Lxd api example: lxc exec and operations websocket via nodejs

events-websock.js

const fs = require('fs')
const WebSocket = require('ws');

const wsoptions = {
  cert: fs.readFileSync('../../.config/lxc/client.crt'),
  key: fs.readFileSync('../../.config/lxc/client.key'),
  rejectUnauthorized: false
}
   
var ws = new WebSocket('wss://127.0.0.1:8443/1.0/events?type=operation', wsoptions);
    
ws.on('open', function open() {
  console.log('open for notifications')
});

ws.on('error', (error) => {
  console.log(error)
});

ws.on('message', function(data, flags) {
  var buf = Buffer.from(data)
  console.log(JSON.stringify(JSON.parse(data.toString()), null, 4))
});

lxd-exec-websock.js

const https = require('https');
const fs = require('fs');
const WebSocket = require('ws');

const options = {
    method: 'POST',
    host: '127.0.0.1',
    port: 8443,
    path: '/1.0/containers/lxd-websock/exec',
    cert: fs.readFileSync('../../.config/lxc/client.crt'),
    key: fs.readFileSync('../../.config/lxc/client.key'),
    rejectUnauthorized: false
}

const body = JSON.stringify({
  "command":["/bin/bash"],
  "environment":{"MY_KEY":"my_value"},
  "interactive":true,
  "wait-for-websocket":true
})

const req = https.request(options, res => {
  res.on('data', d => {
    const output = JSON.parse(d);
    
    const wsoptions = {
      cert: options.cert,
      key: options.key,
      rejectUnauthorized: false 
    }

    const ws = new WebSocket('wss://' +
      options.host + ':' + options.port + output.operation +
      '/websocket?secret=' + output.metadata.metadata.fds['0'],
      wsoptions
    );
        
    ws.on('open', () => {
      console.log('connection opened');
      ws.send('printenv \r', { binary: true }, () => {
        setTimeout(() => ws.send('exit \r', { binary: true }), 100);
        setTimeout(() => process.exit(0), 200);
      });
    });

    ws.on('error', error => console.log(error));

    ws.on('message', data => {
      const buf = Buffer.from(data);
      console.log(buf.toString());
    });
  });
});
req.write(body);
req.end();

req.on('error', (e) => {
  console.error(e);
});

Thanks for this,

If you're connecting to local LXD with node, you don't need to setup certificates if you use.

require('child_process').exec

and use it to call this little gem:

lxc query -X POST -d '{"command":["/bin/bash"],"environment":{"MY_KEY":"my_value"},"interactive":true,"wait-for-websocket":true}' /1.0/containers/c1/exec

That will the give you the operation id and the secret which is required for the websocket.

Your the best for this ❤️ I wasted some much time and went through so many web socket libraries ❤️

Hello guys
I want to connect my container LXD to xterm.js for a terminal bash on my website
my IP server LXD is 192.168.1.207:8443
my certificates path /var/www/html/plateforme/client.crt and client.key