Creating an HTTP Webserver with Node.js Part 10
Local host port 3000 by default, okay? So just put that there and it's going to print that to the console when we're running. Okay, so now inside here then we're going to do, if it's going to be an html document then usually you want to write the header to say so. So I'm going to say response.writeHead and you can do one of two ways. You can use the head function or you can say the set head and right at the information that's fine too. So when the writeHead takes a few things, as you can see, the first is the status code. So you want to be a 200, I mean it's okay, right? Everything is good and then the next is the content type. So content-type, you can use a key value pair like this. This will be a text/html or you can use to you also use an object like this is fine too. If I do that, then just change that to a colon. So either way should be fine. And then so we're going to write the head for that and then we're going to write a message to the browser. So I'm going to use the write function and then here we use the h1 and I put a message, just say something like, welcome to Node.Js, close my h1. You can see there's a lot of work to titrate because it's a very low level and just make sure that when you were done, you always want to end it. If you don't end it, it's going to be a problem, okay? And that's all we need to do this little short example here, hoops. Okay, so now I'm going to run this code and let's go to the terminal again, you can press the Ctrl back tick, Or go to View and then click on Terminal, take you there. So now I want to go into the demo folder and make sure that I see the app in there. So I do see which is right here, I'm going to run that. And let me clear the console again. So I'm going to go node app.Js, okay? As you can see there are no errors, so we're good to go. This is the link that I added here in my code, right? That's why I wanted to see what's going on so we can know what's happening inside the server and since it's here I can just basically right click or Ctrl click this link here. And should load the browser and we're going to go right to the browser and see. So there's a message, Welcome to Node.js, okay? If you do resource view, right click resource view you see that's exactly what we typed in our source code, okay? So that's how you create a web server. It loads this http local host and port 3000. Now let's go back to the code I'm going to show you something. Again, I mentioned earlier that if you don't close the end function here. So for example, let's just say I comment that out, okay? If I save it again, go to the terminal, I have to restart my server again. So Ctrl+C and then just press up arrow and then running again. I'm going to go back to the browser and I'm going to refresh this page. Okay, so I see the content but you see that this spinning I come up here on the left on the tab, it keeps going, right? So it's causing this app or this page to actually, it's like you're in an infinite loop because it's waiting for this response to end and it doesn't come. So also if you press the Alt key and if you go to the network tab and let's just stop this and do another refresh, okay? So this is spinning again. If you click on the Local host over here on the blue bar, if you mouse over that, it will tell you there's a caution that says request is not finished, okay? So that's why it's really important to end that response. So that means you need to end it otherwise you won't continue on and so we have a blocking issue, okay? So since you are writing a lot of code using the right function, you can do a lot of html here. And if this is the only one that you use, you can use the write function to do that. Well, just in case you might forget to put the end, it's always wise to put that inside the end function instead. So you don't have to use the write function. I can just omit that and ended that here anyway. So it's going to be much safer that way. So I won't forget to end that response, okay? And another reason why you see that, why do you have to save it to a variable server.server? Because I can also change this together to look something like that. You can change it that way and save you some typing. It's either way works fine. If I go ahead and save that and go back to the terminal running it, it should still work. The reason why you save it too it's a variable. Again, if I don't use a variable, I could just do this, it'll work too, it'll work just fine. I put a message here from the Node.Js put a two exclamation marks so we know for sure it's working. Let me save that. Go back to the terminal, I stopped this again and run it one more time in the back to the browser. I'm going to refresh it. And so here's my two exclamation marks. It shows that it does work, right, no problem.