In Praise of Non-Fixtured Data

Location: Ballroom A Level:
Average rating: *....
(1.89, 47 ratings)

This talk explores why fixtures are mostly bad, what can be done to “fix” the unmanageable miscreant that fixtures have evolved into, and cross-examines the new breed of data generators.

First, you have to acknowledge that there is a problem with fixtures. You just don’t know it. I’ll show you why you are wrong. If you already want to stab fixtures in the eye socket with a rusty spoon I’m not talking to you.

Second, we will investigate patterns of data generation. These make up the foundation of the libraries examined in the third part of the talk. And finally there will be a fixture replacement shoot-out so to speak. From “roll your own” data generators to the more popular exemplar libraries like Object Daddy, Factory Girl and Machinist, we will decide which one best remedies the fixtures fiasco.

Note: This talk will be given at Scotland On Rails in case O’Reilly does or does not want overlap with regional conferences.

Photo of kevin barnes

kevin barnes

OG Consulting

Kevin R. Barnes
OG Consulting, Inc.

Kevin is a founder and software developer for the boutique software consultancy OG Consulting. He and his partners specialize in Ruby and Ruby on Rails systems with an ever-present focus on the tenets of Domain Driven Design. Over Kevin’s 10 years in the software field he has worked with companies large and small, from the famed Fortune 50 to the nouveau fashionable Fortune 5 million.

In the summer of 2004, he happened upon the enlightened Dave Thomas at a No Fluff, Just Stuff conference who bellowed a blasphemous recommendation, “Try a new language: Like Ruby.” Kevin fell fast for the sleek and sexy language. And soon after chose Ruby on Rails as his web mistress over the Java stack spinster he hesitantly shacked up with years before. Along with his two colleagues, Kevin spoke at RailsConf 2008 on the eccentricities of the enterprise.

Kevin lives and works in Nashville, TN.

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Picture of Paul Hepworth
Paul Hepworth
05/20/2009 10:07am PDT

Day or so? Slides, blog post, anything?

Picture of David Chelimsky
David Chelimsky
05/11/2009 2:50am PDT

Hey Kevin – you planning to post slides?

Picture of kevin barnes
kevin barnes
05/07/2009 12:36pm PDT

I will be posting some technical examples on our blog in the next day or so showing some more detailed examples of model associations and set up for both Object Daddy and Factory Girl. If I have more time I’ll post examples from some of the other libraries as well. I appreciate the feedback.

Picture of Charles Max Wood
Charles Max Wood
05/07/2009 8:50am PDT

I felt that he knew what he wanted to say, but no practical data beyond “fixtures suck” was given at a half hour in. 5 minutes of quick points on why they sucked and 45 minutes on how else to insert test data would have been productive.

Picture of Ryan Schenk
Ryan Schenk
05/05/2009 5:26am PDT

A faster paced presentation would have been better

Picture of Arthur Zapparoli
Arthur Zapparoli
05/05/2009 5:19am PDT

Too much time explaining why fixtures are bad.

Picture of Rob Biedenharn
Rob Biedenharn
05/05/2009 5:15am PDT

Way too long (almost 15 min) to get to the meat of the talk. Needs to have more generator examples sooner—it should be expected that the attendees of a talk with this title will already have used fixtures and are seeking something better.

Mark Yoon
05/05/2009 5:14am PDT

Very slow.

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