import { buildClient } from '@datocms/cma-client-node';
async function run() {
  const client = buildClient({ apiToken: '<YOUR_API_TOKEN>' });
  
  const environmentId = 'main';
  
  const environment = await client.environments.fork(environmentId, {
    id: 'my-sandbox-env'
  }, {
    immediate_return: true,
    fast: true,
    force: true
  });
  
  console.log(environment);
}
run();

{
  id: 'main',
  meta: {
    status: 'ready',
    fork_completion_percentage: 95,
    read_only_mode: true,
    created_at: '2020-04-21T07:57:11.124Z',
    last_data_change_at: '2020-04-21T07:57:11.124Z',
    primary: true,
    forked_from: 'main'
  }
}