nut-client

nut-client

Description

nut-client is a Node.js client for Network UPS Tools (NUT), enabling advanced communication with NUT servers for UPS management. It is built to be robust, performant, and easy to integrate, supporting parallel requests and event-based monitoring via Promises.

Installation

npm install nut-client

Features

• NUT Command Support : Most NUT commands are supported, with automatic parsing of responses to simplify integration. Additionally, a manual mode is available for full control.

  import { NUTClient } from 'nut-client'
  
  const client = new NUTClient('127.0.0.1', 3493);
  
  console.log(client.listUps());
  console.log(client.listVariables('ups'));
  
  //manual command
  console.log(client.send(['LOGIN', "myups"]))
  

• Parallel Request Handling : Unlike other NUT libraries, nut-client manages an internal queue to handle parallel requests without conflicts, using Promises for efficient request handling.

  import { NUTClient } from 'nut-client'
  
  const client = new NUTClient('127.0.0.1', 3493);
  
  const [ups1, ups2, ups3] = await Promise.all([
    client.getUPS('ups1'),
    client.getUPS('ups2'),
    client.getUPS('ups3'),
  ])
  
  

• StartTLS Support : Communicate securely with the NUT server using StartTLS for encryption.

  
  import { NUTClient } from 'nut-client'
  
  const client = new NUTClient('127.0.0.1', 3493);
  
  //use clear tcp connection
  console.log(await client.version());
  
  await client.startTLS({
    // allow self signed certificate
    rejectUnauthorized: false
  });
  
  //use encrypted tcp connection
  console.log(await client.version());
  

• Built-in Monitor : A Monitor module reads variables at regular intervals, emitting UPS events similar to upsmon (plus some additional ones).

  const client = new NUTClient('127.0.0.1', 3493);
  const monitor = new Monitor(client, 'myUps');
  
  //use events like UPSMON
  monitor.on('ONBATT', () => {
    console.log('UPS "myUps" lost power and is now on battery');
  });
  
  // listen on specific variable changed
  monitor.on('VARIABLE_CHANGED', (key: string, oldValue: number, newValue: number) => {
    if(key !== "battery.charge" || isNaN(oldValue) || isNaN(newValue)) {
      return;
    }
  
    console.log(`battery is ${oldValue > newValue ? 'dis':''}charging`)
  })
  
  // listen on all events
  monitor.on('*', (event: string, ...args) => {
    console.log(`receive event ${event} with args`, args);
  })
  
  // other events available in the technical documentation
  // https://thib3113.github.io/nut/interfaces/IMonitorEvents.html
  
  await monitor.start();
  

• Fully Typed with TypeScript (ESM + CJS) : Built with TypeScript, nut-client is distributed in both ESM and CommonJS modules for maximum compatibility.

Contributing

Contributions are welcome! If you have suggestions, feel free to open an issue or a pull request.