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Fetch local files with Node.js

In a browser environment fetching a local file is quite trivial: one just need to start a server (using MAMP, XAMP, Mac's Python server, etc...), and then doing:
fetch("./foo.txt").then(etc...)
However, in Node.js this simple task has been a challenge. I've tried the same snippet using Node 18 (which comes with an experimental fetch API), but I'm always getting an invalid URL error:
TypeError: Failed to parse URL from foo.bar
[cause]: TypeError [ERR_INVALID_URL]: Invalid URL
I've tried installing node-fetch, but I'm getting the same error. I could start a local server for node like http-server, but it tells me to go to http://localhost:8080 to see the server, that is, using the browser, but the issue is that I can do that without node, using only a node build is the whole point.
My question is: is it possible to fetch a local file in a node build (Sublime Text, VS Code etc...), without using a browser? (note: I can do it with fs, but in my question I'd like to discuss fetch only)

My question is: is it possible to fetch a local file in a node build (Sublime Text, VS Code etc...), without using a browser? (note: I can do it with fs, but in my question I'd like to discuss fetch only)
The Node.js implementation of fetch does not currently support file: scheme URLs…
fetch("file:///tmp/123").then(r => r.text()).then(d => console.log(d));
reports:
Error: not implemented... yet...
…nor (it appears) does it resolve a relative path to a file: scheme URI.
You should use the fs module.

browserify Error : http.createServer is not a function

I tried to browserify this node js script :
var phantom = require('phantom')
phantom.create(function(ph) {
ph.createPage(function(page) {
page.open("editor.html", function(status) {
console.log("opened diagram? ", status);
page.evaluate(function() {
return document.getElementById("GraphImage").src;
}, function(result) {
//console.log(result);
ph.exit();
});
});
});
});
So I used this command:
browserify myscript.js > bundle.js
and when I run bundle.js from an html file I get this error:
http.createServer is not a function
it seems that browserify does not support httpserver. How can I resolve this problem?

You can't run a web server from inside a web browser. There really isn't anything in the browser that could act like Node's http module. Also it doesn't make sense to run PhantomJS in a browser, because PhantomJS is a web browser.
What is the desired behavior you are trying to accomplish?
Update:
It seems like you are trying to run code intended for Node.js inside a browser instead.
The JavaScript engine inside the browser is much more restrictive than in Node.js, for example you can't access the file system from inside the browser for security reasons (or else you could read the hard drive of anyone who visited your web page).
Browserify does include some "shims" that will put small JS libraries into your code that work in the browser and match the API of Node.js, allowing some Node.js specific JS code to execute in the browser.
In your case, you are requiring Phantom, which seems to in turn require http. Accoring to the Browserify documentation, it will see require('http') and include a shim for the http module (because browser's don't provide an http module of their own).
The Phantom module then tries to call http.createServer() but accoring to the documentation for that http shim:
This module implements http.request, http.get, and most of http.ClientRequest and http.IncomingMessage in addition to http.METHODS and http.STATUS_CODES.
so http.createServer() is not supported by the shim. This also makes sense because a browser would never let you open an http server inside of itself, or else navigation to someone's web site could cause your browser to start serving content to the outside world, which obviously doesn't make sense.
In your comment:
"i want that my node js script can be executed from another JS code"
You don't specify what "other JS code" is running in. If that JS code is already running in Node, then you don't need Browserify at all. If you are trying to have a web browser start up an actual Node.js process, that isn't going to happen, again for obvious security reasons, because browsing to a web page shouldn't have the ability to run any executable on your system.
What Browserify lets you do is take code originally intended for Node.js, and run it in a browser instead, but a t runtime it is executing in the browser, not in Node.js, so you can only use JS code that works within the constraints of the browser's JS runtime.
If you are trying to execute your code in Node.js, then you need to do that by having something start the Node.js executable, either from the command line or by having another program start the process for you, but that can't be done from within a web browser. If you are trying to have users navigate to your web site and then have this code run on their machines in a browser and not in Node.js, then you need to only use modules that work in the browser.

