This is a very simple docker image with pm2, the process manager installed.
The image will use /app folder as the place for the source code and the working directory, so you should provide your app as a volume, i.e;
-v /path/to/app/source:/app
Also, the executable (app entry js file) should be noted as the environment variable APP. The default value for APP variable is app.js.
The container exposes 80 and 443 ports so you can bind to them.
So a complete command for running a node.js application with pm2 would be;
docker run -d -e "APP=app.js" -p 3000:80 -v /path/to/app/source:/app dashersw/node-pm2