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Create Entries
5:27You've configured Sequelize, initialized a connection to the SQLite database, and synced the Article model with the database. In this video, you will work on the routes for data creation.
You've configured sequelize, initialized
a connection to the SQLite database, and
0:00
synced the article model
with the database.
0:04
In this video, we'll work on
the routes for data creation.
0:07
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.
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