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You've configured sequelize, initialized
a connection to the SQLite database, and

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synced the article model
with the database.

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In this video, we'll work on
the routes for data creation.

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We'll start by including the article model
at the top of the articles.js routes file.

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Require the index file of
the models folder with const

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Article = require,
passing it the path to the folder.

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We can access each model that we define
via a property that gets imported from

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the code in the models index.js file.

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We want to import the article model,
so we'll access it with .Article.

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Now we're able to use the article model
and all the associated ORM methods you've

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worked with before, like find all,
create, update, destroy, and so on.

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The articles.js file contains several
routes to handle HTTP requests,

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like POST and GET.

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The handler functions execute when
a route matches the path defined.

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Since sequelize is promise-based,

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most of the handlers are going to
perform asynchronous actions to

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make calls to the database and
execute all the CRUD operations.

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We're going to use
the async/await syntax for

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all asynchronous calls
made with sequelize.

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And we want to use a try/catch
statement in each handler

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to run the code that needs to be executed
and catch any exceptions that are thrown.

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So because of the necessity
of the try/catch block for

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error handling, our code can
get quite verbose and unwieldy.

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So I'm abstracting away the try/catch
block here in the asyncHandler function,

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which acts as a middleware that wraps each
of our wrap handlers in a try/catch block.

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That way we won't have to
explicitly write try/catch over and

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over again when making
our sequelize calls.

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The catch statement will send a 500 error
or internal server error to the user

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if an exception is thrown in the try
block, or in any of the handler functions.

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You can learn more about the asyncHandler
function in the teacher's notes with

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this video.

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All right, we're ready to work on
getting data into the database.

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You create a new article by clicking the
Create Article button on the main page.

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You can see the server side code for

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this page in articles.js under
Create a new article form.

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When the path is articles/new, the app
renders the new view where the article or

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locals object is an empty object.

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The post route under POST create article
is the route responsible for creating and

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posting a new article.

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Currently it just redirects
to the main articles page.

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So we'll begin here by working
on the creation of rows.

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You've learned that the sequelize create
method builds a new model instance,

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which represents a database row and

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automatically stores its
data in the database.

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Create is an asynchronous
call that returns a promise.

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And inside an async function, you use
the await keyword to wait for a promise.

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So inside this handler function,
initialize a constant

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variable named article
to await Article.create.

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Create requires an object with properties
that map to the model attributes,

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or the ones defined here in Article.init,
for example.

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The request body property returns
an object containing the key value

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pairs of data submitted in the request
body, in other words, the form data.

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For example,
I'll comment out the article variable.

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And if I log req.body to the console,

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notice that it's an object which maps to
the properties of the form inputs and

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the properties associated with the article
model, title, author, and body.

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So we'll pass create
the request body with req.body.

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When the database builds and
saves the new article record,

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the app should redirect to
the newly created article.

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Sequelize generates an auto-incrementing
ID for each model instance or

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entry created.

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So in the res.redirect method,
I'll add the article id to

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the URL path by concatenating
article.id to the articles path.

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Over in the browser,
I'll click Create Article,

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then type some sample data in
the Create New Article form.

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When I click Submit,
I'm redirected to the URL path articles/1.

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The article data does not render
to the view since we're not yet

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retrieving the data from the database.

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We'll do that in the next video.

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But I'll quickly check if the new
entry was added to the articles table,

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using the DB Browser for SQLite app, which
you may have used in a previous course.

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I'll open the development.db
file in the app.

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And clicking Browse Data shows
the new article entry with an id of 1.

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We see the title, author, and body data,

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as well as the timestamps
generated by sequelize, it worked!

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In the next video,
we'll start reading from the database.

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That way we'll be able to view all
the articles on the main page and

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individually by their ID.