Python

PyCon 2019 Reflections

When I was a kid, I was an enthusiastic Boy Scout. And every year, I looked forward to summer camp. For one full week, I would have a mini-adventure in the woods with my friends while earning new ranks and developing new skills. Summer camp was the highlight of every summer. As an adult, this is exactly how I feel about PyCon.

PyCon 2019 was my second time at PyCon. While I doubt any conference will ever have the same impact on me as my first PyCon, my second one was nevertheless every bit as good. I had a phenomenal experience. As always, I like to capture my reflections in an article so that I never forget the wonderful times I had. Here’s my story.

PrecisionLender

PyCon 2018 was a career-changing experience for me. I felt it at the time, and I can validate it now a year later. PyCon 2018 was my first serious engagement with the Python community. PyCon 2018 inspired me to speak at other conferences. PyCon 2018 introduced me to friends I still have today. As soon as PyCon 2018 ended, I knew that I needed to return for PyCon 2019.

Between 2018 and 2019, PrecisionLender (my employer) started doing much more Python work, especially in our data analytics division. I got approval from my manager to go to PyCon, but I also knew that others in the data division would benefit from PyCon as well. When I suggested the idea to the VP, he replied with one line: “Let’s do this thing!” With his blessing, I convinced four other PrecisionLender-ers to join me: Adam, Henry, Joe, and Raff.

I’m so thankful PrecisionLender approved our trips. Going with other friends from my company boosted not only my excitement for the conference but also my desire to learn new things. I’m proud to represent a company that supports its employees so well.

Art

Good conferences are good but exhausting. They cram
hundreds of adrenalized people into back-to-back activities requiring deep focus for hours at a time and for consecutive days. Amidst the mania, it is crucial to pace oneself. My friend Kojo sums this up perfectly in what he calls the “self care sprint.” It’s okay to step back to catch your breath. It’s vital to one’s mental health to take breaks, rest, and recover, especially at conferences as intense as PyCon.

Heeding Kojo’s advice, I took a #SelfCareSprint on the day before PyCon tutorials began. How so? I spent my afternoon at the Cleveland Museum of Art, which exhibits pieces from around the world dating from ancient times through the present day. Make no mistake: the Cleveland Museum of Art is world-class. In addition to their permanent collections, they had a special exhibit on Shinto artifacts from Japan. I barely had enough time to walk through all the galleries. What I did see impressed me, inspired me, and challenged me. Some pieces even spoke deeply to my soul.

The dichotomy of art and technology balance each other. Exploring pieces of art and the viewpoints they represent helped me center myself. I could clear my mind in preparation for the conference. I gained rest and recovery. I am human, after all.

Tutorials

PyCon 2019 hosted two days of tutorials before the main conference. Whereas talks are thirty minutes long and open to anyone, tutorials are three-hour sessions that require preregistration for limited seats. Tutorials are meant for hand-on learning with expert instructors. I had never attended tutorials at a conference before, and so this time, I wanted to try.

My first tutorial was Writing About Python (Even When You Hate Writing) by Thursday Bram. Since I do lots of blogging (and I ultimately want to write a book), I wanted to get first-hand advice on technical writing in the Python ecosystem. Thursday gave great advice on writing techniques and gotchas. The most valuable takeaway was her proofreading checklist. Her tutorial also inspired me to do something cool later in the conference. (Keep reading!)

My second tutorial was To trust or test? Automated testing of scientific projects with pytest. Unfortunately, this tutorial wasn’t right for me. I thought it would be about testing within data science, but it turned out to be a basic walkthrough of pytest. I didn’t learn any new material. What I did learn, though, was that I should be pickier with tutorials – I had to pay in advance, and I couldn’t just walk out to another talk.

My third tutorial was Escape from auto-manual testing with Hypothesis! by Zac Hatfield-Dodds. Hypothesis, a property-based testing tool, is hot right now. I first learned about it at the previous year’s PyCon, and I always wanted to learn more. Zac provided not only helpful lectures but a rigorous set of examples for us to complete. Hypothesis also works seamlessly with pytest. Zac made be a believer: Hypothesis is awesome! I need to spend more time learning it on my own.

Talks

As always, the talks were on point. I didn’t attend as many talks this year because I was too busy in the “hallway track,” but there were quite a few noteworthy ones that I attended.

In Don’t be a robot, build the bot, Mariatta showed how she and the Python core developers automated their GitHub workflow with the help of useful bots. It was cool to see how mundane processes can be automated away and how much more efficient teams can become.

In Break the Cycle: Three excellent Python tools to automate repetitive tasks, Thea Flowers showed how to use tox, nox, and Invoke to automate just about anything in Python. I’ll definitely refer back to this talk for testing.

In ¡Escuincla babosa!: Creating a telenovela script in three Python deep learning frameworks, Lorena Mesa showed us how serious machine learning can also be used for fun projects. Although the telenovela script she generated was short and humorous, it clearly proved that ML can get the job done.

In Scraping a Million Pokemon Battles: Distributed Systems By Example, Duy Nguyen showed how he scraped data from competitive Pokémon battles to level the playing field for new players. In the process, he developed a pretty slick distributed systems setup!

In Shipping your first Python package and automating future publishing, Chris Wilcox showed best practices on building and releasing Python packages. This talk was well-timed for me – I’ll definitely use this info for a current pet project of mine.

