## What is Resque?
* Handles background jobs by placing them on queues and handling them at a later time
* Useful for code that is being executed on an external web service that can be moved into a
background task
    * Why?
        * The service could take up time and cause delay in your app's loading time
        *  You want to move them into a background process
        *  Also prevents the blocking of other requests from one that is currently being held

## Setting up Resque
* install or have installed redis!!!
* start the redis process!
* In `Gemfile`: add `gem 'resque'`, then run `bundle install`
* Add a file within `lib/tasks`, called `resque.rake`

```ruby
require 'resque/tasks'

#load the environment when the worker starts up
task "resque:setup" => :environment
```

* run this in the terminal **after all changes have been made to the project**:
`bundle exec rake resque:work QUEUE='*'`
* The `QUEUE=''` takes in the name of the queue to work on or use `*` to load all queues
* You can now move your API request code in to a **worker** file
* Use `Resque.enqueue(workerClassName, additional_arguments)` to move the API request code to a
worker file. Additional arguments could be `@object.id` (can be use to refetch the object without
submitting a complex object that is going to be turned into JSON).
* Create a new directory within `apps` called `workers`
* Create a file (worker) in the `workers` directory and name it using the `worker_class_name.rb`
used in the `enqueue` line above.
    * That worker file is basically a **ruby class**!

    ```ruby
    class WorkerClassName
      # 1st requirement
      @queue = :name_of_queue       #can be named anything

      # 2nd requirement
      def self.perform(object.id)      #takes the additional arguments passed in to enqueue
        object = Object.find(abject.id) #refetch the id that was before to complex to send through
        ... #code referencing your API call!
      end

    end
    ```

* Complete!

## Resque Web Interface
* from terminal, execute `resque-web`
* You can check the queues and failed jobs!
* **May need to restart rake task if new code was added after running the task initially**

## Imbedding the Web Interface into your App?
* You can add a route to also visit the resque web interface instead of launching it from terminal!
* In `config/routes`: `mount Resque::Server, :at => "/resque"`
* Need to edit the `Gemfile` again: `gem 'resque', :require => "resque/server"`

## Add authentication to the Resque Web Interface
* If using `Devise`:

```ruby
#routes.rb
authenticate :admin do
  mount Resque::Server, :at => "/resque"
end
```

* If not using `Devise`, an alternative way is to create a new `initializer` in
`config/initializers` called `resque_auth.rb`

```ruby
Resque::Server.use(Rack:;Auth::Basic) do |user, password|
  user == "rtrw"
  password == "jhtrw"
end
```