How to render PDF using pdf.js viewer in PyQt?

I have tried adding the pdf.js viewer files in my project and it works in browsers like Chrome, Mozilla, Safari, etc, but it's not loading some pages in node-webkit and PyQt webkit.

I am trying to load the file using an iframe, like this:

<iframe src="/test/?file=/assets/pdf/example.pdf#page=3"> </iframe>

I've found this thread over at the Qt Forums, where thebeast44 posted a snippet of Qt code answering your question. My translation to python is below.

You'll also need to unpack the res folder from the author's original code, I think he just modified the viewer... I've also attached said code here.

from PyQt4 import QtCore
from PyQt4 import QtGui
from PyQt4 import QtNetwork
from PyQt4 import QtWebKit


class PDFViewer(QtWebKit.QWebView):
    pdf_viewer_page = 'res/pdf-viewer.html'

    def __init__(self, parent=None):
        super().__init__(parent)
        self.settings = QtWebKit.QWebSettings.globalSettings()
        self.settings.setAttribute(QtWebKit.QWebSettings.LocalContentCanAccessFileUrls, True )
        self.settings.setAttribute(QtWebKit.QWebSettings.LocalContentCanAccessRemoteUrls, True )
        self.settings.setAttribute(QtWebKit.QWebSettings.DeveloperExtrasEnabled, True )
        nam = QtNetwork.QNetworkAccessManager()
        page = QtWebKit.QWebPage(self)
        page.setNetworkAccessManager(nam)
        self.setPage(page)
        self.loadFinished.connect(self.onLoadFinish)
        self.setUrl(QtCore.QUrl(self.pdf_viewer_page))

    def onLoadFinish(self, success):
        if success:
            self.page().mainFrame().evaluateJavaScript("init();")


if __name__ == '__main__':
    import sys
    app = QtGui.QApplication(sys.argv)
    viewer = PDFViewer(parent=None)
    viewer.show()
    sys.exit(app.exec_())

Below are some more up-to-date demo scripts for using pdf.js with PyQt4/QtWebKit or PyQt5/QtWebEngine. To try these, first download the latest stable version of pdf.js and unpack the zip file into a suitable location. (NB: if you're on Linux your distro may already have a pdf.js package, so that could be installed instead).

UPDATE:

As of Qt-5.13.0, it is also possible to use the built-in Chromium PDF Viewer with QWebEngineView:

import sys
from PyQt5 import QtCore, QtWidgets, QtWebEngineWidgets

PDF = 'file://path/to/my/sample.pdf'

class Window(QtWebEngineWidgets.QWebEngineView):
    def __init__(self):
        super(Window, self).__init__()
        self.settings().setAttribute(
            QtWebEngineWidgets.QWebEngineSettings.PluginsEnabled, True)
        self.settings().setAttribute(
            QtWebEngineWidgets.QWebEngineSettings.PdfViewerEnabled, True)
        self.load(QtCore.QUrl.fromUserInput(PDF))

if __name__ == '__main__':

    app = QtWidgets.QApplication(sys.argv)
    window = Window()
    window.setGeometry(600, 50, 800, 600)
    window.show()
    sys.exit(app.exec_())

PyQt5/QtWebEngine pdfjs script:

import sys
from PyQt5 import QtCore, QtWidgets, QtWebEngineWidgets

PDFJS = 'file:///path/to/pdfjs-1.9.426-dist/web/viewer.html'
# PDFJS = 'file:///usr/share/pdf.js/web/viewer.html'
PDF = 'file:///path/to/my/sample.pdf'

class Window(QtWebEngineWidgets.QWebEngineView):
    def __init__(self):
        super(Window, self).__init__()
        self.load(QtCore.QUrl.fromUserInput('%s?file=%s' % (PDFJS, PDF)))

if __name__ == '__main__':

    app = QtWidgets.QApplication(sys.argv)
    window = Window()
    window.setGeometry(600, 50, 800, 600)
    window.show()
    sys.exit(app.exec_())

PyQt4/QtWebKit pdfjs script:

import sys
from PyQt4 import QtCore, QtGui, QtWebKit

PDFJS = 'file:///path/to/pdfjs-1.9.426-dist/web/viewer.html'
# PDFJS = 'file:///usr/share/pdf.js/web/viewer.html'
PDF = 'file:///path/to/my/sample.pdf'

class Window(QtWebKit.QWebView):
    def __init__(self):
        super(Window, self).__init__()
        self.load(QtCore.QUrl.fromUserInput('%s?file=%s' % (PDFJS, PDF)))

if __name__ == '__main__':

    app = QtGui.QApplication(sys.argv)
    window = Window()
    window.setGeometry(600, 50, 800, 600)
    window.show()
    sys.exit(app.exec_())