我的网站如何知道连接到我的 Node 应用程序？

Question

If I have Node app running on Heroku and it creates a server and listens to say port 80. How does my website know to interact with the code in my node.js app?

Essentially, I am trying to send an object created on my client side with Ajax to the server-side. How can my node.js app listen for this data, especially in production?

More info:
So I have a static website view with html and css uploaded through shared hosting. I am trying to implement a simple payment system through Stripe using Node.js. So I only have one server for Node and a shared host for my website. My question was how can I connect the two without having to serve the .html files through Node?

Answer 1

It's unclear exactly where you got stuck in setting up your node.js server as pretty much everything you've asked for is explained in many examples on the web. So, since I don't know where you got stuck, I'll explain conceptually the steps you go through to field an Ajax call from your site:

1. Set up your node.js server listening on a unique port on a host that is in DNS. Since this is a different server than your website, it will need to either be a different host or a different port (if on the same host).
2. Enable CORS in your node.js app so that your node.js server will let the browser do cross origin requests to it. There is an NPM module that can make this pretty easy for you.
3. Set up the shell of your node.js web server. I would personally use Express to make it simpler.
4. Create a request handler in your server for a "post" on a particular route. This will allow your web server to listen for a specific request.
5. Write the code in that request handler that parses the request and does whatever it is you want to do with the request.

FYI, if the only think you were going to do with your node.js server is use Stripe checkout, then you may be able to write Javascript in your web page that communicates directly with the Strip service without evening having your own node.js server. It depends upon the details of what you're trying to do. Some Strip checkout details here: https://stripe.com/docs/checkout

Answer 2

Because you declare your routes (assuming you're using something like Express or you've made your own vanilla http server) so when you visit a route it knows to execute whatever function you've tied this too

eg app.get('/', someController);

knows that whenever somebody visits / it will make someController execute.

Node directly runs the website through your program its self and knows these things

If I misunderstood let me know

Reply to comment:

I'm not quite understanding your question, if you upload your view files eg your home.ejs/html/jade whatever you're using to another server, then upload your app to another server, it won't work you'll get 404 not found or something. I'm assuming you came from PHP or something where you have your PHP files and everything is combined like you have your html/php in one file and then when you visit your localhost/home.php it works. Node is different you have your app which through your server side logic you tell it what view to call, your client side stuff (like your views and css/js and what not) are completely separate from your server side logic, and through your controllers, you tell what function to call what view, eg

(assuming you're using express) You have this as a controller:

app.get('/', function(req, res) {
  res.render('home');
});

then in your app.js logic you have:

// Your Route
app.use('/', homeController)

Then in your views you probably have

home.html/jade/ejs (extension depending on whatever templating you're using)

now when somebody visits / the route see's this and goes ok I need to call the homeController and so it does and it's happy, then it gets the content of the function and goes oh it wants to render a view file which then express' function res.render will map over your views folder until it finds something that resembles whatever you've requested, in this case: home.html so it then renders the file and sends the response back to the client,

So in short Request > Route > Controller > Function Body > Does whatever you've programmed from there

Long story short, your client side stuff and your server logic are completely independent from each other

As where with your PHP or something, you have your php file

<?php

<html>
</html>

?> (i think thats how it goes I haven't done php in a looooonngg time)

and then you run apache or whatever and apache will magically route to the .php file requested, compile and render it

I hope I answered a little better