eric: comparison eric6/UI/Previewers/PreviewerHTML.py

-:7926553b7509
+:8b8cadf8d7e9
+# -*- coding: utf-8 -*-
+# Copyright (c) 2014 - 2019 Detlev Offenbach <detlev@die-offenbachs.de>
+#
+"""
+Module implementing a previewer widget for HTML, Markdown and ReST files.
+"""
+from __future__ import unicode_literals
+try:  # Only for Py2
+import StringIO as io   # __IGNORE_EXCEPTION__
+str = unicode
+except (ImportError, NameError):
+import io       # __IGNORE_WARNING__
+import os
+import threading
+import re
+import shutil
+import tempfile
+import sys
+from PyQt5.QtCore import pyqtSlot, pyqtSignal, Qt, QUrl, QSize, QThread
+from PyQt5.QtGui import QCursor
+from PyQt5.QtWidgets import QWidget, QVBoxLayout, QLabel, QCheckBox, \
+QSizePolicy, QToolTip
+from E5Gui.E5Application import e5App
+import Utilities
+import Preferences
+class PreviewerHTML(QWidget):
+"""
+Class implementing a previewer widget for HTML, Markdown and ReST files.
+"""
+def __init__(self, parent=None):
+"""
+Constructor
+@param parent reference to the parent widget (QWidget)
+"""
+super(PreviewerHTML, self).__init__(parent)
+self.__layout = QVBoxLayout(self)
+self.titleLabel = QLabel(self)
+self.titleLabel.setWordWrap(True)
+self.titleLabel.setTextInteractionFlags(Qt.NoTextInteraction)
+self.__layout.addWidget(self.titleLabel)
+self.__previewAvailable = True
+try:
+from PyQt5.QtWebEngineWidgets import QWebEngineView
+self.previewView = QWebEngineView(self)
+self.previewView.page().linkHovered.connect(self.__showLink)
+self.__usesWebKit = False
+except ImportError:
+try:
+from PyQt5.QtWebKitWidgets import QWebPage, QWebView
+self.previewView = QWebView(self)
+self.previewView.page().setLinkDelegationPolicy(
+QWebPage.DelegateAllLinks)
+self.__usesWebKit = True
+except ImportError:
+self.__previewAvailable = False
+self.titleLabel.setText(self.tr(
+"<b>HTML Preview is not available!<br/>"
+"Install QtWebEngine or QtWebKit.</b>"))
+self.titleLabel.setAlignment(Qt.AlignHCenter)
+self.__layout.addStretch()
+return
+sizePolicy = QSizePolicy(QSizePolicy.Preferred, QSizePolicy.Expanding)
+sizePolicy.setHorizontalStretch(0)
+sizePolicy.setVerticalStretch(0)
+sizePolicy.setHeightForWidth(
+self.previewView.sizePolicy().hasHeightForWidth())
+self.previewView.setSizePolicy(sizePolicy)
+self.previewView.setContextMenuPolicy(Qt.NoContextMenu)
+self.previewView.setUrl(QUrl("about:blank"))
+self.__layout.addWidget(self.previewView)
+self.jsCheckBox = QCheckBox(self.tr("Enable JavaScript"), self)
+self.jsCheckBox.setToolTip(self.tr(
+"Select to enable JavaScript for HTML previews"))
+self.__layout.addWidget(self.jsCheckBox)
+self.ssiCheckBox = QCheckBox(self.tr("Enable Server Side Includes"),
+self)
+self.ssiCheckBox.setToolTip(self.tr(
+"Select to enable support for Server Side Includes"))
+self.__layout.addWidget(self.ssiCheckBox)
+self.jsCheckBox.clicked[bool].connect(self.on_jsCheckBox_clicked)
+self.ssiCheckBox.clicked[bool].connect(self.on_ssiCheckBox_clicked)
+self.previewView.titleChanged.connect(self.on_previewView_titleChanged)
+if self.__usesWebKit:
+self.previewView.linkClicked.connect(
+self.on_previewView_linkClicked)
+self.jsCheckBox.setChecked(
+Preferences.getUI("ShowFilePreviewJS"))
+self.ssiCheckBox.setChecked(
+Preferences.getUI("ShowFilePreviewSSI"))
+self.__scrollBarPositions = {}
+self.__vScrollBarAtEnd = {}
+self.__hScrollBarAtEnd = {}
+self.__processingThread = PreviewProcessingThread()
+self.__processingThread.htmlReady.connect(self.__setHtml)
+self.__previewedPath = None
+self.__previewedEditor = None
+def shutdown(self):
+"""
+Public method to perform shutdown actions.
