wsServer | wsServer - a tiny WebSocket server library written in C | Websocket library

This is a problem I once had when attempting to send numpy images (converted to bytes) through sockets. The problem was that the bytes string was too long.

So instead of sending the entire image at once, I sliced the image so that I had to send, say, 10 slices of the image. Once the other end receives the 10 slices, simply stack them together.

Keep in mind that depending on the size of your images, you may need to slice them more or less to achieve the optimal results (efficiency, no errors).

The problem was not specifying the protocol when accepting the connection. After about 20 hours working on the same bug and implementing an SSL certificate to get it to work, I changed:

In answer to "How to Send and/or Stream array data that is being continually updated to a client" as arrived at in comment.

A possible solution using WebSockets may be to

1. Create an interface on the server for array updates (if you haven't already) that isolates the array object from arbitrary outside modification and supports a callback when updates are made.

2. Determine the latency allowed for multiple updates to occur without being pushed. The latency should allow reasonable time for previous network traffic to complete without overloading bandwidth unnecessarily.

3. When an array update occurs, start a timer if not already running for the latency period .

4. On timer expiry JSON.stringify the array (to take a snapshot), clear the timer running status, and message the client with the JSON text.

A slightly more complicated method to avoid delaying all push operations would be to immediately push single updates unless they occur within a guard period after the most recent push operation. A timer could then push modifications made during the guard period at the end of the guard period.

The WebSockets API does not directly support broadcasting the same data to multiple clients. Refer to Server Broadcast in ws documentation for an example of sending data to all connected clients using a forEach loop.

Client side listener

In the client-side message listener

You are surely trying to connect to the wrong destination. It says wss:///ssa/wss/, but probably it should be wss://your.site.domain/ssa/wss/ .

So let's look at front end code and find out what's wrong with it.

This if(msg.operation="add_stat"){ will always push something on the stack.

Change to if(msg.operation==="add_stat"){

It is strongly discouraged from using PHP with Symfony and/or Doctrine for any long-running background processes (daemon), that listens for WebSocket (or other) connections, using Ratchet/ReactPHP style features in any production/real-world environments. PHP was not designed to run as a daemon. As such, without proper planning, the process will crash with either a Doctrine Connection exception with the MySQL Server Has Gone Away error or from memory leaks caused by maintaining the Entity Manager, Symfony service definitions and logger overflows.

Using PHP as a daemon would require implementing unintuitive workarounds, such as a Messenger Queue (causes long delays between responses) or Lazy Proxy objects (causes code-level maintainability issues) and additional background processes, like supervisor and/or cron jobs to circumvent the inherent issues and recover from crashes.

See below for a NodeJS alternative solution, to avoid the PHP daemon issues.

Provided you are using the default autowire configuration for your config/services.yaml and ScoreHandler is not in one of the excluded paths, the following options are feasible using dependency injection.

A few ideas:

1. Export the wsServer object so anyone importing your module can get access to it to install their own listeners on it such as their own connection listener.

2. Export a function/API that other modules can call to say what listeners they want on any incoming socket. You would have to store those listeners and then when you got a new incoming connection, you would install the stored listeners on that socket.

3. Export a function/API that gets the current wsServer object so anyone can install their own listeners on it such as their own connection listener. This is conceptually similar to option #1, but allows for the timing of the wsServer object to be more dynamic and may work better with the more static ESM exports.

The error I think is caused by having two :: in this line. Please use the following line which has only one.

Problem solved.

It was a load balancer issue. Apparently this doesn't work well with Classic Load Balancer. I believe it's due to the way it's requested.

Changing over to a Application Load balancer fixed the issue for me.