Dependency hell: a library author’s guide by Yanhui Li and Brian Quinlan will also be a great resource when considering dependencies for packages.

In to GIL or not to GIL: the Future of Multi-Core (C)Python, Eric Snow showed his thoughts for how to fix problems with the GIL and true multi-core processing.

In The Perils of Inheritance: Why We Should Prefer Composition, Ariel Ortiz made clear the nasty side effects inheritance can have and how composition is often a much better approach. The talk was fairly introductory, but I couldn’t agree more.

Expo

The expo hall was full of companies and organizations. The swankiest booths this year were:

  • Capital One – the Guido portrait and puzzle and the Zen of Python wall
  • Jetbrains – content developer tables for PyBites, Real Python, and others
  • Microsoft – four interactive Azure stations + active lab tables

However, my favorite company in the expo hall, hands down, was The Pokémon Company International. Their table was small and easily overlooked, but every time I passed by, it was packed. Everyone loves Pokémon! I got to meet a few of their engineers and managers. Apparently, they do much of their backend in Python. They’re also growing quite a lot. They were raffling off a giant Pikachu, and one of the engineers even developed a Google Home app that would make Pikachu respond whenever someone spoke to it! It was so charming to see them there. I’m glad that things are going well for Pokémon.

Swag

If you don’t overfill your swag bag, then you’re doing PyCon wrong. This year’s haul was as good as last year’s. I walked away with:

  • A dozen t-shirts
  • Half a dozen socks
  • An Adafruit kit from Microsoft
  • A signed copy of Flask Web Development from O’Reilly
  • A deck of cards with the Zen of Python from Capital One
  • An artistic deck of playing cards from Heroku
  • 16 packs of Pokémon cards
  • A JetBrains yo-yo
  • A few pairs of sunglasses
  • Water bottles from DoorDash, Wayfair, and Citadel
  • A guide to building Slack apps
  • Countless stickers

The best t-shirt award goes to Microsoft for their Visual Studio Code shirt, with honorable mentions for LinkedIn and SmartBear. I also shared a good amount of this swag with my coworkers at PrecisionLender.

Breweries

Cleveland (and greater Ohio) are renowned for craft breweries. Every time I return to Ohio, I’m always delighted by the beers I discover. I spent many lunches and dinners with a flight set on the side. Here’s where I went:

  • Hofbräuhaus Cleveland, twice! (I even bought the souvenir Maßkrug!)
  • Masthead Brewing Company
  • Noble Beast Brewing Company
  • Southern Tier Brewing Company
  • Great Lakes Brewing Company

The best was the Lichtenhainer from Noble Beast – a sour that tasted like a ham sandwich on sourdough. The worst was the “shampoo beer” from Southern Tier – did they forget to rinse the lines after cleaning them?

PyBites Dinner

Back at PyCon 2018, I met an Aussie by the name of Julian Sequeira, co-founder of PyBites. We hit it off. In fact, meeting Julian is one of the reasons why I continue to engage the Python community today. Through Julian, I met other friends like Jason Wattier, Brian Okken, Cristian Medina, and many others. Leading up to PyCon 2019, Julian organized a BIG dinner at Great Lakes Brewing Company for a bunch of Python content developers: PyBites, Real Python, Python Bytes, Test & Code, tryexceptpass, and Automation Panda (me!). Not only was it a time of sweet reunion, but I finally got to meet others like Bob Belderbos, Michael Kennedy, and David Amos in person. One of the best parts of the dinner was when a few of us chose to walk back to the hotels over the bridge instead of calling taxis. The night was cold, but the experience was worth every second.

Lightning Talk

Sadly, I did not get to deliver a full talk or tutorial at PyCon 2019. Believe me, I submitted. But that didn’t stop me from trying – there’s always one more chance with lightning talks! One exercise during the Writing About Python tutorial was to pitch a lightning talk idea. At the time, I struggled to come up with a good topic. I first considered something about testing or being a tester, but those ideas just didn’t feel right. Then, I struck gold: what about giving helpful tips for blogging, based on my experiences with Automation Panda?

I put my idea on the call-for-lightning-talk-proposals on Saturday morning: “3 Quick Tips for Software Blogging.” When I didn’t receive any notification by lunchtime, I thought my pitch had been rejected. Then, while chilling in the quiet room at 3pm, I received an email: “Congrats! You’re giving your lightning talk today at 5pm!” Excitement, then panic, took over. I threw some slides together, rehearsed them in my head, and marched myself to the main auditorium. My lightning talk was second in queue, and I delivered it like a BOSS!

PyCarolinas

Ever since my first PyCon, I’ve dreamed about having a Python conference in the Carolinas. There was a PyCarolinas 2012 and a PyData Carolinas 2016, but both were one-hit wonders. My dream remained in my back pocket until PyCon 2019.

While meandering the expo hall on Friday, I ran into Tim Hopper and Brian Corbin, two friends who were also from the Carolinas. We talked about lots of things, but one point of discussion was about relaunching PyCarolinas. Later, Dustin Ingram, chair of PyTexas, tweeted that there would be a conference organizer’s open space on Saturday. I asked if I could join because of my PyCarolinas dreams, and he said absolutely yes. Brian and I both attended, made connections, and got tons of helpful information.

Dustin then asked me if I’d like to include a slide for PyCarolinas in the “regional conference parade” on Sunday morning after the lightning talks. Heck yeah! PyCarolinas was the very last slide as a call-to-action: We have a dream; come help us make it real!