+"""
+if self.__previewAvailable:
+self.__processingThread.wait()
+@pyqtSlot(bool)
+def on_jsCheckBox_clicked(self, checked):
+"""
+Private slot to enable/disable JavaScript.
+@param checked state of the checkbox (boolean)
+"""
+Preferences.setUI("ShowFilePreviewJS", checked)
+self.__setJavaScriptEnabled(checked)
+def __setJavaScriptEnabled(self, enable):
+"""
+Private method to enable/disable JavaScript.
+@param enable flag indicating the enable state (boolean)
+"""
+self.jsCheckBox.setChecked(enable)
+settings = self.previewView.settings()
+settings.setAttribute(settings.JavascriptEnabled, enable)
+self.processEditor()
+@pyqtSlot(bool)
+def on_ssiCheckBox_clicked(self, checked):
+"""
+Private slot to enable/disable SSI.
+@param checked state of the checkbox (boolean)
+"""
+Preferences.setUI("ShowFilePreviewSSI", checked)
+self.processEditor()
+@pyqtSlot(str)
+def __showLink(self, urlStr):
+"""
+Private slot to show the hovered link in a tooltip.
+@param urlStr hovered URL
+@type str
+"""
+QToolTip.showText(QCursor.pos(), urlStr, self.previewView)
+def processEditor(self, editor=None):
+"""
+Public slot to process an editor's text.
+@param editor editor to be processed (Editor)
+"""
+if not self.__previewAvailable:
+return
+if editor is None:
+editor = self.__previewedEditor
+else:
+self.__previewedEditor = editor
+if editor is not None:
+fn = editor.getFileName()
+if fn:
+extension = os.path.normcase(os.path.splitext(fn)[1][1:])
+else:
+extension = ""
+if extension in \
+Preferences.getEditor("PreviewHtmlFileNameExtensions") or \
+editor.getLanguage() == "HTML":
+language = "HTML"
+elif extension in \
+Preferences.getEditor("PreviewMarkdownFileNameExtensions") or \
+editor.getLanguage().lower() == "markdown":
+language = "Markdown"
+elif extension in \
+Preferences.getEditor("PreviewRestFileNameExtensions") or \
+editor.getLanguage().lower() == "restructuredtext":
+language = "ReST"
+else:
+self.__setHtml(fn, self.tr(
+"<p>No preview available for this type of file.</p>"))
+return
+if fn:
+project = e5App().getObject("Project")
+if project.isProjectFile(fn):
+rootPath = project.getProjectPath()
+else:
+rootPath = os.path.dirname(os.path.abspath(fn))
+else:
+rootPath = ""
+if bool(editor.text()):
+self.__processingThread.process(
+fn, language, editor.text(),
+self.ssiCheckBox.isChecked(), rootPath,
+Preferences.getEditor("PreviewRestUseSphinx"),
+Preferences.getEditor("PreviewMarkdownNLtoBR"),
+Preferences.getEditor("PreviewMarkdownHTMLFormat"),
+Preferences.getEditor("PreviewRestDocutilsHTMLFormat"))
+def __setHtml(self, filePath, html, rootPath):
+"""
+Private method to set the HTML to the view and restore the scroll bars
+positions.
+@param filePath file path of the previewed editor
+@type str
+@param html processed HTML text ready to be shown
+@type str
+@param rootPath path of the web site root
+@type str
+"""
+self.__previewedPath = Utilities.normcasepath(
+Utilities.fromNativeSeparators(filePath))
+self.__saveScrollBarPositions()
+if self.__usesWebKit:
+self.previewView.page().mainFrame().contentsSizeChanged.connect(
+self.__restoreScrollBarPositions)
+else:
+self.previewView.page().loadFinished.connect(
+self.__restoreScrollBarPositions)
+if not filePath:
+filePath = "/"
+if rootPath:
+baseUrl = QUrl.fromLocalFile(rootPath + "/index.html")
+else:
+baseUrl = QUrl.fromLocalFile(filePath)
+self.previewView.setHtml(html, baseUrl=baseUrl)
+if self.__previewedEditor:
+self.__previewedEditor.setFocus()
+@pyqtSlot(str)
+def on_previewView_titleChanged(self, title):
+"""
+Private slot to handle a change of the title.
