Best practice to Upload file to the Server using AngularJS and NodeJS

   var uploadUserFile = function(file) {
      var uploadFileUrl = "/api/v1/upload/;
      var uploadFile = Upload.upload({
         url: uploadFileUrl,
         file: file
      });
  }       

router.post('/api/v1/upload/', FileUploadController.saveFile);

var UploadService = require("uploadService").UploadService; 
module.exports.CompanyPoliciesController = (function() {
    var saveFile = function(req, res) {
        UploadService.saveFile(req.files.file, res);
    }
    return {
        saveFile: saveFile
    };
})();

module.exports.UploadService = (function() {
    var uploadCompanyPolicyFileToServer = function(file, res) {
        var fs = require('fs');
        var path = require('path'); // to create a path seperator
        var mkdirp = require('mkdirp'); // to create directory
        var uuid = require('node-uuid');
        var filePath = '/opt/userFiles/';

        mkdirp(filePath, function (err) {
            if (err) {
                configurationHolder.ResponseUtil.responseHandler(res, err, err.message, true, 400);
            } else {
                var target_path = filePath + file.originalFilename,
                tmp_path = file.path;
                var source = fs.createReadStream(tmp_path);
                var dest = fs.createWriteStream(target_path);
                source.pipe(dest);
                source.on('end', function(err) {
                    if (err) {
                        configurationHolder.ResponseUtil.responseHandler(res, err, "failed to upload " + file.name, true, 400);
                    } else {
                        configurationHolder.ResponseUtil.responseHandler(res, {}, File upload successfully, true, 400);
                    }
                });
            }   
        });
    }
    return {
        saveFile: saveFile
    }
})();