Enable X-Frame-Options on express.js

frameguard-allow-X-Frame-Options

const frameguard = require('frameguard')

// Don't allow me to be in ANY frames:
app.use(frameguard({ action: 'deny' }))

// Only let me be framed by people of the same origin:
app.use(frameguard({ action: 'sameorigin' }))
app.use(frameguard())  // defaults to sameorigin

// Allow from a specific host:
app.use(frameguard({
  action: 'allow-from',
  domain: 'http://example.com'
}))