+@param title new title (string)
+"""
+if title:
+self.titleLabel.setText(self.tr("Preview - {0}").format(title))
+else:
+self.titleLabel.setText(self.tr("Preview"))
+def __saveScrollBarPositions(self):
+"""
+Private method to save scroll bar positions for a previewed editor.
+"""
+if self.__usesWebKit:
+frame = self.previewView.page().mainFrame()
+if frame.contentsSize() == QSize(0, 0):
+return  # no valid data, nothing to save
+pos = frame.scrollPosition()
+self.__scrollBarPositions[self.__previewedPath] = pos
+self.__hScrollBarAtEnd[self.__previewedPath] = \
+frame.scrollBarMaximum(Qt.Horizontal) == pos.x()
+self.__vScrollBarAtEnd[self.__previewedPath] = \
+frame.scrollBarMaximum(Qt.Vertical) == pos.y()
+else:
+from PyQt5.QtCore import QPoint
+try:
+pos = self.previewView.scrollPosition()
+except AttributeError:
+pos = self.__execJavaScript(
+"(function() {"
+"var res = {"
+"    x: 0,"
+"    y: 0,"
+"};"
+"res.x = window.scrollX;"
+"res.y = window.scrollY;"
+"return res;"
+"})()"
+)
+if pos is not None:
+pos = QPoint(pos["x"], pos["y"])
+else:
+pos = QPoint(0, 0)
+self.__scrollBarPositions[self.__previewedPath] = pos
+self.__hScrollBarAtEnd[self.__previewedPath] = False
+self.__vScrollBarAtEnd[self.__previewedPath] = False
+def __restoreScrollBarPositions(self):
+"""
+Private method to restore scroll bar positions for a previewed editor.
+"""
+if self.__usesWebKit:
+try:
+self.previewView.page().mainFrame().contentsSizeChanged.\
+disconnect(self.__restoreScrollBarPositions)
+except TypeError:
+# not connected, simply ignore it
+pass
+if self.__previewedPath not in self.__scrollBarPositions:
+return
+frame = self.previewView.page().mainFrame()
+frame.setScrollPosition(
+self.__scrollBarPositions[self.__previewedPath])
+if self.__hScrollBarAtEnd[self.__previewedPath]:
+frame.setScrollBarValue(
+Qt.Horizontal, frame.scrollBarMaximum(Qt.Horizontal))
+if self.__vScrollBarAtEnd[self.__previewedPath]:
+frame.setScrollBarValue(
+Qt.Vertical, frame.scrollBarMaximum(Qt.Vertical))
+else:
+if self.__previewedPath not in self.__scrollBarPositions:
+return
+pos = self.__scrollBarPositions[self.__previewedPath]
+self.previewView.page().runJavaScript(
+"window.scrollTo({0}, {1});".format(pos.x(), pos.y()))
+@pyqtSlot(QUrl)
+def on_previewView_linkClicked(self, url):
+"""
+Private slot handling the clicking of a link.
+@param url URL of the clicked link
+@type QUrl
+"""
+e5App().getObject("UserInterface").launchHelpViewer(url)
+def __execJavaScript(self, script):
+"""
+Private function to execute a JavaScript function Synchroneously.
+@param script JavaScript script source to be executed
+@type str
+@return result of the script
+@rtype depending upon script result
+"""
+from PyQt5.QtCore import QEventLoop
+loop = QEventLoop()
+resultDict = {"res": None}
+def resultCallback(res, resDict=resultDict):
+if loop and loop.isRunning():
+resDict["res"] = res
+loop.quit()
+self.previewView.page().runJavaScript(
+script, resultCallback)
+loop.exec_()
+return resultDict["res"]
+class PreviewProcessingThread(QThread):
+"""
+Class implementing a thread to process some text into HTML usable by the
+previewer view.
