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http-proxy-middleware econnreset error after successful post request

Developing a contact form using Nodejs/Express and create-react-app following this tutorial https://www.youtube.com/watch?v=o3eR0X91Ogs. The issue that I'm running into is that when I hit submit on the form the message succeeds, and I get it in my inbox. However, in the developer console, I am hit with the timeout error I set on the axios.post located in Contact.js, and in my terminal it logs message sent, console log located in index.js, immediately throwing the following error afterward:
HPM ERROR: Error: socket hang up
[1] at connResetException (internal/errors.js:612:14)
[1] at Socket.socketCloseListener (_http_client.js:443:25)
[1] at Socket.emit (events.js:326:22)
[1] at TCP.<anonymous> (net.js:673:12) {
[1] code: 'ECONNRESET'
[1] }
[1] [HPM] Error occurred while trying to proxy request /api/contact/ from localhost:3001 to http://localhost:3000/ (ECONNRESET) (https://nodejs.org/api/errors.html#errors_common_system_errors)
Does anyone know why this error is occurring, and how I can fix it? The message sends but hangs afterward which prevents the app state from resetting (resetForm). At the same time, the axios.post in Contact.js doesn't update the state of sent to true.
The Github repo for the project.
Edit: I've been stuck on this for a few days now. Looked at similar questions, attempted ALL the fixes I could find, and this error still persists.

This is a common misunderstanding about how ExpressJs responses work. If you don't send a response to the request, it'll be stuck forever. So all you have to do is to send a response! Also, the res variable was re-defined in the callback of sendMail function. Here is the fix:
app.post('/api/contact', (req, res) => {
// ...
smtpTransport.sendMail(mailOptions, (err, mailResponse) => {
if(err) {
console.log(err);
} else {
console.log('Message sent!');
}
smtpTransport.close();
return res.send(err ? err : 'Message sent!');
});

npm mqtt module just keeps running without doing anything?

I´m pretty new in the whole JS and node.js and npm thing and im trying to use a mqtt broker in a project I have for a class, so I installed the mqtt module from npm and to give me an idea of how it works I ran the example in the npm page but it doesn´t seem to work, it just hangs without ever printing the "hello mqtt" it says it should? im sure im missing something but i really don´t know what.
The code is:
var mqtt = require('mqtt')
var client = mqtt.connect('mqtt://test.mosquitto.org')
client.on('connect', function () {
client.subscribe('presence')
client.publish('presence', 'Hello mqtt')
})
client.on('message', function (topic, message) {
// message is Buffer
console.log(message.toString())
client.end()
})
the page I got it from is https://www.npmjs.com/package/mqtt
i also tried using my own broker but it also doesnt work.

This could be so many things, but the most likely is that you are failing to connect to the broker.
The sample code has no error handling at all so it's not going to tell you when it fails to connect. Try the following code which should tell you what's going on.
var mqtt = require('mqtt')
var options = {
connectTimeout: 10000
};
var client = mqtt.connect('mqtt://test.mosquitto.org',options)
client.on('connect', function () {
console.log("connected");
client.subscribe('presence')
client.publish('presence', 'Hello mqtt')
})
client.on('error', function(err){
console.log("error %j", err);
});
client.on('close',function(){
console.log("client disconnected");
});
client.on('message', function (topic, message) {
// message is Buffer
console.log(message.toString())
client.end()
})
I've wound the connection timeout down to 10 seconds from the default 30 so you can see it fail quicker.

Why am i getting this error running 'net' module node.js

I am using .net modular and opening tcp port on 6112.
var net = require('net');
var server = net.createServer(function (socket) { //'connection' listener
});
server.listen(6112, function () { //'listening' listener
console.log('server started');
});
On the same machine i start a java socket in main.
public static void main(String[] args) {
// TODO Auto-generated method stub
try {
System.out.println("Connecting...");
Socket socket = new Socket("localhost", 6112);
System.out.println("Connected");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
I get this exception,
C:\Users\Mustafa\WebstormProjects\Node.Js>node hello.js
server started
events.js:72
throw er; // Unhandled 'error' event
^
Error: read ECONNRESET
at errnoException (net.js:884:11)
at TCP.onread (net.js:539:19)
Is this like a bug or something, cause if once i get through this bug, I will be good thanks.
I haven't used the debugger cause as Ryan said it him self a year ago that it is still shitt.

You need to listen for errors on the socket. Node has the default behavior that when something does .emit('error'), if there are no error handlers attached, it will throw the error instead, thus crashing the application.
var server = net.createServer(function (socket) {
socket.on('error', function(err){
// Handle the connection error.
});
});

You are creating a socket and connecting from it, but not closing it. So when the program finishes, to node.js it looks like connection is reset (closed abruptly). Call socket.close(); before program finishes.
You can structure your code in this way :
try {
tryStatements //your code that is causing exceptions
}
catch(exception){
catchStatements //handle caught exceptions
}
finally {
finallyStatements //execute it anyways
}
Or if you like to catch uncaught exceptions from runtime, use this (main process won't exit on exceptions)
process.on('uncaughtException', function(err) {
console.log('Caught exception: ' + err);
console.log(err.stack);
});
The problem is in java code which is causing node.js to exit on exception. So be sure to add socket.close();. Above is just error handling on node.js part.

Catch exception in node.js

I have a simple program, which needs to make sure I can connect to a Redis server. I use node-redis to connect and need to wait until Redis is started. I use this piece of code:
function initializeRedis(callback) {
(function createClient(){
var runner;
try {
client = redis.createClient();
} catch (e) {
setTimeout(createClient, 1000);
}
callback();
})();
};
initializeRedis(function() {
// Work here
});
This is because without the try/catch, I got an exception from node.js:
node.js:134
throw e; // process.nextTick error, or 'error' event on first tick
^ Error: Redis connection to 127.0.0.1:6379 failed - ECONNREFUSED, Connection refused
at Socket.<anonymous> (/var/www/php-jobs/node_modules/redis/index.js:88:28)
at Socket.emit (events.js:64:17)
at Array.<anonymous> (net.js:830:27)
at EventEmitter._tickCallback (node.js:126:26)
When I start redis-server (Ubuntu machine) and start this script, everything works fine. If I stop redis-server and start the script, it doesn't catch the exception and still throws this same exception. How is that possible? I have a try/catch statement!

After client = redis.createClient();, set a handler for the error event:
client.on('error', function(err) {
// handle async errors here
});
Have a look at the stack trace - your code isn't in it, so there's no place where a try/catch could catch the error.

How do I fix this error with node.js and node-imagemagick: Error: Command failed: execvp(): Permission denied?

Im getting this error:
Error: Command failed: execvp(): Permission denied
When I do a simple node-imagemagick script:
im = require('imagemagick');
im.identify.path = '/tmp/node_thumbs/';
im.identify('cool.jpg',function(err,features){
if(err) throw err;
console.log(features);
});
Any ideas on what could be causing this?

The permission denied is from trying to launch the ImageMagick command, not in the process of executing it.
If you look at the documentation, identify.path is "Path to the identify program." In this case, you're redefining the path to the executable as /tmp/node_thumbs/, which presumably is not the executable.
You probably simply want:
var im = require("imagemagick");
im.identify('/tmp/node_thumbs/cool.jpg',function...