self._tab.data.override_target = click_target
super()._click_fake_event(click_target)
def get_child_frames(startframe):
"""Get all children recursively of a given QWebFrame.
Loosely based on http://blog.nextgenetics.net/?e=64
Args:
startframe: The QWebFrame to start with.
Return:
A list of children QWebFrame, or an empty list.
"""
results = []
frames = [startframe]
while frames:
new_frames = []
for frame in frames:
results.append(frame)
new_frames += frame.childFrames()
frames = new_frames
return results