Deploying Node JS application over a server

I have done quite a research of deploying an application over the local server that I have on my machine. Each source code for the Node JS application or the example that is available over the internet specifies to run the application from the console.
Is there any way that i can configure my MAMP server so that when i hit a URL the Node code specified is executed.
Are there any parameters to set for the same ?
I looking forward to the steps to achieve this as i was not able to found a relevant answer for the same as such.

socket.io.js not loading

I know there are a bunch of questions on this already, but none have answered it for me, and plus mine is slightly different.
I'm starting the socket.io server in node using this:
var io = require('socket.io').listen(8000);
My terminal says everything is ok:
info - socket.io started
Now I am trying to load the .js file in my clientside browser using this url:
http://<hostname>:8000/socket.io/socket.io.js
I dont get a 404, it just hangs forever. I've also used a network utility to ping port 8000, and it seems to be open fine.
I installed node and socket.io just yesterday, so they should be the latest versions. Can anyone shed any light on this? Thanks!

Turns out the reason I could never request the .js file was because my company network blocks all ports except the usual ones (80, 21, etc), so `I would never be able to communicate with port 8000.

Use express.js. Place the socket.io file in public/javascripts folder and add this line to your html
<script src="/javascripts/socket.io.js"></script>
I think this is the best way. When you're writing http://<hostname>:8000/socket.io/socket.io.js
node tries to find a folder named socket.io in your project's public folder. And the file socket.io.js in it.
If you don't want to use express.js you should catch the request and try to load a file if no routes were found for your request (what actually express does) because node doesn't know what to do for requests which don't match any routes in your server.
And I recommend to use the socket.io.min.js file (it's smaller and it's in folder node_modules\socket.io\node_modules\socket.io-client\dist)

You have to start an http/https server to access it via http/https. Simply starting an socket.io server won't do. Do the following:
var http = require('http');
var app = http.createServer(),
io = require('socket.io').listen(app);
app.listen(7000, "0.0.0.0");
Then I can access the file http://localhost:7000/socket.io/socket.io.js
sockets.io uses websocket protocol (ws://). See the wikipedia page.

You need to get at least 3 pieces working together.
Serve some HTML (/index.html will do just fine) so there's a web page. This file should contain the socket.io client <script> tag. For this you need the http server portion of the starter examples. You are missing this and that's why browsing to your server just hangs.
Serve the socket.io client. Socket.io will do this for you automatically when you pass in your http server function to it. You don't need full express as this can be done with just node's http module as per the first example on the socket.io docs.
Some javascript to actually do something with the socket. This can be the content of a <script> tag in index.html or a separate file. If it's a separate file, you need to set up your http server to actually serve it.

Can Node.js be run within Tomcat server?

From what I have read so far in this blog http://nowjs.com/ I need to install nodejs in the server machine for it to work. But, I am using a shared server and don't really have any authority to put something into the server machine.
Putting it into the container(tomcat) is however another thing which I mostly do.
Generally speaking, when we say server we mean tomcat or websphere or jboss.
But with nodejs if I am not wrong server means the real machine on which tomcat etc. runs.
So is there any way I can run the nodejs server inside tomcat server or am I thinking about it the wrong way ?

Yes, you are thinking of it it the wrong way. The key feature of Nodejs is that it contains, amongst other things, a rather natty embedded HTTP server. Think Jetty. However it might be possible now or in the future to run JavaScript in tomcat.
I recommend going to http://nodejs.org/ and watching the video, it will surely clear the matter up for you.
Meanwhile I would recommend getting hosting which includes SSH access, and preferably root access. Root access will make installing node a whole load easier and allow you to run it on a commonly used port (avoid running node as root, use port mapping) . But you don't need a seperate web server to get started, you can install Node.js on windows, mac and linux.