socket-io | A Socket.IO client for C | Socket library

I'm learning socket.io and typescript. I'm currently building an app where I want to emit event on databases changes to the client.For the backend, I'm using Express, typescript and nodeJS

I've looked on a lot of posts but I don't understand how I can access my io instance to be able to emit my event from my controller functions. Also most examples are on javascript which is more confusing.

Currently in my app.ts I have the following configuration. How can I move my addOnlineHandler, logOutHandler and sendNotificationHandler in my controller functions to be able to emit event on database change directly from createOrder function of the controller ?

I've tried importing all orderHandler function in the controller but it's not working. I'm unable to access the io instance to emit events.

I'm trying to convert an angular project to ionic, i've initialised and changed the config in angular.json, package.json and ionic.config.json project name matches.

The project name is simply "frontend", but when i now try to use ionic serve i'm getting this:

An unhandled exception occurred: Project does not exist.

I've checked everything i can think of and i don't see why it's not picking the project up, could do with a fresh pair of eyes please. I have listed each config file below, and i can't see any issue!

package.json:

I have a pre-developed angular project, i just ran npm i to install its packages locally, then ng serve to run the project, the project works well without problems but..

when i wanted to create a new component with ng g c new-component i got this error:

The idea is that the sensor in water will send data to my database, and I want the data to be sent to the frontend in real-time, in other words: Database update and then frontend update.

The tools I use:

1. MongoDB
2. NodeJS
3. Socket io
4. ReactJS

It works fine actually and here is my main code to handle real-time data flow

Complete noob here learning c++ through an IoT project using Websocket. So far, somewhat successfully modified this example beast async_client_ssl to handshake with a server.

My problem is ioc.run() runs out of work and exits after the initial callback. I was having the same issue as this post two years ago. Boost.best websocket ios.run() exits after sending a request and receiving one reply

The answers from the linked post above were pretty simple (1. and 2.), but I still have no clue how to implement it.

1. Without reading your code, understand that the run() method terminates if there is no pending work. For instance, your read method needs to queue up a new read.

2. Move async_read() to a separate function, let’s say do_read(), and call it at the end of on_read()as well as where it currently is.

The person who asked the question in the post also seemed puzzled, but after these two answers, there was no further explanation. So, is there anyone who can kindly help me out, perhaps with a simple code snippet?

In on_read() in the code from some other noob's previous post, I added the async_read() like below.

I'm trying to use namespaces with a socket-io server and a react client.

Client

I have a HTTP nodejs/socketio server running on port 3001 successfully. I'm trying to access the server from a SSL website encrypted with certbot (let's encrypt).

When I visit https//:example.com/index.html, I see 404 error :

GET https://www.example.com:8000/socket.io/socket.io.js net::ERR_ABORTED 404 (Not Found)

I've been reading about configuring apache with mod_proxy here and here. HOWEVER, according to nodejs documentation, all is needed is pem files which I have.

I feel like I'm chasing my own tail and I need help. I've been spending nearly a week doing research and trying different approaches. I'm back at square one. Anyone ran a https server and accessed it over SSL website successfully? Here all the relevant codes below.

server.js

I'm trying to use the express-session library in my MERN stack app along with socket.io for the real time messaging part of the app.

For authentication I am using express-session and would like to use that same middleware for socket connections, however when I followed the answer for the same problem here, the middlware just simply didn't proceed to the next function and so when trying to connect, the middlware never went to the onConnect handler and the handshake never completed.

This is the extension of my last question here:

socket.io always has connection false

For now, I have two servers deployed in two different domain names. The first server works perfectly fine with socket.io, so I redeployed the server to the new domain name by simply pull the same branch from GitHub, install everything and run it. And then I found that all my socket.io connections failed and the symptom is exactly the same as last time: connection always 'false' and disconnection always 'true'.

This time I am pretty sure it is not related with cors, because I tried io.origins((origin, cb) => if (whitelist.includes(origin)) { cb(null, true) } else { cb('failed', false) ) and it shows the origin is allowed.

I also tried cors: { origin: '*' } and that also doesn't work.

Strangely, despite the fact that they are using the same code, connecting to the first domain name works perfectly fine. But the second one has the issue.

UPDATE:

I use this to track the error message.