Yesterday we were deep in the middle of coding using RSpec 2 and Rails 3 and needed to verify that a method made a specific http request. I happily discovered WebMock, which appears to be a next generation FakeWeb. Originally developed by Bartosz Blimke, I was happy to see that Sam Phillips had it working with Rspec 2 and Rails 3.

I found the following posts helpful:
RSpec 2 on Rails 3
using bundler with Rails 3

Here’s what I did to set it up (using rvm, which I highly recommend):
[code]
rvm gemset create rails3
rvm use 1.8.7@rails3
gem install rails --pre
gem install rspec-rails --pre
gem install sqlite3-ruby
rails rails3_webmock
cd rails3_webmock/
vi Gemfile

group :test do
gem "rspec", "2.0.0.beta.8"
gem "rspec-rails", "2.0.0.beta.8"
gem "webmock", :git => "git://github.com/samdanavia/webmock.git"
end

rails g rspec:install
exist lib
create lib/tasks/rspec.rake
exist config/initializers
create config/initializers/rspec_generator.rb
create spec
create spec/spec_helper.rb
create autotest
create autotest/discover.rb

bundle install

add these lines to spec/spec_helper:
require 'webmock/rspec'
include WebMock
[/code]

We wrote the following little test to test how to write a spec that verifies that an http request happens:

[code]
require 'spec_helper'

class Thing
def self.call(uri_string)
uri = URI.parse("http://www.google.com")
result = Net::HTTP.get(uri)
end
end

describe Thing do
it "should call a net API" do
uri_string = "http://www.google.com"
stub_request(:get, uri_string).to_return(:body => "something")
Thing.call(uri_string).should == "something"
WebMock.should have_requested(:get, uri_string)
end
end
[/code]

I put it in spec/lib and can run it with:
[code]
spec spec/lib/thing_spec.rb
[/code]

Note: I don’t need to call “bundle exec” with rspec to ensure that I use the versions specified in the bundle. [Update from@wycats spec_helper loads config/environment.rb which loads application.rb which calls Bundler.setup -- nice.]

Special thanks to @zakkap for the opportunity to dive into Rails 3 on a real project.