gistfile1.rb

class ApplicationController < ActionController::API

  def status
    begin
      DatabaseHelper::Mysql.smrt.exec_query('SELECT id FROM customers LIMIT 1')
      DatabaseHelper::Mysql.scr.exec_query('SELECT id FROM filter_prefixes LIMIT 1')
      DatabaseHelper::Mysql.backend.exec_query('SELECT id FROM accounts LIMIT 1')
      DatabaseHelper::Mysql.delayed_job.exec_query('SELECT id FROM delayed_jobs LIMIT 1')

      status = Class.new.extend DatabaseHelper
      status.redis.ping

    rescue => e
      Airbrake.notify e
    end
    return true
  end

end

#-------------------------------------

require 'mock_redis'
require 'spec_helper'  
describe ApplicationController do

  before :all do
    @connection = DatabaseHelper::Mysql.scr
  end

  def stub_connection_to_scr method, *data
    @connection.stub(method).and_return *data
    DatabaseHelper::Mysql.stub(:scr).and_return @connection
  end

  it "should return 200 as status"     do
    #mr = MockRedis.new
    RedisConnection.instance.stub(:connection) { raise Redis::TimeoutError, "Connection timed out" }
    expect {reponse = get "status"}.to raise_error ActiveRecord::StatementInvalid   
    response.status.should eq 200
  end


  it "should return 200 as status"     do
    #stub_connection_to_scr :exec_query, "1", "2", "3", "4"
    mr = MockRedis.new
    RedisConnection.instance.stub(:connection) { raise Redis::TimeoutError, "Connection timed out" }
    @connection.stub(:exec_query).and_raise( "Timed out connecting to db")

    reponse = get "status"
    response.status.should eq 200
  end

end