At 10am on Sunday, I held an open space to talk about (re)launching PyCarolinas. 26 people came! We got everyone’s info, created a Slack room, and started throwing around ideas. In the week after the conference, over a hundred people signed up for our Slack room. The excitement is palpable. Our goal is to host PyCarolinas in summer of 2020 for 150+ people. I’m so thankful I got the opportunity to be the spark that lit this wildfire, on such a big stage.

Twitter

Together with my blog, I use my Twitter handle @AutomationPanda for professional development. Twitter is especially helpful during conferences for communicating with friends and sharing experiences. During PyCon 2019, I crossed a big milestone: I hit over 1000 followers! That was cool.

I also made my first viral tweet, thanks to a sticker from Facebook:

Friends

If you read these reflections down this far, thank you. Seriously, I mean it.

The best part about PyCon 2019 for me was the time I spent with my friends.

The previous year at PyCon 2018, I went in blind. I did not know anyone. Along the way, I met Julian, Dustin, Gabriel Boorse, and Jon Banafato. At PyOhio 2018, I met Adrienne Lowe, Trey Hunner, and Jason Wattier. From there, I just kept meeting and re-meeting great people: PyGotham 2018, PyCon Canada 2018, PyCaribbean 2019, and PyTexas 2019.

PyCon 2019 was a high point for friendships. Everyone I knew was there. I couldn’t walk for 10 minutes around the convention center without running into someone I knew. I feel like I’m truly part of the Python community now. Here were just a few highlights:

  • Going there with my PL team: Adam, Henry, Joe, and Raff.
  • German dinner and souvenir Maßkrugs with Adam at Hofbräuhaus.
  • “Shampoo” beer with Joe and Adam at Southern Tier.
  • Snagging Pokémon cards on opening night with Mason Egger, and then running into Jason Wattier on the way.
  • Ramen dinner and Hilton rooftop drinks with the PL crew plus Mason.
  • Impromptu lunch with Adrienne so she could share the awesome things she’s accomplishing.
  • The Great Lakes dinner with Julian and company.
  • Hallway track encounters with Daniel Furman, Veronica Hanus, Trey Hunner, Piper Thunstrom, Mark Locatelli, Brian Corbin, Tim Hopper, and many others.
  • A true Saturday night Hofbräuhaus party with the PL crew, Mark, Mason, Gabriel, William Horton, and the funniest waitress ever.
  • The Great Lakes dinner with Mason, Gabriel, William, Aly Sivji, and Etienne.
  • #PyMansion that needs to happen.

PyCon 2019 filled my head with knowledge and my heart with love. I even took a new Pythonic nickname: “Pandy.” I can’t wait for more conferences like this!

PyCon Canada 2018 Reflections

PyCon Canada 2018 was my fourth and final Python conference of 2018. I proposed a talk on a whim after seeing the CFP on Twitter. What the heck, why not? It couldn’t hurt to try. Much to my surprise (and delight), I was accepted to speak! So, up to the Great White North I went for the first time since childhood.

The Conference

#PyConCA2018 took place in Toronto, Ontario from November 10-13 at the Chestnut Residence downtown. I attended the conference (Nov 10-11) but skipped out on the sprints (Nov 12-13). It looked like about 400-500 people attended the conference, but I don’t know the exact count. A few vendors had tables with swag, but the talks were clearly the main focus of the conference.

A great view of downtown Toronto from my Chinatown Airbnb

The Talks

PyConCA offered three tracks for talks plus a tutorials track. There were two time slot lengths for talks: 10 minutes and 30 minutes. I had not attended a conference with short 10-minute talks before, but they turned out to be a great way to cover a broader range of topics in a short amount of time. The tutorials were long-running sessions for which anyone could register at no additional charge, but they each had a limited number of seats. (I regret not signing up in advance for the Kubernetes tutorial.) There were also four decent keynote addresses.

I attended the following talks:

  1. A Bossy Sort of Voice: Uncovering gender bias in Harry Potter with Python
  2. Replacing Guido
  3. Guide to your own artificial intelligence application in 3 easy steps
  4. Who’s There? Building a home security system with Pi & Slack!
  5. PEP 572: The Walrus Operator
  6. WSGI for Web Developers
  7. Get Productive with Python in Visual Studio Code
  8. Lessons learned open sourcing (and maintaining) my first library
  9. Nimble Testing!

My Talk

My talk was entitled, “Behavior-Driven Python with pytest-bdd”. It was a recasting of my PyCon 2018 talk on Python’s behave framework using pytest-bdd instead.

Prepping for my talk at my Airbnb with my toque and Royaltea glass!

I spent a lot of time reworking the slides, writing new example code, and rehearsing my words before the talk. And I felt great when I presented it: without any script, I hit all the major points without skipping a beat and ended right on time. I felt my passion flow through me as I spoke. This tweet pretty much summed up my feelings:

The People

Meeting people is one of my favorite parts of Python conferences. Everyone is friendly. Everyone will chat with you. Everyone will get excited about whatever makes you excited. This time around, I ended up in a posse with a few other guys who mostly attended the same talks and also sat at the same lunch table. I hope our paths cross again. I also got to meet Elaine Wong, the conference chair.

