Regression testing releases with Depicted (Dpxdt), Travis, & Saucelabs

Depicted is a release testing tool that compares before and after screenshots of your webpage, highlighting differences between the two.

Depicted supplements your release testing by allowing you to approve any visual changes a new release may cause.

I wrote a script during my time at Sprintly that would take a TravisCI build ID, pull related screenshots from our Saucelabs selenium tests, and upload them to a Depicted API server for comparison.

Before a new release would be deployed, we would manually run our Depicted release script and check and approve any changes.

This script was integrated as a Django management command for ease of use. Check out the full script below with comments.

Firefox & python Selenium: Stopping auto update on browser test runs

Found a minor annoyance when running headless selenium browser tests on Ubuntu server 16. For some reason automated tests would start failing when opening Firefox. Apparently the configuration i’m running allows for Firefox to run auto update when opened.

To stop Firefox auto updates during your python Selenium test run, load a custom profile:

from selenium import webdriver

profile = webdriver.FirefoxProfile()
profile.set_preference('app.update.auto', False)
profile.set_preference('app.update.enabled', False)

driver = webdriver.Firefox(profile)

If this doesn’t seem to do the trick, verify that apt unattended-upgrades are not causing this behavior. In one case, I saw that the update was happening in the /var/log/unattended-upgrades/unattended-upgrades-dpkg.log log file.

I disabled auto updates via apt globally with the command:

dpkg-reconfigure -plow unattended-upgrades

django-simple-redis-admin: Manage redis within the django admin

It’s been a while since I talked about anything i’ve been coding. A few months ago I released Django Simple Redis Admin, which allows you to manage redis cache keys within the Django admin. Something that annoys me with other django admin packages is the requirement to add database tables for their packages. django-simple-redis-admin gets around this by making a django model on the fly. No need for tables, just plug and play. Hopefully in the future i’ll be adding some filters and speeding things up. Check out django-simple-redis-admin on my GitHub page.

python-cloudcracker: a class to interface with the CloudCracker API

So I released a quick python class to interface with the CloudCracker API. CloudCracker is a new online password cracking service. Upload a pcap file, pay via BitCoin or Stripe, and they will crack the password for you. Pretty cool. Check out CloudCracker at cloudcracker.com and check out python-cloudcracker on GitHub.

Ultramemcache: python-ultramemcached and django-ultramemached-cache

A few months ago I came across a package on GitHub called Ultramemcache, which was described as “Ultra fast memcache client written in highly optimized C++ with Python bindings.”

Using Ulramemcache, I modified the common python-memcached library to use Ultramemcache, making sure it could be used as a drop in replacement. Check out python-ultramemcached on my GitHub page.

I also put together a django cache backend using Ultramemcache. This currently does not require my python-ultramemcached library. Check out django-ultramemcached-cache on my GitHub page.

Django runserver and gevent; NotImplementedError: gevent is only usable from a single thread

Hey. So I ran into a problem when using Django runserver and Requests for Python. Specifically, when running runserver, I came across the error:

NotImplementedError: gevent is only usable from a single thread

To fix this, you need to run the gevent monkey patch in your projects manage.py.

Add the following lines in the __main__ of your manage.py

from gevent import monkey
monkey.patch_all()

Your main will look as follows:

if __name__ == "__main__":
    import gevent
    from gevent import monkey
    monkey.patch_all()
    execute_manager(settings)