Sessionography

This is a simple testing helper for Sinatra sessions. It was written because having to use this sort of approach to test sessions made me sad. Sessionography replaces Sinatra's session helper with a reference to a simple hash in a module variable, enabling session calls that maintain state across requests without the complexity and limitations of trying to use Rack::Session with Rack::Test.

It will not help you sing better. It does not make omelettes. And if you're testing something that actually cares about how sessions get set (e.g., if you're working on Sinatra itself or a low-level Rack component) you won't want to use this. But most of us just want to get on with testing our apps.

$ gem install sinatra-sessionography

(Or sudo gem install if you're the last person on Earth who isn't using RVM yet.)

Then, in your test_helper.rb file or your spec_helper.rb file, just require sinatra/sessionography. If you're using the Sinatra::Base style you'll also need to explicitly include the helper:

# spec_helper.rb
require 'myapp'
require 'sinatra/sessionography'

MyApp.helpers Sinatra::Sessionography

Your app code can continue to call session[:whatever] as it already does. It'll simply bypass any Rack::Session middleware and set a hash in memory.

If you'd like to access that hash in your test cases, there are module methods available:

# This example is in RSpec, because that is how I roll.
describe HypotheticalApp do
  before(:each) do
    # Initialize the session every time. Here we simulate pre-existing state,
    # but you could just as easily assign nil or call .clear
    Sinatra::Sessionography.session = {:foo => 'bar', :too => 'tar'}
  end
  
  it "should do something to the session" do
    post "/something", {:hey => :ho}
    Sinatra::Sessionography.session['hey'].should == 'ho'
  end
  
  it "should pay attention to the session" do
    Sinatra::Sessionography.session[:user] = User.find_by_name('Tina Fey')
    get "/something"
    last_response.body.should =~ /Tina Fey/
  end
  
end

The session will of course persist across Sinatra requests. That's the point of a session. However, it will also persist between test cases, which is probably not what you want, so in your setup or teardown code you should always call Sinatra::Sessionography.session.clear or else set it to nil or some other useful value.

I knocked this off quickly because I needed it (for Sinatra::Flash) but it'd be fairly easy to give it a few other features useful for testing:

• Multiple sessions scoped by name, for simulating interactions between different users;
• Logging or remembering of changes to session state, so that test cases can trace more complex interactions with the session over time;
• Generalization to a Rack::Session::Test (or perhaps Rack::MockSession) component for testing Rack applications outside of just Sinatra.

I don't need any of those today, so I'm not going to build them right away. But if you'd like to see them, feel free to leave an issue here and let me know. (Or just build it and contribute back, of course. The source, it is open like the sky.)

This project is licensed under the Don't Be a Dick License, version 0.2, and is copyright 2010 by Stephen Eley. See the LICENSE.markdown file or the DBAD License site for elaboration on not being a dick.