After the Conference

I was on my own for both evenings after the conference talks. My Airbnb rental was just two blocks away in Chinatown, so I could walk to and from the conference center (in the bitter Toronto cold). On Saturday night, I ate a delicious dry hotpot of beef, lotus flowers, and wood ear mushrooms at the House of Gourmet, followed by a fancy bubble tea in a light-bulb-shaped glass across the street at Royaltea. On Sunday night, I treated myself to foot-and-body massage at Evergreen Beauty and Wellness. My therapist, who was from Beijing, helped me practice my Mandarin. Thereafter, I went to Sichuanren for an all-you-can-eat hotpot buffet: beef, pork, lamb, seafood, and veggies. It’s so much fun to visit a big city with a large Chinatown – it provides access to things I can’t always get at home. That US-to-Canadian-dollar exchange rate is quite favorable, too. The only challenges I faced were (a) no mobile phone service and (b) worrying if establishments would accept my credit/debit cards. The temps also hovered around freezing.

Takeaways

PyConCA was a strong finish for my 2018 conferences. I’m so thankful for my opportunity to speak, and I’m glad that I took the time to attend.

My favorite physical takeaway items of swag were:

  • My PyConCA sticker, now proudly displayed on my Macbook
  • My PyConCA t-shirt, which will soon appear in my rotation
  • My PyConCA “toque” (Canadian word for “knit winter cap with a pom-pom on top”)
One more badge, and one more sticker!

My main inspirational takeaway from this conference could be summed up in one word: confidence. I feel much more confident in myself as a conference speaker after nailing my talk this fourth time. After listening to a number of talks, I also feel much more confident in my Python web development skills. Picking up Flask (which is on my todo list) should be doable. Finally, I feel capable of learning data science and AI with Python when the time comes. Many talks showed how machine learning can solve novel problems with straightforward tools and techniques.

That should conclude this panda’s round of conferences for the year. I look forward to what 2019 brings!

PyTexas 2019 Reflections

PyTexas 2019 was an incredible Python conference. It was held at the Central Library in Austin, Texas from April 13-14. I’m so glad I went. Even though this was my seventh Python conference, it was one of my favorites so far. Here’s a brief recap of my experiences.

Why I Went

I consider myself very fortunate to have been able to go to PyTexas 2019. After my talk proposals for PyCon 2019 were rejected, I saw this tweet from Dustin Ingram, the conference chair for PyTexas:

Reinvigorated, I decided to give it a try. Lo and behold, one of my talks, Egad! How Do We Start Writing (Better) Tests?, was accepted! The video recording is below:


Thankfully, my talk was the very second talk of the conference. I could get it out of the way early so I could enjoy the rest of the conference without the nerves. And everyone always loves the pandas.

I also gave a Lightning Talk for the first time! I talked about the difference between unittest and pytest. My talk starts at 30:17, but be sure to listen to all of the talks.

I’d also like to thank my employer, PrecisionLender, for sponsoring my trip and enabling me to speak.

Memorable Moments

Talks are usually the main part of any conference. PyTexas 2019 was a single-track conference, meaning that everyone saw all of the talks. All talks were memorable for me, but I’ll write a separate post about the talks once all the recordings are posted. Here, I’ll cover other awesome things that happened.

My Recovery Day

Things had been very stressful for me in the first few months of 2019. I came to PyTexas essentially exhausted from life, and I needed a “Self Care Sprint” (as Kojo would say). So, that’s exactly what I did: I flew into Austin on Friday morning and spent the whole afternoon just being a low-key tourist. I ate a Texas-sized lunch at Stubb’s BBQ, viewed the artwork at Mexic-Arte Museum, walked along the Colorado River, and nearly fell asleep in the Central Library after perusing the stacks. That evening, I met up with other speakers at the Spider House for an informal pre-conference get-together. Even though I wasn’t “productive” by any professional definition, I felt thoroughly refreshed and ready for the excitement to come.

Electric Scooters

Austin has been invaded by electric scooters. They are on every street corner. There must be half a dozen different brands. Even Uber and Lyft have scooters for rent! Instead of hailing ride shares downtown, I just hopped the nearest Lime scooter. They go really fast, and they’re tons of fun!

The First After-Party

Literati Books generously hosted an after-party at Jo’s Coffee after the first day of the conference. I got to spend time with a bunch of cool people from the conference while enjoying sliders and craft beer. Carl even shared some of his jerky with us!

Other Testing Talks

I always get a rise out of testing talks at conferences. Python conferences always have a few but only a few. PyTexas had three. I think Kojo‘s tweets summed up my enthusiasm perfectly:

The Zen of Python Teams

Adrienne delivered one of the best keynote addresses I’ve ever attended. Seriously, go watch it. She talked about how the Zen of Python can be applied not only to code but also to teams. The best part was the “Easter egg” at the end. The Zen of Python famously leaves the 20th line blank so that we can make it for ourselves. Adrienne challenged us to come up with our own 20th point after handing out real Easter eggs to everyone in the audience! Mine? People matter.

Whataburger

I had never eaten at Whataburger before. This trip, that changed. William, Brian, and I hopped on those electric scooters and went to the Whataburger across the river for lunch on day 2. The patty melt was tasty, but the Dr. Pepper milkshake was out of this world! The views from the bridge were gorgeous as well.

The Second After-Party

After the conference ended, William, Aly, and I went to Mort Subite, a cool Belgian beer bar, to celebrate and unwind. Then, we rode electric scooters over to Baton Creole for a late-night dinner with Adrienne. We had some good food and even better discussions. It was the best way to end PyTexas!