+@signal htmlReady(str, str, str) emitted with the file name, the processed
+HTML and the web site root path to signal the availability of the
+processed HTML
+"""
+htmlReady = pyqtSignal(str, str, str)
+def __init__(self, parent=None):
+"""
+Constructor
+@param parent reference to the parent object (QObject)
+"""
+super(PreviewProcessingThread, self).__init__()
+self.__lock = threading.Lock()
+def process(self, filePath, language, text, ssiEnabled, rootPath,
+useSphinx, convertNewLineToBreak, markdownHtmlFormat,
+restDocutilsHtmlFormat):
+"""
+Public method to convert the given text to HTML.
+@param filePath file path of the text (string)
+@param language language of the text (string)
+@param text text to be processed (string)
+@param ssiEnabled flag indicating to do some (limited) SSI processing
+(boolean)
+@param rootPath root path to be used for SSI processing (str)
+@param useSphinx flag indicating to use Sphinx to generate the
+ReST preview (boolean)
+@param convertNewLineToBreak flag indicating to convert new lines
+to HTML break (Markdown only) (boolean)
+@param markdownHtmlFormat HTML format to be generated by markdown
+(string)
+@param restDocutilsHtmlFormat HTML format to be generated by docutils
+(string)
+"""
+with self.__lock:
+self.__filePath = filePath
+self.__language = language
+self.__text = text
+self.__ssiEnabled = ssiEnabled
+self.__rootPath = rootPath
+self.__haveData = True
+self.__useSphinx = useSphinx
+self.__convertNewLineToBreak = convertNewLineToBreak
+self.__markdownHtmlFormat = markdownHtmlFormat
+self.__restDocutilsHtmlFormat = restDocutilsHtmlFormat
+if not self.isRunning():
+self.start(QThread.LowPriority)
+def run(self):
+"""
+Public thread method to convert the stored data.
+"""
+while True:
+# exits with break
+with self.__lock:
+filePath = self.__filePath
+language = self.__language
+text = self.__text
+ssiEnabled = self.__ssiEnabled
+rootPath = self.__rootPath
+useSphinx = self.__useSphinx
+convertNewLineToBreak = self.__convertNewLineToBreak
+markdownHtmlFormat = self.__markdownHtmlFormat
+restDocutilsHtmlFormat = self.__restDocutilsHtmlFormat
+self.__haveData = False
+html = self.__getHtml(language, text, ssiEnabled, filePath,
+rootPath, useSphinx, convertNewLineToBreak,
+markdownHtmlFormat, restDocutilsHtmlFormat)
+with self.__lock:
+if not self.__haveData:
+self.htmlReady.emit(filePath, html, rootPath)
+break
+# else - next iteration
+def __getHtml(self, language, text, ssiEnabled, filePath, rootPath,
+useSphinx, convertNewLineToBreak, markdownHtmlFormat,
+restDocutilsHtmlFormat):
+"""
+Private method to process the given text depending upon the given
+language.
+@param language language of the text (string)
+@param text to be processed (string)
+@param ssiEnabled flag indicating to do some (limited) SSI processing
+(boolean)
+@param filePath file path of the text (string)
+@param rootPath root path to be used for SSI processing (str)
+@param useSphinx flag indicating to use Sphinx to generate the
+ReST preview (boolean)
+@param convertNewLineToBreak flag indicating to convert new lines
+to HTML break (Markdown only) (boolean)
+@param markdownHtmlFormat HTML format to be generated by markdown
+(string)
+@param restDocutilsHtmlFormat HTML format to be generated by docutils
+(string)
+@return processed HTML text (string)
+"""
+if language == "HTML":
+if ssiEnabled:
+html = self.__processSSI(text, filePath, rootPath)
+else:
+html = text
+return self.__processRootPath(html, rootPath)
+elif language == "Markdown":
+return self.__convertMarkdown(text, convertNewLineToBreak,
+markdownHtmlFormat)
+elif language == "ReST":
+return self.__convertReST(text, useSphinx, restDocutilsHtmlFormat)
+else:
+return self.tr(
+"<p>No preview available for this type of file.</p>")
+def __processSSI(self, txt, filename, root):
+"""
+Private method to process the given text for SSI statements.
