Define PM2 script path with environment variable

I'm building a simple staging CI environment where I define the path of the runnable Node application by an environment variable APP_PATH.

Is it possible to tell PM2 in a process config file to look up the startup script by following the path in the APP_PATH variable?

Like this:

{
  "apps": [
    {
      "name": "my_app",
      "script": "$APP_PATH/app.js"
    }
  ]
}

Currently, I get a [PM2][ERROR] script not found : message from PM2 when starting the above configuration.

via m3dw3