Takeaways

PyTexas was the first conference where I felt like I fully belonged from day one. Every previous conference was a bit of a shot in the dark for me because I was still new to the Python community. PyTexas 2019 felt almost like a reunion. I strengthened existing friendships and made new ones: Adrienne, Kojo, Dustin, Ernest, Aly, William, Piper, Andy, Carl, Mason, Michael, Brian, and so many more. I also felt like I made a bigger impact at PyTexas than at other conferences because I genuinely felt like part of the community.

We should never take conferences (or any moments) for granted. Truly wonderful things happened at PyTexas. I felt creative. I felt inspired. I felt challenged by new ideas. I felt the itch to try new things. I left on a post-conference high and, surprisingly, I wasn’t particularly tired. The organizers did a phenomenal job running the conference smoothly and successfully. Seriously, hats off to them – many thanks for a job well done. As attendees, we should be grateful for all the hard work so many people did for the conference, and we should capitalize on what we take away from the conference.

Single-track and multi-track yield two very different conference experiences. PyTexas 2019 was my second single-track conference and my first one for a Python conference. Overall, I think the single-track format worked very well. Putting everyone on the same track in the same room builds a strong sense of camaraderie. It also gives speakers a much more prominent platform. However, multi-track provides more choices for attendees, and it gives more people the opportunity to speak. Both are good. I think it would be cool if future conferences do both: maybe one day for single-track and another day for multi-track.

I’m going to (attempt to) develop a new Python package. For a while, I’ve wanted to implement a particular testing pattern in a Pythonic way. My goal is to develop and release it to PyPI as an open-source package. I never had the time or clarity to do it until now. PyTexas gave me a huge boost, and I hope I can carry my vision through to delivery!

People matter. The Python community is a truly wonderful group. People come for the language and stay for the community – it’s true. PyTexas 2019 has challenged me to be a better person and to help people through software.

One final takeaway – another conference sticker!

Python BDD Framework Comparison

Almost every major programming language has BDD test frameworks, and Python is no exception. In fact, Python has several! So, how do they compare, and which one is best? Let’s find out.

Head-to-Head Comparison

behave

behave is one of the most popular Python BDD frameworks. Although it is not officially part of the Cucumber project, it functions very similarly to Cucumber frameworks.

Pros

  • It fully supports the Gherkin language.
  • Environmental functions and fixtures make setup and cleanup easy.
  • It has Django and Flask integrations.
  • It is popular with Python BDD practitioners.
  • Online docs and tutorials are great.
  • It has PyCharm Professional Edition support.

Cons

  • There’s no support for parallel execution.
  • It’s a standalone framework.
  • Sharing steps between feature files can be a bit of a hassle.

pytest-bdd

pytest-bdd is a plugin for pytest that lets users write tests as Gherkin feature files rather than test functions. Because it integrates with pytest, it can work with any other pytest plugins, such as pytest-html for pretty reports and pytest-xdist for parallel testing. It also uses pytest fixtures for dependency injection.

Pros

  • It is fully compatible with pytest and major pytest plugins.
  • It benefits from pytest‘s community, growth, and goodness.
  • Fixtures are a great way to manage context between steps.
  • Tests can be filtered and executed together with other pytest tests.
  • Step definitions and hooks are easily shared using conftest.py.
  • Tabular data can be handled better for data-driven testing.
  • Online docs and tutorials are great.
  • It has PyCharm Professional Edition support.

Cons

  • Step definition modules must have explicit declarations for feature files (via “@scenario” or the “scenarios” function).
  • Scenario outline steps must be parsed differently.

radish

radish is a BDD framework with a twist: it adds new syntax to the Gherkin language. Language features like scenario loops, scenario preconditions, and constants make radish‘s Gherkin variant more programmatic for test cases.

Resources

Logo

Pros

  • Gherkin language extensions empower testers to write better tests.
  • The website, docs, and logo are on point.
  • Feature files and step definitions come out very clean.

Cons

  • It’s a standalone framework with limited extensions.
  • BDD purists may not like the additions to the Gherkin syntax.

lettuce

lettuce is another vegetable-themed Python BDD framework that’s been around for years. However, the website and the code haven’t been updated for a while.

Resources

Logo

../_images/flow.png

Pros

  • Its code is simpler.
  • It’s tried and true.

Cons

  • It lacks the feature richness of the other frameworks.
  • It doesn’t appear to have much active, ongoing support.

freshen

freshen was one of the first BDD test frameworks for Python. It was a plugin for nose. However, both freshen and nose are no longer maintained, and their doc pages explicitly tell readers to use other frameworks.

My Recommendations

None of these frameworks are perfect, but some have clear advantages. Overall, my top recommendation is pytest-bdd because it benefits from the strengths of pytest. I believe pytest is one of the best test frameworks in any language because of its conciseness, fixtures, assertions, and plugins. The 2018 Python Developers Survey showed that pytest is, by far, the most popular Python test framework, too. Even though pytest-bdd doesn’t feel as polished as behave, I think some TLC from the open source community could fix that.

Here are other recommendations:

  • Use behave if you want a robust, clean experience with the largest community.
  • Use pytest-bdd if you need to integrate with other plugins, already have a bunch of pytest tests, or want to run tests in parallel.
  • Use radish if you want more programmatic control of testing at the Gherkin layer.
  • Don’t use lettuce or freshen.

