xvfbwrapper 0.2.10

Manage headless displays with Xvfb (X virtual framebuffer)

Manage headless displays with Xvfb (X virtual framebuffer)

---

Info:

• Development: https://github.com/cgoldberg/xvfbwrapper

• Releases: https://pypi.org/project/xvfbwrapper

• Author: Corey Goldberg - 2012-2025

• License: MIT

---

About xvfbwrapper:

xvfbwrapper is a python module for controlling virtual displays with Xvfb.

---

What is Xvfb?:

Xvfb (X virtual framebuffer) is a display server implementing the X11 display server protocol. It runs in memory and does not require a physical display or input devices. Only a network layer is necessary.

Xvfb is useful for running acceptance tests on headless servers.

---

Install xvfbwrapper from PyPI:

pip install xvfbwrapper

---

System Requirements:

• Python 3.8+

• X Window System

• Xvfb (sudo apt-get install xvfb, yum install xorg-x11-server-Xvfb, etc)

• File locking with fcntl

---

Examples:

Basic Usage:

from xvfbwrapper import Xvfb

vdisplay = Xvfb()
vdisplay.start()

try:
    # launch stuff inside virtual display here.
finally:
    # always either wrap your usage of Xvfb() with try / finally,
    # or alternatively use Xvfb as a context manager.
    # If you don't, you'll probably end up with a bunch of junk in /tmp
    vdisplay.stop()

---

Basic Usage, specifying display geometry:

from xvfbwrapper import Xvfb

vdisplay = Xvfb(width=1280, height=740)
vdisplay.start()

try:
    # launch stuff inside virtual display here.
finally:
    vdisplay.stop()

---

Basic Usage, specifying display number:

from xvfbwrapper import Xvfb

vdisplay = Xvfb(display=23)
vdisplay.start()
# Xvfb is started with display :23
# see vdisplay.new_display

---

Usage as a Context Manager:

from xvfbwrapper import Xvfb

with Xvfb() as xvfb:
    # launch stuff inside virtual display here.
    # Xvfb will stop when this block completes

---

Usage in Testing: Headless Selenium WebDriver Tests:

This test class uses selenium webdriver and xvfbwrapper to run tests on Chrome with a headless display.

import unittest

from selenium import webdriver
from xvfbwrapper import Xvfb


class TestPages(unittest.TestCase):

    def setUp(self):
        self.xvfb = Xvfb(width=1280, height=720)
        self.addCleanup(self.xvfb.stop)
        self.xvfb.start()
        self.browser = webdriver.Chrome()
        self.addCleanup(self.browser.quit)

    def testUbuntuHomepage(self):
        self.browser.get('https://www.ubuntu.com')
        self.assertIn('Ubuntu', self.browser.title)

    def testGoogleHomepage(self):
        self.browser.get('https://www.google.com')
        self.assertIn('Google', self.browser.title)


if __name__ == '__main__':
    unittest.main()

• virtual display is launched

• Chrome launches inside virtual display (headless)

• browser is not shown while tests are run

• conditions are asserted in each test case

• browser quits during cleanup

• virtual display stops during cleanup

Look Ma’, no browser!

(You can also take screenshots inside the virtual display to help diagnose test failures)

---

Usage with multi-threaded execution

To run several xvfb servers at the same time, you can use the environ keyword when starting the Xvfb instances. This provides isolation between threads. Be sure to use the environment dictionary you initialize Xvfb with in your subsequent system calls. Also, if you wish to inherit your current environment you must use the copy method of os.environ and not simply assign a new variable to os.environ:

from xvfbwrapper import Xvfb
import subprocess as sp
import os

isolated_environment = os.environ.copy()
xvfb = Xvfb(environ=isolated_environment)
xvfb.start()
sp.run(
    "xterm & sleep 1; kill %1 ",
    shell=True,
    env=isolated_environment,
)
xvfb.stop()

---

xvfbwrapper Development: running the unit tests:

To create a virtual env and install required testing libraries:

$ python -m venv venv
$ source ./venv/bin/activate
(venv)$ pip install -r requirements_test.txt

To run all tests, linting, and type checking across all supported/installed Python environments:

(venv)$ tox

To run all tests in the default Python environment:

(venv)$ pytest