- What is Express? 4:05
- Install Express 4:28
- Review Installing Express 1 objective
- Review: Installing Express 5 questions
- Creating a Server in Express 3:23
- Creating a Route with Express 6:55
- Review: Your First Express App 5 questions
- Adding Multiple Routes to the App 4:34
- Setting Up a Basic Express App 2 objectives
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Creating a Server in Express
3:23Learn the basics of setting up a server with Express.
In this video, I'll teach you how to
setup an Express server from scratch.
0:00
Here's the app it has one page and
it says, I love Treehouse!
0:05
And that's it believe it or not,
0:10
this simple app contains all the basic
components of an Express application.
0:12
Express sets up its server, a server is
a program that runs on a remote computer.
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Its job is to wait for
HTTP requests from clients.
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Request is a technical term for
0:30
what is happening when you
type in a URL into a browser.
0:32
Your browser is making a request to
a server at the URL address you typed in.
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When a browser, or client,
makes an HTTP request to the server,
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the service brings into action
putting together a response.
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The development process requires you,
0:53
the developer, to test and
build a web application.
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It's usually much easier to run an
application server on your local machine.
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This means you'll have both a server and
a client on your computer.
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You'll use a browser to test
the server in one window, for example.
1:10
And then see the server
respond in another.
1:14
Later, when your ready to make your
application available to the public.
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You'll need to deploy it to a remote
server, where other people can visit it.
1:23
Deploying a web application is
beyond the scope of this course.
1:29
But check the teacher's notes for
more information.
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Let's set up the express server now.
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Here's my text editor with the code
I left off in the last video.
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We have already required
the Express module and
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assigned it to the variable Express.
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Let's create our app.
1:50
To create an Express application
we can just call express.
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The express function returns
an Express application.
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Let's assign the Express application
to a new variable called, app.
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This app is the central
part of our application.
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We'll extend it throughout this course
by adding routes, middleware, and
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other settings.
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The first thing we're going to do
is setup the development server
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using the listen method.
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I can give this one parameter
which is the port number 3000.
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Believe it or not, we have an Express app.
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This code will create a server, and when I
run it, the server will run on my machine.
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And I can send it requests through
a special URL called localhost.
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Let's see what this looks like.
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I could start the app
by running node app.js.
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The prompt is gone because the server
is busy listening for requests.
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Now in my browser,
I can type localhost and
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then specify the port:3000 and hit Return.
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I can see an error message from Express.
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This is a good sign because it
means that Express is running and
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it's sending a response.
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The error is coming from the fact that I
3:16
have not told Express how to
respond to any requests yet.
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