Posted by sam, Thu Feb 21 02:04:18 UTC 2008

I've started using rSpec at work for my project. I like it because it just seems better to use than Test::Unit. It also looks nicer.

Anyway, my project at work involves converting data from and old database into a new one by way of CSV files. Its long and tedious, and there are hundreds of thousands of rows hitting several models involved.

Inevitably, something will bomb during the process. I've I've developed a process where I can selectively extract a participant based off of their employee number and create a folder filled with their csv files. However, I wasn't really doing any testing on it at this point. We're using rSpec for model testing, and after watching the rSpec User Story PeepCode, I decided to give it a whirl for on my file conversion process.

I start my file conversion process on a single employee by invoking a rake task. It's basically a batch job.

rake conversion:selective_import id=12345

In order to set this up via rSpec stories, first you need to set up the rspec helper file located in RAILS_ROOT/stories/helper.rb. Insert these lines.

require 'rake'
require 'rake/testtask'
require 'rake/rdoctask'
require 'tasks/rails'
load "lib/tasks/conversion/tables/001_employee.rake

You need to manually load a the rake tasks you need for some reason I haven't figured out yet.

Next up, in the story's .rb file, you need to make it look like this

require File.expand_path(File.dirname(__FILE__) + "../../../helper")
with_steps_for(:conversion) do
  run File.join(File.dirname(__FILE__), "conversion_story"), :type => RailsStory
end

Astute readers may wonder why the file is buried so far down: I'm trying to create many stories and i'm organizing them by folder. Here's the edited output from tree

|-- all.rb
|-- helper.rb
|-- scenarios
|   |-- conversion
|   |   |-- conversion_story
|   |   `-- conversion_story.rb
`-- steps
    `-- conversion.rb

My conversion steps look like this:

steps_for(:conversion) do

  Given "a employee number $employee_number" do |employee_number|
    @emp_no = employee_number
  end

  Given "is extracted" do
    #look for the employee's extract in the folder
    #if you dont find it, then run the extraction task
  end

  When "I nuke the database" do
    Rake::Task['conversion:nuke'].invoke
  end

  When "I nuke the employee" do
    ENV['id']=@emp_no
    Rake::Task['conversion:selective_nuke'].invoke
  end

  When "I reset the employee" do
    ENV['id']=@emp_no
    Rake::Task['conversion:selective_reset'].invoke
  end

  When "I convert the employee" do
    ENV['id']=@emp_no
    Rake::Task['conversion:selective_import'].invoke
  end

  Then "there should only be 1 employee" do
    Employee.count.should == 1
  end
end

Obviously, the code at this point is a work in progress, but so far, so good.

Here's the story

Story: File conversion test

    As a user
    I want to convert an employee with 
    So that I can verify that their is only one

  Scenario:  42582

    Given an employee number 42582

        When I nuke the database
        And I convert the employee

        Then there should only be 1 employee

I hope all of you have enjoyed this rSpec tutorial with Rake.

Filed Under: | Tags: rspec ruby