+Note: Only a limited subset of SSI statements are supported.
+@param txt text to be processed (string)
+@param filename name of the file associated with the given text
+(string)
+@param root directory of the document root (string)
+@return processed HTML (string)
+"""
+if not filename:
+return txt
+# SSI include
+incRe = re.compile(
+r"""<!--#include[ \t]+(virtual|file)=[\"']([^\"']+)[\"']\s*-->""",
+re.IGNORECASE)
+baseDir = os.path.dirname(os.path.abspath(filename))
+docRoot = root if root != "" else baseDir
+while True:
+incMatch = incRe.search(txt)
+if incMatch is None:
+break
+if incMatch.group(1) == "virtual":
+incFile = Utilities.normjoinpath(docRoot, incMatch.group(2))
+elif incMatch.group(1) == "file":
+incFile = Utilities.normjoinpath(baseDir, incMatch.group(2))
+else:
+incFile = ""
+if os.path.exists(incFile):
+try:
+f = open(incFile, "r")
+incTxt = f.read()
+f.close()
+except (IOError, OSError):
+# remove SSI include
+incTxt = ""
+else:
+# remove SSI include
+incTxt = ""
+txt = txt[:incMatch.start(0)] + incTxt + txt[incMatch.end(0):]
+return txt
+def __processRootPath(self, txt, root):
+"""
+Private method to adjust absolute references to the given root path.
+@param txt text to be processed
+@type str
+@param root directory of the document root
+@type str
+@return processed HTML
+@rtype str
+"""
+if not root:
+return txt
+root = Utilities.fromNativeSeparators(root)
+if not root.endswith("/"):
+root += "/"
+rootLen = len(root)
+refRe = re.compile(
+r"""(href|src)=[\\"']/([^\\"']+)[\\"']""",
+re.IGNORECASE)
+pos = 0
+while True:
+refMatch = refRe.search(txt, pos)
+if refMatch is None:
+break
+txt = (txt[:refMatch.start(0)] + refMatch.group(1) + '="' + root +
+refMatch.group(2) + '"' + txt[refMatch.end(0):])
+pos = refMatch.end(0) + rootLen
+return txt
+def __convertReST(self, text, useSphinx, restDocutilsHtmlFormat):
+"""
+Private method to convert ReST text into HTML.
+@param text text to be processed (string)
+@param useSphinx flag indicating to use Sphinx to generate the
+ReST preview (boolean)
+@param restDocutilsHtmlFormat HTML format to be generated by docutils
+(string)
+@return processed HTML (string)
+"""
+if useSphinx:
+return self.__convertReSTSphinx(text)
+else:
+return self.__convertReSTDocutils(text, restDocutilsHtmlFormat)
+def __convertReSTSphinx(self, text):
+"""
+Private method to convert ReST text into HTML using 'sphinx'.
+@param text text to be processed (string)
+@return processed HTML (string)
+"""
+try:
+from sphinx.application import Sphinx   # __IGNORE_EXCEPTION__
+except ImportError:
+return self.tr(
+"""<p>ReStructuredText preview requires the"""
+""" <b>sphinx</b> package.<br/>Install it with"""
+""" your package manager,'pip install Sphinx' or see"""
+""" <a href="http://pypi.python.org/pypi/Sphinx">"""
+"""this page.</a></p>"""
+"""<p>Alternatively you may disable Sphinx usage"""
+""" on the Editor, Filehandling configuration page.</p>""")
+tempDir = tempfile.mkdtemp(prefix='eric-rest-')
+try:
+filename = 'sphinx_preview'
+basePath = os.path.join(tempDir, filename)
+fh = open(basePath + '.rst', 'w', encoding='utf-8')
+fh.write(text)
+fh.close()
+overrides = {'html_add_permalinks': False,
+'html_copy_source': False,
+'html_title': 'Sphinx preview',
+'html_use_index': False,
+'html_use_modindex': False,
+'html_use_smartypants': True,
+'master_doc': filename}
+app = Sphinx(srcdir=tempDir, confdir=None, outdir=tempDir,
+doctreedir=tempDir, buildername='html',
+confoverrides=overrides, status=None,
+warning=io.StringIO())
+app.build(force_all=True, filenames=None)
+fh = open(basePath + '.html', 'r', encoding='utf-8')
+html = fh.read()
+fh.close()
+finally:
+shutil.rmtree(tempDir)
+return html
+def __convertReSTDocutils(self, text, htmlFormat):
+"""
+Private method to convert ReST text into HTML using 'docutils'.
