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Now, let's dig a bit deeper into Node.JS.

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We've got some basic Node.JS code here,

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but of course this code isn't doing too much.

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What I wanna do now is I wanna support a brand new path

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in my URL.

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To be precise,

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I wanna make sure that if we enter our domain,

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so in our case, localhost,

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and then the port, /currenttime,

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I wanna show a current timestamp on the page.

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If we enter just localhost:3000.

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So basically, localhost:3000/ nothing, you could say.

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The slash doesn't really make a difference here.

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Then, I instead want to show this Hello World!

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or welcome page.

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So I wanna send back two different kinds

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of responses based on the path, as this part is called here,

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that is entered in the URL.

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Now, of course, we did already send back different responses

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before in the course when we worked

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with different HTML files.

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Then, we were also able to enter slash

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and then the HTML file name to load different HTML files.

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But the whole idea of getting started with Node.JS is

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that we see that we can now actually have full control

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over the response that is being sent back

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and that we no longer need to create HTML files

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as responses, but that we can control the response

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with Node.JS and JavaScript only.

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And then, in the next sections,

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we are going to reintroduce HTML files,

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but then we'll also write them such

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that they are a bit more dynamic, but more on that later.

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So to handle these two different paths here

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in this handler request function,

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we now can extract some extra data from this request object,

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which we get automatically.

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This request object actually has a URL property.

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It will have that URL property because this object,

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which we get is created by Node.JS,

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and it is created such that it has such a URL property.

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And the URL property actually will not hold the full URL,

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but it will hold this part.

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So the part after our domain and port.

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And therefore, we can now use this request.url property

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in an if statement and check if request.url is equal

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to /currenttime so that we then,

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inside of this if statement,

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can write the code that should execute

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if a request is sent to that URL.

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And else, if a request is sent to a different URL,

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or maybe else if, if we wanna be more specific,

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if request.url is equal to just /,

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so just our domain with nothing after it,

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that's represented by just /,

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then I wanna execute different code.

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And then, we could move this code here and move that

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into this else-if branch and auto format this code.

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And here I can still say Hello World!

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But then, I'll also copy this and added here inside

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of this first bronch.

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And then, here, I can sent back a different piece

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of information.

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I might still want to create a h1 tag here,

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but I actually wanna create it such

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that I can insert some dynamic data into it,

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because that's one of the main reasons

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for using Node.JS, or for using a programming language

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that executes on the remote machine.

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I want to be able to send back different responses

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that might contain dynamically fetched or generated data.

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And that's what I wanna simulate here.

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Between the opening and closing h1 tag here,

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in this if branch, I want to output the current timestamp.

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And I can do this by injecting something

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between these two strings, a third string,

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which is the current timestamp.

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And in JavaScript, both on the browser side and in Node.JS,

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we can get that current timestamp by using new Date,

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which creates a date object.

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And on this created new Date object,

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we can call toISOString to convert this date object

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into a string representation, so into some readable text.

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toISOString is a method which we can call

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on that created new Date object.

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And new Date simply is a built-in way of creating

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such a date object.

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Now with that, if we save everything,

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we have two different URLs we can target

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and we'll get different responses.

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So if we now open this terminal again,

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and here I did that with the shortcut,

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you can, of course, still also do it manually.

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You can see the shortcut if you go to Preferences,

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Keyboard Shortcuts.

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Here, I'll then again execute this app.js file

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with node app.js.

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This process then keeps on running as learned.

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And now, if I visit localhost:3000,

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I still get Hello World!,

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because that is basically localhost:3000/ nothing.

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And that is this second branch here.

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If I enter localhost:3000/currenttime though,

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then I get this current time snapshot.

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Of course, it's not formatted in a super pretty way,

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but it's good enough for the moment

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and it proves that this works.

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If I enter anything else, like /something,

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instead, we'll get an error.

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This will keep on loading, and ultimately, it will crash,

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because this function executes

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but never produces a valid response.

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And therefore, ultimately,

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this request will time out because it never gets a response.

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You might wanna handle such scenarios as well,

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but here we'll just ignore it and focus on the two cases

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that do work.