file-scan-api.js

const nvt = require('node-virustotal'); // read more https://www.npmjs.com/package/node-virustotal
const fs = require('fs');
const crypto = require("crypto");

app.post('/upload', async (req, res) => {
  const randomId = crypto.randomBytes(16).toString("hex");
  const filePath = __dirname + "/uploads/" + randomId;
  const writeStream = fs.createWriteStream(filePath);
  writeStream.on('finish', () => {
      try {
        await scanFile(filePath, randomId, "");
        // upload to SW
      } catch  {
         // malware detected
      }
  })
  request.pipe(writeStream);
});


function scanFile(filePath, fileName, mimeType) {
  return new Promise((resolve, reject) => {
      const defaultTimedInstance = nvt.makeAPI();
      const aMaliciousFile = fs.readFileSync(filePath);
      const theSameObject = defaultTimedInstance.uploadFile(aMaliciousFile, fileName, mimeType, function(err, res){
        if (err) reject(err);
        else resolve(res);
      });
  })
}