+@param text text to be processed (string)
+@param htmlFormat HTML format to be generated (string)
+@return processed HTML (string)
+"""
+if 'sphinx' in sys.modules:
+# Make sure any Sphinx polution of docutils has been removed.
+unloadKeys = [k for k in sys.modules.keys()
+if k.startswith(('docutils', 'sphinx'))]
+for key in unloadKeys:
+sys.modules.pop(key)
+try:
+import docutils.core    # __IGNORE_EXCEPTION__
+import docutils.utils   # __IGNORE_EXCEPTION__
+except ImportError:
+return self.tr(
+"""<p>ReStructuredText preview requires the"""
+""" <b>python-docutils</b> package.<br/>Install it with"""
+""" your package manager, 'pip install docutils' or see"""
+""" <a href="http://pypi.python.org/pypi/docutils">"""
+"""this page.</a></p>""")
+# redirect sys.stderr because we are not interested in it here
+origStderr = sys.stderr
+sys.stderr = io.StringIO()
+try:
+html = docutils.core.publish_string(
+text, writer_name=htmlFormat.lower()).decode("utf-8")
+except docutils.utils.SystemMessage as err:
+errStr = str(err).split(":")[-1].replace("\n", "<br/>")
+return self.tr(
+"""<p>Docutils returned an error:</p><p>{0}</p>"""
+).format(errStr)
+sys.stderr = origStderr
+return html
+def __convertMarkdown(self, text, convertNewLineToBreak, htmlFormat):
+"""
+Private method to convert Markdown text into HTML.
+@param text text to be processed (string)
+@param convertNewLineToBreak flag indicating to convert new lines
+to HTML break (Markdown only) (boolean)
+@param htmlFormat HTML format to be generated by markdown (string)
+@return processed HTML (string)
+"""
+try:
+import markdown     # __IGNORE_EXCEPTION__
+except ImportError:
+return self.tr(
+"""<p>Markdown preview requires the <b>Markdown</b> """
+"""package.<br/>Install it with your package manager,"""
+""" 'pip install Markdown' or see """
+"""<a href="http://pythonhosted.org/Markdown/install.html">"""
+"""installation instructions.</a></p>""")
+try:
+import mdx_mathjax  # __IGNORE_EXCEPTION__ __IGNORE_WARNING__
+except ImportError:
+# mathjax doesn't require import statement if installed
+# as extension
+pass
+if convertNewLineToBreak:
+extensions = ['fenced_code', 'nl2br', 'extra']
+else:
+extensions = ['fenced_code', 'extra']
+# version 2.0 supports only extension names, not instances
+if markdown.version_info[0] > 2 or \
+(markdown.version_info[0] == 2 and
+markdown.version_info[1] > 0):
+class _StrikeThroughExtension(markdown.Extension):
+"""
+Class is placed here, because it depends on imported markdown,
+and markdown import is lazy.
+(see https://pythonhosted.org/Markdown/extensions/api.html
+this page for details)
+"""
+DEL_RE = r'(~~)(.*?)~~'
+def extendMarkdown(self, md, md_globals):
+# Create the del pattern
+del_tag = markdown.inlinepatterns.SimpleTagPattern(
+self.DEL_RE, 'del')
+# Insert del pattern into markdown parser
+md.inlinePatterns.add('del', del_tag, '>not_strong')
+extensions.append(_StrikeThroughExtension())
+try:
+return markdown.markdown(text, extensions=extensions + ['mathjax'],
+output_format=htmlFormat.lower())
+except (ImportError, ValueError):
+# markdown raises ValueError or ImportError, depends on version
+# It is not clear, how to distinguish missing mathjax from other
+# errors. So keep going without mathjax.
+return markdown.markdown(text, extensions=extensions,
+output_format=htmlFormat.lower())

Mercurial Repositories > eric / file comparison

comparison: eric6/UI/Previewers/PreviewerHTML.py

eric6/UI/Previewers/PreviewerHTML.py