PyCaribbean 2019 Reflections

PyCaribbean was held in Santo Domingo, Dominican Republic from February 16-17, 2019. I was blessed with the opportunity to deliver not just one talk but two at the conference! Typically, I write lengthy chronological reflections of my conference experiences, but this time, I’m going to share my big takeaways.

The welcome banner. This conference was #lit!

Python has GREAT people.

Python is truly just as much about the community as it is about the language, and conferences are one of the best ways to become part of that community. Everyone at PyCaribbean was excited to learn, grow, and be inspired. Here’s a short list of Twitter handles for some of the awesome folks who made a direct impact on me at the conference:

There were many others, too. I felt like I really got to connect with these folks, not just meet them in passing.

This was the room for my talk. Everyone was eager to learn about testing!

The Dominican Republic has GREAT people.

First of all, many thanks to Leonardo Jimenez for organizing the conference! He did so much not only to bring together an excellent program of speakers and events, but he also got the support of the local software community and even the government in the DR.

PyCaribbean really showed the best of the software world in the DR. Everyone there was hungry to learn and share. I had no idea how vibrant the software industry was becoming there, too. There’s a bright future ahead.

Don’t wait to make proposals to conferences.

I consider myself especially fortunate to have attended PyCaribbean because I almost didn’t get to go. I submitted my talk proposals one night on a whim after seeing the PyCaribbean Twitter handle appear on my feed. After submitting two talks, my third one got blocked with a message saying submissions had been closed. Had I delayed a few minutes, I would have been too late!

Join the PSF.

The Python Software Foundation (PSF) is a 501(c)(3) non-profit corporation that holds the intellectual property rights behind the Python programming language.

https://www.python.org/psf/

The PSF does awesome things for the community, such as running PyCon. Anyone can become a member, too! There are different membership classes for varying levels of involvement. Lorena Mesa, one of the PSF Directors, encouraged me to join during the conference. If you care about Python, then I encourage you to join as well!

Beach trips are fun.

The day after the conference ended, a bunch of us (mostly speakers) took a day trip to Be Live Collection Canoa at Bayahibe. This was my first time at an all-inclusive beach resort. The water was a clear light blue, and the sand was white. Mixed drinks and Presidente beers were unlimited – you could even order them from a bar in the swimming pool! The buffet lunch was also on point. Plus, the trip offered the perfect chance to get to know the others on a deeper level. I almost didn’t get to go, but thankfully Delta rearranged my flights due to weather delays and gave me an extra day in the DR. I needed that day at the beach to just be me, but relaxed. #WorthIt

Music brings people together.

One of the conference highlights was the electric violin performance on day 2. I don’t know the name of the musician, but he shredded it! He played “Wake Me Up” by Avicii, “Uptown Funk” by Bruno Mars, and “Corazon Espinado” by Santana. As I sat in the auditorium listening with the others, I just thought to myself, “This is really nice. This is a once-in-a-life performance for incredible renditions of these three awesome songs.” Everyone else there seemed to agree with me.

“Wake Me Up” (Avicii)
“Corazon Espinado” (Santana)

Passionfruit is delicious.

I ate passionfruit for the first time in my life in the DR. It was delicious. The edible flesh of the fruit is basically a gooey collection of black seeds in a yellow mucus. It tastes tart but slightly sweet. I normally don’t eat breakfast, but I devoured about four halves on the morning I first discovered them. They had them at the beach resort buffet, too!

Where has passionfruit been all my life?

I need to stick up for myself.

During my trip, it was very obvious that I was a tourist – a white American who spoke no Spanish and wandered around just to look at things. Unfortunately, because of that, some people tried to take advantage of me. I was clearly overcharged for my souvenirs, even after attempting to haggle. A guard at Independence Park took my phone to take pictures of me and then demanded money. On my return flight, a guy sat in my seat on the plane and refused to yield it to me.

These experiences really frustrated me. I’ve always been somewhat shy in social circumstances, and that leaves me vulnerable to others who would take advantage of me. Reflecting on how I handled these situations has made me determined to be more assertive. I won’t become a jerk, but I don’t need to be afraid to stick up for myself. I should use my inner strength and discernment instead of folding.

The world is a fallen place.

One thing truly broke my heart during my trip: I’m 99% sure I witnessed prostitution on multiple occasions. I won’t go into details, but it was shocking to me. Call me naïve. Let’s work to make a better world where this sort of thing doesn’t need to happen.

I know so little.

My PyCaribbean trip was challenging but rewarding. It was my first time visiting the Caribbean and Latin America. Not only did I gain some software experience, but I also gained some life experience. I’m thankful I got to go and that all the details fell perfectly into place. Hopefully, I’ll get to return to learn even more!

Time lapse while riding the JFK AirTrain

Python Testing 101: pytest-bdd

Warning: If you are new to BDD, then I strongly recommend reading the BDD 101 series before trying to use pytest-bdd. Also, make sure that you are already familiar with the pytest framework.

Overview

pytest-bdd is a behavior-driven (BDD) test framework that is very similar to behaveCucumber and SpecFlow. BDD frameworks are very different from more traditional frameworks like unittest and pytest. Test scenarios are written in Gherkin “.feature” files using plain language. Each Given, When, and Then step is “glued” to a step definition – a Python function decorated by a matching string in a step definition module. This means that there is a separation of concerns between test cases and test code. Gherkin steps may also be reused by multiple scenarios.

pytest-bdd is very similar to other Python BDD frameworks like behave, radish, and lettuce. However, unlike the others, pytest-bdd is not a standalone framework: it is a plugin for pytest. Thus, all of pytest‘s features and plugins can be used with pytest-bdd. This is a huge advantage!

