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VAMPIRES

The CR in CRUD

CRUD is an acronym for Create, Read, Update, and Destroy-- these are the fundamental actions we perform on data.

Tonight's homework is to make an app that will both Read and Create data for a single model (Vampires). Update and Destroy will come later.

APP

The app will have an index page, a show page, and a new page. It will also have a create route.

Index: all of the vampires are displayed on this page (just the images, they are 300 x 300 px).
Show: one particular vampire is displayed on this page.
New: a form for creating a new vampire is displayed.
Create: this is a POST route that adds data to the Vampires array (it does not have a webpage, instead it redirects)

The app will show a list of vampire images. You click on 'em, they go to a show page.

The app will also be able to store new vampires. You click on a 'new vampire' link and a new vampire is resurrected from obscurity and will appear on the index page.

DIRECTIONS

Make a new Express app called vampires.
Run npm install to install all the dependencies that are already in package.json.

Controllers

Make your index and show routes for the vampires in the vampires model.

  - URI convention for index: GET `/vampires`
  - URI convention for show: GET `/vampires/:id`

Make a new route. All this should do is render the new view, you don't need to pass it data.

  - URI convention for new: GET `/vampires/new`

Place your new route above your show route, or the user will never get to it (they will always go to the show route instead). Can you explain why this might be?

CREATE and req.body

Make a create route.

  - URI convention for create: POST `/vampires`

This will add the data sent from the new form into the Vampires array, and redirect to the index. This new data will come from the request object-- inside another object called body. Does req.body exist without body-parser? Well no. body-parser adds in an empty body object to the request object that can later be populated with data. You can test the existence of req.body by console.logging req.body.
- You will need to set up body-parser in your server.js.
- Once you have required body-parser, this is the code to get it to work:
```
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());
```
Note that you can find this code in the body-parser docs on the npmjs site.

Testing POST requests

Network Tab

You can see the POST request go through in the Network tab in the Chrome console. Open up the console, hit the submit button for the request, and you will see the requests load. Click on the POST request, select the Headers, and scroll down to the bottom where you will see the form data.

This is good way to see if the form data has even been passed through the browser.

Postman / cURL

You can use Postman or cURL to send data to a server. Send data with Postman or cURL to your POST route, and set up the route simply to console.log req.body to see if the data has reached the server.

Sample curl request:

curl -X POST -d key=value -d key2=value2 http://localhost:3000/vampires

Sample route to check if data has arrived:

app.post('/vampires', function(req, res) {
	console.log("HERE IS THE DATA: ");
	console.log(req.body);
	res.redirect('/vampires');
});

Views

index.ejs should just be a clickable image of each of the Vampires. Note that the images in the model are the same size (300 x 300 px each) to avoid resizing. Each image should link to the show page for that Vamp. There should be a link to add a new Vampire.

show.ejs should display the Vampire's name, image, location, gender, and number of victims. There should be a link to return to the Vampires index.

new.ejs should render a form where the user can enter a new Vampire's name, location, gender, number of victims, and url of an image. The form will submit to the create route.

NOTES ON FORMS

The name of each input box should exactly match the corresponding key name within the model. In the Vampires model, img is the key that stores the image url. Therefore, in your form, the name of this input should also be img. Example:

<form action="/vampires" method="POST">
	<input name="img" placeholder="image url">
	<button>Submit new vampire</button>
</form>

When this data is sent to the back-end, you won't need to change the name of your data to fit your model.

NOTES ON RESTFUL ROUTING

There are seven RESTFUL routes, but tonight we are only using four.

VIEW routes (GET):

index displays an index of all resources.
show displays just one resource.
new provides a form for adding a new resources.
edit provides a filled-out form for an existing resource.

The routes that have views are sent from a GET request.

REDIRECT routes (POST, PUT, DELETE):

create takes the data from the new form.
update takes the data from the edit form.
destroy removes data.

The routes that have redirects are sent from POST, PUT, and DELETE requests.

 In an app with full RESTFUL routes, you will have **four** views and **three** redirects.

 Later on, you could of course combine views to reduce navigation, but for now, there are four.

 Tonight's homework will use three of these views, `index`, `show`, and `new`, and just one redirect, `create`.

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