blabla.js

async function getNodes() {
  return new Promise((resolve, reject) => {
    
  http.get('http://localhost:3000', (res) => {

    const statusCode  = res.statusCode;
    const contentType = res.headers['content-type'];

    res.setEncoding('utf8');
    let rawData = '';

    res.on('data', (chunk) => rawData += chunk);
    res.on('end', () => {
      try {

        let parsedData = JSON.parse(rawData);

        parsedData.forEach( function (data, idx) {
          nodes[0][idx].label = data.label;
        });
        resolve(nodes);
      } catch (e) {
        console.log(e.message);
      }
    });
  }).on('error', (e) => {
    console.log(`Got error: ${e.message}`);
  });
  });

};
async function main() {
  var nodes = await getNodes();
  // use nodes here
};