This is a very rough beginning, one where I'm not even sure if I'm starting in the right place.
I have a "smart" AV Matrix switch from GoFanco. For anyone wondering, it is a device that allows multiple HDMI video signal inputs and then can output them to multiple outputs. You could use it to broadcast one HDMI signal to multiple outputs, switch the signal being broadcast, send them only to two outputs, etc. In short, it's a powerful HDMI switcher. This one is "smart" too, in that it has a cloud portal and can even be (clunkily) connected to an Alexa skill for control. Thankfully though, it also has local control, through a web interface of a local URL for the device, as seen in the image below:
I've looked all over and there isn't any documentation about an API for the device. The most I can find are some HEX codes that can be used when controlling the device through a serial cable. If it has a local, web-based UI, surely there's a way I can isolate commands the web UI kick off and have Hubitat "spoof" them, right?
Can anyone advise on how you would go about finding out what messages the web UI is sending to the device, and then maybe on how to have Hubitat send the same messages? Am I going about this the right way even?
Found what you likely found, and it's promising at least:
From the sound of the author's reason for writing this tool, the way the device uses HTTP POST is a mess, so he created this service. It was easy to configure and run, and after setting that up, visiting the local URL of the service and clicking various links does control the device. For example, I can visit loadmap?map=1 and it applies my AV mapping set up in mapping 1. I do wish there was a simple way to go directly to what this service app is doing, but I can't find it.
At a simpler level, how would I use Hubitat to trigger the service? For example, I have a rule machine rule set up to trigger off a virtual button. I assume the action needs to do one of these:
However, which would it be and how should the message/URL be formatted if I wanted Hubitat to simulate my clicking that URL to load mapping 1? Sorry, I know this is a complete beginner type of question, and I'm likely even missing some nuances on what I'm asking.
I assume the "Send HTTP Post" option, with the properly-formatted request would be used to cut this middle man service out to accomplish the same thing, but I again am not sure how to read what the service is actually sending to my device.