I'm really confused with reverse proxy. What i understood is in forward proxy the client know the destination server but the server doesn't know the client, in reverse proxy the server knows the client but the client doesn't know the "server" he's visiting is a actually proxying to some other server. And to use the reverse proxy you can use NGINX. But if we can use that, why do express framework middlewares like http-proxy-middleware
exist?
and if my understanding of proxy and reverse proxy is wrong please correct me
Lets take an abstract example:
You will agree that you must be using port 3000 or something to run NodeJS... Right?
And lets say you also use angular/react or html+css to run your frontend website which is lets say on port 4200 (default for angular).
Now what if you want to have only one server and want two different services (frontend in angular and backend in nodejs) to run on that single server only.
So you need something in between your client and server to distinguish between the requests whether to forward them to angular or nodejs or any other service as well that is running on the same server.
What reverse proxy such as NGINX will do is you will define some rules on the basis of which the administrator of the server can utilize same server to serve various services.
This is the simplest example I can think of on the top of my head.
Related
A typical request gets processed like this:
request -> Nginx reverse proxy -> AWS EC2 -> Express API/FastAPI -> response
but my biggest confusion is why a FastAPI absolutely NEEDS Nginx to work, but an Express API doesn't (despite nodejs and python both having the http module and hence able to make web servers). Why do I need Nginx at all for FastAPI? Can't an AWS EC2 instance act as a web server like Nginx?
This post says it is so we can hide the port number in the url, but that being the only reason sounds unreasonable to me.
Why is a web server (i.e Nginx) REQUIRED for FastAPI
Nginx is not required for FastAPI. You can listen on external ports and handle requests without a reverse proxy. Even FastAPI documentation includes setting up Nginx under the Advanced section (Ref)
This post says it's so we can hide the port number in the url, but this being the only reason seems silly to me.
You can still hide the port number in the url if you run the Express app with sudo and listen on port 80 or 443.
Can't an AWS EC2 instance act as a web server like Nginx?
Yes it can.
There are benefits of using a proxy server like Nginx. Proxy servers can handle load balancing, caching, SSL termination and they can handle large number of concurrent connections efficiently.
Using a proxy server is a best practice. However, it is not a requirement for FastAPI or Express.
1 With different apps different website domain etc, NodeJS cannot go to production with host:*some port other than 80*, right? If I am wrong, how to deal with NodeJS apps with multiple website on the same machine? ( there is no virtualhost in NodeJS/Express server, isn't there?)
2 So the solution to go prod to me, only alternative is to use some proxy forwarding requests to the NodeJS/Express server IP:port, isn't it? If yes and if it is a different server ( proxy and NodeJS), what does express to start and listen to? (Say, server.listen('port', '0.0.0.0') or server.listen('port', '::')?
3 Any other alternatives to go production with NodeJS/Express projects?
You can use 80 but with sudo. However, it's not recommended.
You're right you need a proxy (nginx, haproxy, etc..) to sit in front of your Node.js app in order to use port 80.
I think you can omit host from server.listen so it will accept connection from ::.
NGINX is the best option to do, what you expect and see the NGINX documentation in official web site.
I have read that proxies can be created by Nginx server for nodejs application to listen on but I am doubtful as to what exactly this will serve additional purpose and advantages compared to http module provide by nodejs for listening purpose.
For one, you can serve multiple Node applications on one server, with host based virtual servers managed by nginx, so that requests to the same port but with different Host: HTTP header reach different Node applications.
Also nginx can be set up to serve static assets without hitting your Node app and do some caching if you need it.
Those are two things that you can achieve with adding nginx to the mix but you may not need that in your case. Also, you can run a reverse proxy with Node and without nginx if that's what you prefer.
I'm setting up a node.js server but I would also like to have Apache running on there at the same time. Node is going to be the main website, and there will be subdomains that point to Apache.
The only way I can think of how to do this is have the different applications listen to different ports and then have a proxy application that listens to port 80 and then "redirects" the port according to the subdomain used. I'm not sure if this is the right way to do it, or how to do it if it is.
Research has shown me that it could be possible to use Apache as this proxy, though I would prefer it if I didn't have to. If I could somehow use node.js to do it, that would be fantastic (my preferred solution). If that is impractical/impossible, then of course I am open to other ideas.
I would really appreciate some guidance as to how to do this.
You wanted a solution that can serve both Node.js and Apache at the same time, and you wanted to have Node.js to do the reverse proxy. However, it is best to use a program that is designed for reverse proxy (Nginx, HAProxy) for that job. Using Node.js as a reverse proxy server will be inefficient.
Nginx is something I recommend. It is simple and highly efficient. You can have the Nginx server at the very front, taking in all the requests.
Here is how you setup Nginx to reverse proxy to Node
http://www.nginxtips.com/how-to-setup-nginx-as-proxy-for-nodejs/
And here is how to setup Nginx to reverse proxy to Apache
http://www.howtoforge.com/how-to-set-up-nginx-as-a-reverse-proxy-for-apache2-on-ubuntu-12.04
Simply combine the setting files of the two will enable you to serve apache and node at the same time.
Have a look through this thread
While it discusses some issues using http-proxy with WebSockets on <= 0.8.x, if you aren't doing that, you should be fine.
You can create a very basic proxy listener like so:
var http = require('http'),
httpProxy = require('http-proxy');
httpProxy.createServer(8888, 'localhost').listen(80);
And create a back-end server like so:
var http = require('http').listen(8888);
But of course, more complex implementations can be accomplished by reading the http-proxy documentation.
I want to ask about some good practices. I have a Node.js (Express) web server and socket.io push server (in case technology matters). I can turn both of them into one application but I want them separated (they can communicate with each other if necessary). There are two reasons to do that:
It will be easier to manage, debug and develop the app;
It will be a lot easier to scale the app. I can just add another instance of push server or web server if necessary;
This is at least what I believe. The only problem is that when a client connects to the seperate socket.io server then it won't send cookies (different port, cross-domain policy).
The workaround I came up with is to put a reverse proxy (written in Node.js as well) in front and check what kind of request we are dealing with and send it to web server or push server accordingly. Great, now we have cookies in both web server and push server. The reverse proxy can be a load balancer which is an additional bonus.
It looks like a good idea to me. What do you think about this design? Perhaps any other workaround for cookie problem?
I recently did something simular, we initially used a node.js reverse proxy but ran into reliability/scalability problems. We found serving static files and proxying requests was best left to nginx. haproxy is also a very viable solution for stand alone proxying as well.
HaProxy
Nginix as a reverse proxy