# Controllers

## Generating Your Controller

Now that we have created our application, our next step is to create our controllers. Controllers define the business-logic of the Blueprint application, and are a composed from group of actions. The actions of a controller are responsible for servicing requests from clients. 

If we look at the original [super-rentals tutorial](https://guides.emberjs.com/release/tutorial/installing-addons/#toc_ember-cli-mirage), the mirage component of the tutorial defines the single route `GET /api/rentals`. This means that we need an action to handle this HTTP request from the client.

First, let's define our controller. We are going to name the controller `rental` since it will be responsible for all business logic related to rentals.

```bash
blueprint generate controller rental
```

{% hint style="info" %}
Make sure you run the Blueprint cli from the Blueprint application directory. In this tutorial, you must run the Blueprint cli from the `./super-rentals` directory.
{% endhint %}

This command will generate an empty controller (*i.e.*, a controller with no actions) named `rental` in the `./app/controllers` directory.

{% code title="app/controllers/rental.js" %}

```javascript
const {
  Controller,
  Action
} = require ('@onehilltech/blueprint');

/**
 * @class rental
 */
module.exports = Controller.extend ({
})
```

{% endcode %}

## Implementing the Action

We can now add our single action to the `rental` controller that will get the rentals when requested by a client. The action we create will return the [same data as the EmberJS super-rentals example](https://guides.emberjs.com/release/tutorial/installing-addons/#toc_ember-cli-mirage).

{% code title="app/controllers/rental.js" %}

```javascript
const {
  Controller,
  Action
} = require ('@onehilltech/blueprint');

/**
 * @class rental
 */
module.exports = Controller.extend ({
  get () {
    return Action.extend ({
      /**
       * The execute(res, res) method is an abstract method that must be 
       * implemented by all Action subclasses. The execute(req, res) method
       * is responsible for handling the request by sending a response to
       * the client.       
       */
      execute (req, res) {
        res.status (200).json ({
          data: [
            {
              type: 'rentals',
              id: 'grand-old-mansion',
              attributes: {
                title: 'Grand Old Mansion',
                owner: 'Veruca Salt',
                city: 'San Francisco',
                category: 'Estate',
                bedrooms: 15,
                image: 'https://upload.wikimedia.org/wikipedia/commons/c/cb/Crane_estate_(5).jpg'
              }
            },
            {
              type: 'rentals',
              id: 'urban-living',
              attributes: {
                title: 'Urban Living',
                owner: 'Mike Teavee',
                city: 'Seattle',
                category: 'Condo',
                bedrooms: 1,
                image: 'https://upload.wikimedia.org/wikipedia/commons/0/0e/Alfonso_13_Highrise_Tegucigalpa.jpg'
              }
            },
            {
              type: 'rentals',
              id: 'downtown-charm',
              attributes: {
                title: 'Downtown Charm',
                owner: 'Violet Beauregarde',
                city: 'Portland',
                category: 'Apartment',
                bedrooms: 3,
                image: 'https://upload.wikimedia.org/wikipedia/commons/f/f7/Wheeldon_Apartment_Building_-_Portland_Oregon.jpg'
              }
            }]
        });
      }
    })
  }
});
```

{% endcode %}

That was quite simple!

## Next Steps

Now we have a controller that defines an action to respond to client requests for rentals.� Our next step is to define a route that invokes this action.


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