Running a rack app in a thread for integration tests.

http_client_spec.rb

require 'integration_helper'
require 'rack'
require 'rack/handler/webrick'

describe HttpClient do
  before :all do
    @server = WEBrick::HTTPServer.new(
      :Port      => 9293,
      :Logger    => Rails.logger,
      :AccessLog => Rails.logger
    )
    @server.mount '/', Rack::Handler::WEBrick, lambda {|env|
      requested_response_code = env['REQUEST_PATH'][1..-1].to_i
      [requested_response_code, {}, ['{}']]
    }

    Thread.new do
      @server.start
    end
    start_time = Time.now
    while !listen_on_port?(9293) && Time.now < start_time + 1.second
    end
    raise "Could not start server" if !listen_on_port?(9293)
  end

  after :all do
    @server.shutdown
  end

  let(:http) { HttpClient.new("http://localhost:9293/") }

  shared_examples_for 'an http method' do
    it 'raises FailedRequest for non-successful requests' do
      lambda { perform("/404") }.should raise_error(HttpClient::FailedRequest)
      lambda { perform("/500") }.should raise_error(HttpClient::FailedRequest)
    end

    it 'does not raise for successful requests' do
      lambda { perform("/200") }.should_not raise_error(HttpClient::FailedRequest)
    end
  end

  describe '#get' do
    def perform(path)
      http.get(path, {})
    end

    it_should_behave_like 'an http method'

    it 'should return response with body' do
      perform('/200').body.should == '{}'
    end
  end

  def listen_on_port?(port)
    `lsof -i :#{port}`
    $? == 0
  end
end

As I understand it, I could use a similar thing to measure the boot time of raptor, correct?

(measuring boot time as: fork off a shell running rackup, send an http request at it, check it returns some value, then shutdown)

If there's no dynamic loading, you can just start it up with a flag to auto-quit, no need to actually hit it (I use rails runner for Rails apps).

Thank you, this really helped me out. After I made it work, I assembled a bit simpler way how to write it:

require "timeout"
# ...
    @server = WEBrick::HTTPServer.new(
      :Port          => 9293,
      :StartCallback => -> { @started = true }, # <--------------------
      :Logger        => Rails.logger,
      :AccessLog     => Rails.logger
    )
    @server.mount '/', Rack::Handler::WEBrick, lambda {|env|
      requested_response_code = env['REQUEST_PATH'][1..-1].to_i
      [requested_response_code, {}, ['{}']]
    }

    Thread.new { @server.start }
    Timeout.timeout(1) { :wait until @started } # <--------------
# ...