Promise to write data into a CSV file using npm module 'csv-write-stream'

promiseWriteCsvFile.js

    putPortfolioData = function(result, dataSinkName) {
      return new Promise(function (resolve, reject) {
        var filename = __dirname + dataSinkName,
        writer = csvStream(),
        ws = fs.createWriteStream(filename)
        ;

        writer.on('error', function(error) {
          reject(error);
        });
        writer.on('end', function() {
          resolve(result);
        })

        writer.pipe(ws);
        result.forEach(function(obj) {
          writer.write(obj);
        });
        writer.end();
      });
    };

This code works flawlessly when running tests with Mocha. When it is invoked by the real nodejs app, the CSV file is created, but it is empty and no warning/error whatsoever is thrown. Pls see this question on SO

I am working on Windows 7. Node 6.9.4, Npm 3.5.3, csv-write-stream 2.0.0.

Solved my issue by resolving the promise inside ws.on('finish', callback). See here.