Installation

Use pip to install both pytest and pytest-bdd.

pip install pytest
pip install pytest-bdd

Project Structure

Project structure for pytest-bdd is actually pretty flexible (since it is based on pytest), but the following conventions are recommended:

  • All test code should appear under a test directory named “tests”.
  • Feature files should be placed in a test subdirectory named “features”.
  • Step definition modules should be placed in a test subdirectory named “step_defs”.
  • conftest.py files should be located together with step definition modules.

Other names and hierarchies may be used. For example, large test suites can have feature-specific directories of features and step defs. pytest should be able to discover tests anywhere under the test directory.

[project root directory]
|‐‐ [product code packages]
|-- [test directories]
|   |-- features
|   |   `-- *.feature
|   `-- step_defs
|       |-- conftest.py
|       `-- test_*.py
`-- [pytest.ini|tox.ini|setup.cfg]

Note: Step definition module names do not need to be the same as feature file names. Any step definition can be used by any feature file within the same project.

Example Code

An example project named behavior-driven-python located in GitHub shows how to write tests using pytest-bdd. This section will explain how the Web tests are designed.

The top layer for pytest-bdd tests is the set of Gherkin feature files. Notice how the scenario below is concise, focused, meaningful, and declarative:

@web @duckduckgo
Feature: DuckDuckGo Web Browsing
  As a web surfer,
  I want to find information online,
  So I can learn new things and get tasks done.

  # The "@" annotations are tags
  # One feature can have multiple scenarios
  # The lines immediately after the feature title are just comments

  Scenario: Basic DuckDuckGo Search
    Given the DuckDuckGo home page is displayed
    When the user searches for "panda"
    Then results are shown for "panda"

Each scenario step is “glued” to a decorated Python function called a step definition. Step definitions are written in Python test modules, as shown below:

import pytest

from pytest_bdd import scenarios, given, when, then, parsers
from selenium import webdriver
from selenium.webdriver.common.keys import Keys

# Constants

DUCKDUCKGO_HOME = 'https://duckduckgo.com/'

# Scenarios

scenarios('../features/web.feature')

# Fixtures

@pytest.fixture
def browser():
    b = webdriver.Firefox()
    b.implicitly_wait(10)
    yield b
    b.quit()

# Given Steps

@given('the DuckDuckGo home page is displayed')
def ddg_home(browser):
    browser.get(DUCKDUCKGO_HOME)

# When Steps

@when(parsers.parse('the user searches for "{phrase}"'))
def search_phrase(browser, phrase):
    search_input = browser.find_element_by_id('search_form_input_homepage')
    search_input.send_keys(phrase + Keys.RETURN)

# Then Steps

@then(parsers.parse('results are shown for "{phrase}"'))
def search_results(browser, phrase):
    # Check search result list
    # (A more comprehensive test would check results for matching phrases)
    # (Check the list before the search phrase for correct implicit waiting)
    links_div = browser.find_element_by_id('links')
    assert len(links_div.find_elements_by_xpath('//div')) > 0
    # Check search phrase
    search_input = browser.find_element_by_id('search_form_input')
    assert search_input.get_attribute('value') == phrase

Notice how each Given/When/Then step has a function with an appropriate decorator. Arguments, such as the search “phrase,” may also be passed from step to function. pytest-bdd provides a few argument parsers out of the box and also lets programmers implement their own. (By default, strings are compared using equality.) One function can be decorated for many steps, too.

pytest fixtures may also be used by step functions. The code above uses a fixture to initialize the Firefox WebDriver before each scenario and then quit it after each scenario. Fixtures follow all the same rules, including scope. Any step function can use a fixture by declaring it as an argument. Furthermore, any “@given” step function that returns a value can also be used as a fixture. Please read the official docs for more info about fixtures with pytest-bdd.

One important, easily-overlooked detail is that scenarios must be explicitly declared in test modules. Unlike other BDD frameworks that treat feature files as the main scripts, pytest-bdd treats the “test_*.py” module as the main scripts (because that’s what pytest does). Scenarios may be specified explicitly using scenario decorators, or all scenarios in a list of feature files may be included implicitly using the “scenarios” shortcut function shown above.

To share steps across multiple feature files, add them to the “conftest.py” file instead of the test modules. Since scenarios must be declared within a test module, they can only use step functions available within the same module or in “conftest.py”. As a best practice, put commonly shared steps in “conftest.py” and feature-specific steps in the test module. The same recommendation also applies for hooks.

Scenario outlines require special implementation on the Python side to run successfully. Unfortunately, steps used by scenario outlines need unique step decorators and extra converting. Please read the official docs or the example project to see examples.

