SOURCE

console.log('order_number', createOrderNumber(10))
function createOrderNumber(count){
  var arr = ['0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z']
  let str = ''
  for(let i = 0; i < count; i++){
    let numstr = arr[Math.floor(Math.random()*arr.length)]
    if(i == 0 && numstr == '0'){
      console.log('numstr')
      return createOrderNumber(count)
    }
    str += numstr
  }
  return str.toUpperCase()
}