If you are trying to use that package you will need to create a custom docker image that includes it and make sure you have the env options set to allow it to be used, There are examples on the forum on how you can do this if needed.
That is just a docker run command rather than something that you would make a docker file, Luckily though as long as you continue to use -v n8n_data:/home/node/.n8n your data will be safe.
But you will also need to set the env option NODE_FUNCTION_ALLOW_EXTERNAL to include the package you want to use or it still won’t work. Please don’t forget that this is considered an advanced feature so on top of the usual skill set required to run n8n you are also now making your own custom docker images so you will need to be comfortable with the different options around that as well.
The config looks ok to me for nginx but I am not an expert when it comes to nginx, The issue could also be with your code, Typically the code node is not used for running things that may require interaction so if you are expecting Mattermost to call back it may never happen.
So there is some solution to do websocket exchange with n8n ?
I tried with postman, is a success
I tried with a javascrit script, it’s ok too
So I would like to integrate this in N8n to make my bot Mattermost, miss only 1 thing : N8n