pm2 example

pms-development.sh

#!/usr/bin/env bash

#install pm2
npm i pm2

#run with process.json configuration file for development environment 
pm2 start process.json --env development

# delete it all
# pm2 delete process.json

process.json

{ // very good docs at http://pm2.keymetrics.io/docs/usage/application-declaration/#attributes-available
  "apps": [
    {
      "name": "my application",
      "instances": 0, // 0 means create instances to number of CPU cores on host
      "script": "app.js",
      "watch": true,
      "ignore_watch": [
        "/[\s\S].spec.js$/", // don't restart on test file change
        "node_modules",
        "docs"
      ],
      "exec_mode": "cluster", // or fork
      "interpreter_args": "--harmony",
      "error_file": "/var/tmp/my_application/error.log", // it will be created if nonexistent
      "min_uptime": 500,
      "max_restarts": 10,
      "restart_delay": 1000,
      "env_development": {
        "NODE_ENV": "development",
        "API_KEY": "albnxmzndf8"
      },
      "env_production": {
        "NODE_ENV": "production",
        "API_KEY": "praXnafinDef!1"
      }
    }
  ]
}