Has anyone written a program that can connect to JSON and create a virtual port that any application can access? For example Universal Gcode sender. I’ve had a look around but can’t see anything.
No one has really done this, but there is a way to do it without one such tool. If you are on a Unix or Unix-like machine (*Linux, *BSD, macOS…), you can use the command-line utility netcat to connect. SPJS uses WebSockets to perform its communications, so everything is conveniently sent in plaintext, meaning you can copy-paste the JSON into the prompt. I’m not sure if this would help you, but it is at least marginally in the right direction.