Test Launch

pytest-bdd can leverage the full power of pytest. Tests can be run in full or filtered by tag. Below are example commands using the example project:

# run all tests
pytest

# filter tests by test module
# note: feature files cannot be run directly
pytest tests/step_defs/test_unit_basic.py
pytest tests/step_defs/test_unit_outlines.py
pytest tests/step_defs/test_unit_service.py
pytest tests/step_defs/test_unit_web.py

# filter tests by tags
# running by tag is typically better than running by path
pytest -k "unit"
pytest -k "service"
pytest -k "web"
pytest -k "add or remove"
pytest -k "unit and not outline"

# print JUnit report
pytest -junitxml=/path/for/output

pytest-bdd tests can be executed and filtered together with regular pytest tests. Tests can all be located within the same directory. Tags work just like pytest.mark. As a warning, marks must be explicitly added to “pytest.ini” starting with pytest 5.0.

All other pytest plugins should work, too. For example:

Pros and Cons

Just like for other BDD frameworks, pytest-bdd is best suited for black-box testing because it forces the developer to write test cases in plain, descriptive language. In my opinion, it is arguably the best BDD framework currently available for Python because it rests on the strength and extendability of pytest. It also has PyCharm support (in the Professional Edition). However, it can be more cumbersome to use than behave due to the extra code needed for declaring scenarios, implementing scenario outlines, and sharing steps. Nevertheless, I would still recommend pytest-bdd over behave for most users because it is more powerful – pytest is just awesome!

Speaking Pythonese

The Python community, like many groups, has its own language – and I don’t mean just Python. There are many words and phrases thrown around that may confuse people new to Python. I originally shared some terms in my article, Which Version of Python Should I Use?, but below are some more of those colloquialisms for quick reference:

Word or Phrase Meaning
Anaconda
  • Open-source implementation of Python (and R)
  • Meant for data scientists
  • Uses the conda package manager
Benevolent Dictator for Life (BDFL)
  • Guido van Rossum
  • The inventor of Python
  • Resigned in July 2018 but remains BDFL Emeritus
The CheeseShop
  • a fun code name for the Python Package Index
Class
  • A programming definition for creating objects
  • Combines attributes (variables) and behaviors (methods)
  • Useful for reusing code
Conda
  • Package manager for Python and other languages
  • Part of the Anaconda project
Core Developer
  • A developer who has commit privilege to the CPython codebase
  • Very few Pythonistas are core developers
CPython
  • The default and most widely used implementation of the Python language
  • Implemented in C
Django
  • A batteries-included Python Web framework for perfectionists with deadlines
  • Offers many features out of the box
  • The most popular Python framework in 2017
  • Size: Flask < Pyramid < Django
Flask
  • A microframework for Python Web development
  • Uses Werkzeug and Jinja2
  • Super-minimalist
  • Size: Flask < Pyramid < Django
Function
  • A definition for a callable subroutine
  • May take inputs
  • May return outputs
  • Great for code reuse
  • Functions are first-order values
The Hitchhiker’s Guide to Python
  • A popular online guide to Python
  • Opinionated
  • Shares many good best practices
Jinja2
  • A Python template engine
  • Inspired by Django’s templates
Jupyter
  • A project for interactive Python development
  • “Jupyter Notebooks” allow programmers to dynamically rewrite and rerun Python code, and then share code easily with others
  • Popular with data scientists
Module
  • A Python source code file containing definitions and statements
  • Every .py file is a module
  • May be imported by other modules to reuse code
NumPy
  • A popular Python package for scientific computing
Pandas
  • A popular Python package for data analysis
pip
  • The PyPA-recommended tool for installing Python packages
  • Command: “pip install “
  • Recursive acronym for “pip installs packages”
PyBites
  • A community of Pythoneers who improve their skills through code challenges
PyCharm
  • A popular Python IDE developed by JetBrains
  • Offers great development features
  • Has a free Community Edition and a paid Professional Edition
PyCon
  • The annual Python conference held in North America
  • GO – it will change your life!
  • Several other conferences are held worldwide
PyPy
  • An alternative Python implementation
  • Known for speed, memory usage, and compatibility
  • Good alternative to CPython for high performance workloads
Pyramid
  • A Python Web framework
  • Start small, finish big, stay finished
  • Provides many parts but not everything (such as ORM)
  • Size: Flask < Pyramid < Django
pytest
  • A lightweight-yet-powerful Python test framework (and arguably the best)
Python 2
  • The old version of Python
  • Will reach end-of-life in 2020
  • Final version will be 2.7.x
  • Please upgrade to version 3
Python 3
  • The current version of Python
  • Most packages now support Python 3
  • Has incompatibilities with Python 2
  • Please don’t use Python 2
Python Enhancement Proposal (PEP)
  • Official proposals for enhancing the Python language
Python Package Index (PyPI)
The Python Software Foundation (PSF)
  • Non-profit organization
  • Keeps Python going strong
  • Support them!
Pythoneer
  • A programmer who uses Python to solve problems
  • Styled off the word “engineer”
Pythonic
  • Describes idiomatic code for Python
  • Closely related to conciseness, readability, and elegance
  • Highly recommended
  • Follow style guidelines to learn how to be Pythonic
Pythonista
  • Someone who loves the Python language
  • Often an advanced Python programmer
Sphinx
  • A popular Python tool to generate documentation
virtualenv
  • Tool to create isolated Python environments
  • Enables programmers to use different versions of Python and packages for different projects
  • Also see venv and pipenv
Web Server Gateway Interface (WSGI)
  • A specification for how Web servers forward requests to Web applications and frameworks
  • A core piece of Python Web development
  • See PEP-333 and PEP-3333
The Zen of Python
  • The list of guiding principles for Python’s design
  • Run “import this” to see them
  • See PEP-20