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In this section we're going to write out all the javascript code required to implement this node application.

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Now remember if you're here in this course without a background in node or you maybe you're not interested

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in javascript at all.

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That's totally fine.

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You can skip the section and go to the next section where I've put all the code that we're going to

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write right now.

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They could just copy paste it over very easily.

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So again if you don't want to write out a bunch of javascript just continue into the next section.

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Otherwise stick around and we'll get started right now.

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All right.

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So to get started I'm going to flip back over to my Turnell.

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You'll notice that I'm in in a workspace directory of sorts.

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So I'm no longer inside that web directory that we were working in earlier.

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Inside if you're going to make a new project folder and I'm going to call it how about just visit's

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like so because that's what this application is doing.

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It's counting some number of visits and then going to change into that directory and then I'll open

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up my code editor inside there.

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Now we're going to create two separate files very similarly to what we did on the last application we

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worked on.

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We're going to have a package touchiest on file that's going to record all the dependencies of our application

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and then we're going to have an index such as file which will serve as the actual notes server.

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Let's first make the package not just on file.

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So inside of my project directory I'll make a new file called package Jaison and then inside of here

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we're going to specify some number of dependencies and a scripts section as well.

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So first we'll do our dependencies.

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Don't forget that we are going to use double quotes everywhere inside this file We're going to pull

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in Express and I don't really care what version of Express we use.

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So I'll put an asterisk and then we're also going to get a second dependency that we did not use previously

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called restis.

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Now this read is dependency right here is a javascript client library for connecting to a server.

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So this library right here is how we are going to somehow kind of connect over to our running Retta

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server and pull information from it and update information inside it as well.

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Now for the read us library we are going to use a specific version we're going to get to point eight

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point o.

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So that's the two dependencies we're going to need.

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I'm going to put a comma in and then we're going to add on a script's section as well.

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Very much like we had last time.

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We'll have a single start script and any time we run that it will actually execute node index Geass.

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All right so that's it for our package not just some file.

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I'm not going to make a second file that's going to be indexed.

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J.S. file and that's going to hold all of our actual application code.

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So I'm going to make a separate file called inducts not J S at the top.

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We're going to require in two separate libraries.

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We're going to get express again and then we're also going to import that rightest library that we just

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added as a dependency.

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We'll then make a new instance of an express application.

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And at the same time we're also going to set up a connection to our red S server so I'll say Konst client.

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So client right here is going to represent our connection over to the Retta server I will say redstart

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create clients like so now we're going to come back and add in a little bit more information to this

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create client function call right here.

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We're going to eventually specify the host or we like your L or the address of the server that we're

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trying to connect to in a sport as well.

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But that's going to be a part of a little bit of conversation that we'll have down the road once we

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start to actually put together the Dockers side of this application.

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After that we in a row handler for a route route will say any time that someone comes to the route of

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our application we're going to call this callback function.

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Now inside of here we're going to attempt to use this client's connection over to the Reddit server

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to get the correct number of times that our page has been visited.

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So to do so all say client DOT gets visits and then as a second argument we'll add in a callback that

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gets calls with a possible air object and the number of visits that are stored inside of read us and

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then we'll send a response back to whoever made this original requests we'll just say a number of visits

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is and that will add on through some simple string concatenation.

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Visits like so

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after doing so after sending this response back to the user will make sure that we also update the number

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of times that this page has been visited.

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And so to do so we're going to again reference our client object or say client set visits is going to

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be visits plus one.

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Now a little bit of a gotcha here.

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This visit's variable that we get back from rattus is actually going to come back to us as a string

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rather than the integer that we would really expect it to be.

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And so just to make sure that we add one to an integer and not a string I'm going to wrap this with

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a purse int function call.

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Then the last thing we need to do is out on a lesson will again use port 80 81 and then once the application

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successfully starts listening we'll do a console log that says listening on port 80 81.

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Now one last very quick thing that we need to do inside of here.

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You'll notice that we're kind of assuming that the instant our server starts up we've already got some

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number of visits stored.

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Or like there's some existing initial value for visits that's probably not the case.

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So one thing that we'll do right after we start up our client right here we'll make sure that we do

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a client set visits to zero.

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So this right here is going to initialize our number of visits to be zero.

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And then every time that a user comes to our route we'll pull that number out and then increment it

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by one and store it back on the roadside.

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OK.

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So that's it for this file.

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That's all the application code that we need to right.

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With the exception of a little bit of networking stuff there we're going to put in outside of here to

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make sure we connect to our server.

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So let's take a quick break right here.

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We'll continue in the next section.

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Now we're going to continue working on our docker setup.