How to communicate between a UXP plug-in and a Python module?

Hi there! I am looking for the best strategy to create a channel of communication between a Photoshop UXP plug-in and a Python module. They will be both be running on the same machine. The plug-in needs to send some data to the Python module, the Python module will modify it slightly and send it back.

I would have done this using “child process”, but it has become clear that UXP does not support that functionality yet. What would be the best alternative?


You can use WebSockets for this functionality.

Python would be your web socket server (this is the first link that Google gives me – so no promises on library quality: websockets 10.2 documentation), and then the UXP plugin would establish a connection as a client. Once a connection is established, communication is bi-directional.

The hardest part is establishing the server and communicating the port # to use. Right now you have to rely on the Python side to be running, and once running to write a port # into the plugin’s data folder so that the plugin can pck that port # up and use it. (Or you can use a fixed port # – up to you.)

In the future, if your python side was registered with a URI scheme, UXP could launch it automatically if it wasn’t already running. (This will be in UXP 6.0. If you aren’t in the Ps prerelease - you should join – reach out to @Erin_Finnegan if you need assistance.)


Hi Kerri!

Are there any examples available of how to get a plugin to pick up a (fixed) port number?

I’m working on integrating PS into our facility’s pipeline and the majority of our tooling is Python based so this would be extremely helpful!

Many thanks,

I just realised I’m apparently blind and missed the very obvious example here! :man_facepalming:t3: