fibonacci series azure serverless

'use strict';

function fib(maxLength=10, series=[1,1]) {
  const l = series.length;
  if (l >= maxLength) {
    return series;
  }
  series.push(series[l-2] + series[l-1]);
  return fib(maxLength, series);
}

module.exports.handler = async function(context, req) {
  const series = fib(req.query.length || (req.body && req.body.length))
  context.res = {
    body: series.join(','),
  };
};