We've created and red rows of data within our route handlers.

And this video will continue to update the articles that JS routes file,

this time working on the routes for updating and

deleting articles, updating and deleting entries is a two step process.

First, you retrieve the entry to update or delete from the database, then once you

found the entry, performance a sequalize update or destroy operation on it.

Let's begin by updating an entry.

We'll work with the get method route that renders the articles edited view.

Which displays a form to edit the article specified by the ID URL parameter.

Then we'll work with this http post route, which updates the article in

the database and redirects to the updated article on form Submit.

Right now it just redirects to the article's URL path.

First, I'll use the findByPK

method in the edit article route to find the article to update.

I'll initialize an article variable to await article.findByPK.

And I'll once again pass findByPK ID of the article to edit using

the id route parameter, with req.params.id.

Currently, the article or

locals object passed to the the article's edit view is an empty object.

Once the article to edit is retrieved we can pass its data

into the view by setting the article property to the article variable.

Since they're the same, I can pass it just article.

Next, the Post method route here will perform a post

request to the articles ID edit path to update the entry.

If you have a look at the articles, edit.pug view, you can see the form action

and method attributes used to send the form data from the client to the server.

I'll first find the entry to update by its primary key,

then update the article in the database using sequilizes update method.

And the handler I'll again initialize an article

variable to await article.findByPk passing it req.params.id

The update method is also asynchronous and returns a promise.

So in the async handler we'll await its fulfilled promise,

the updated article instance with await article.update

The update method accepts an object with the key and values to update.

So I'll pass it the request body or the updated form data with req.body.

Once the update happens,

the app will redirect to the individual article page via article.id.

Back at the app,

I'll test the latest updates by clicking Edit Article on the first article.

This brings up the Edit Article form with the content to edit,

I'll update the title, for example, click Submit and see that it works.

Next, I'll work on deleting entries.

There are two routes that deal with deleting an article in articles.JS.

When you click Delete Article, you're presented with a delete article form

to confirm that you want to delete the article.

The route that renders this view is the delete article form get method route.

Then there is the post method route that actually deals with deleting the article.

So, first, in the get method route, I'll again use SequlizersfindByPK

method to find the article to delete by its primary key or ID.

I'll declare an article variable and

sign it await Article.findByPk

(Req.params.id).

Once the article to delete is retrieved pass its data into

the articles delete view by passing in the article object.

Just below in the Post method route,

I'll find the article to destroy also by its primary key.

With const, article goes await Article.findByPK.

Passing it req.params.id.

Once the article is found I can destroy it.

The destroy method is also an asynchronous call returning a promise.

So the handler will await.article.destroy.

Once the promise is fulfilled or the entry is deleted from the database,

the router will redirect to the articles path.

All right, I'll test the latest

updates by clicking to read an article.

Then clicking Delete Article, I'm presented with the Delete Article View

displaying the article title and the actual delete button.

Click the button and it worked.

I'm redirected to the main articles page and the deleted article no longer appears.

All the cred operations are complete, but we haven't handled errors.

For example, display a validation error

if a user leaves a field empty when creating or editing an article.

Also general errors like if a record is missing or

if any other unforeseen errors occur.

So in the next step, you'll add validators to the article model to prevent invalid

data from being entered into the database and display validation errors to the user.