Python + Selenium + PhantomJS render to PDF

22
votes

Is it possible to use PhantomJS's rendering to PDF capabilities when PhantomJS is being used in combination with Selenium and Python? (ie. mimic page.render('file.pdf') behaviour inside Python via Selenium).

I realize that this uses GhostDriver, and GhostDriver doesn't really support much in the way of printing.

If another alternative is possible that isn't Selenium, I'm all ears.

4
pythonseleniumphantomjs
Have you looked at Pypdf2? blog.pythonlibrary.org/tag/python-pdf-series - Amit Verma
@Amit: Rather extensively, as I use it all the time. Even Phaseit themselves have said that "PyPDF2 has no knowledge of HTML". It won't reliably render any HTML. - Rejected
@Rejected do you need the screenshot to occur at an exact state during testing? Or are you just looking to load a page & render to PDF? - Jacob Swartwood

4 Answers

11
votes

Here is a solution using selenium and special command for GhostDriver (it should work since GhostDriver 1.1.0 and PhantomJS 1.9.6, tested with PhantomJS 1.9.8):

#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""Download a webpage as a PDF."""


from selenium import webdriver


def download(driver, target_path):
    """Download the currently displayed page to target_path."""
    def execute(script, args):
        driver.execute('executePhantomScript',
                       {'script': script, 'args': args})

    # hack while the python interface lags
    driver.command_executor._commands['executePhantomScript'] = ('POST', '/session/$sessionId/phantom/execute')
    # set page format
    # inside the execution script, webpage is "this"
    page_format = 'this.paperSize = {format: "A4", orientation: "portrait" };'
    execute(page_format, [])

    # render current page
    render = '''this.render("{}")'''.format(target_path)
    execute(render, [])


if __name__ == '__main__':
    driver = webdriver.PhantomJS('phantomjs')
    driver.get('http://stackoverflow.com')
    download(driver, "save_me.pdf")

see also my answer to the same question here.

1
votes

You could use selenium.selenium.capture_screenshot('file.png') but that will give you a screen shot as a png not a pdf. There does not seem to be a way to get a screenshot as a pdf.

Here are the docs for capture_screenshot: http://selenium.googlecode.com/git/docs/api/py/selenium/selenium.selenium.html?highlight=screenshot#selenium.selenium.selenium.capture_screenshot

1
votes

Tried pdfkit? It can render PDF files from html pages.

0
votes

@rejected, I know you mentioned not wanting to use subprocesses, but...

You may actually be able to leverage subprocess communication more than you anticipated. Theoretically, you could take Ariya's stdin/stdout example and extend it to be a relatively generic wrapper script. It might first accept a page to load, then listen for (& execute) your test actions on that page. Eventually, you could kick off the .render or even make a generic capture for error handling:

try {
  // load page & execute stdin commands
} catch (e) {
  page.render(page + '-error-state.pdf');
}