Development Tools

PM2 comes with two development tools that will help you on the development stage: a watch and restart mode and a server for static files.

Watch and Restart

The watch and restart mode watches the current directory to detect file changes and auto-start.

This mode can be enable in your ecosystem.config.js:

module.exports = {
  apps : [{
    name: "app",
    script: "./app.js",
    watch: true,
  }]
}

Beware that the watch and restart mode makes hard restart, without sending SIGINT.

Watch options

You can use advanced options to specify path to watch or path to ignore.

module.exports = {
  apps : [{
    name: "app",
    script: "./app.js",
    watch: ".",
  }]
}

• watch can also be a string or an array of paths to watch. Current directory is watched when set to true.
• ignore_watch can be an array of paths or a string. It is used by the chokidar dependency as a glob or a regular expression.
• watch_options is an object that is given as options to chokidar dependency (default options used by pm2 are persistent and ignoreInitial set to true)

When working with NFS devices you’ll need to set usePolling: true as stated in this chokidar issue.

With CLI

Watch mode can also be enabled via CLI with

pm2 start app.js --watch

However, please note that when --watch is enabled, you must use pm2 stop --watch <app_name> to stop the process, as simple stop won’t stop the watching.

Serve static file over HTTP

pm2 can serve static files (like a frontend app) over HTTP with:

pm2 serve <path> <port>

As default values are current folder and 8080, you can then just use:

pm2 serve

In the ecosystem file:

module.exports = {
  apps: [{
    name: "static-file",
    script: "serve",
    env: {
      PM2_SERVE_PATH: ".",
      PM2_SERVE_PORT: 8080,
    },
  }]
}

and start with:

pm2 start ecosystem.config.js

All other pm2 options are still available.

Next Steps

Easy Deploy with SSH