WARNING!

# -*- coding: utf-8 -*-

import os
import sys
from pprint import pprint


import ccxt  # noqa: E402


# WARNING!
# This example measures the round-trip time by fetching the orderbook from an exchange
# In order to measure the speed of requests it disables the rate-limiting
# Disabling the rate-limiter is required to do an accurate measurement
# If you keep running without a rate limiter for a long time the exchange will ban you
# In a live production system always use either the built-in rate limiter or make your own


def main():

   # the exchange instance has to be reused
   # do not recreate the exchange before each call!

   exchange = ccxt.binance({

       # if you do not rate-limit your requests the exchange can ban you!
       'enableRateLimit': False,  # https://github.com/ccxt/ccxt/wiki/Manual#rate-limit

   })

   exchange.load_markets()  # https://github.com/ccxt/ccxt/wiki/Manual#loading-markets

   # exchange.verbose = True  # uncomment for debugging purposes if needed

   symbol = 'BTC/USDT'

   results = []
   num_iterations = 50

   for i in range(0, num_iterations):
       started = exchange.milliseconds()
       orderbook = exchange.fetch_order_book(symbol)
       ended = exchange.milliseconds()
       elapsed = ended - started
       print(elapsed, 'ms')
       results.append(elapsed)

   pprint(results)

   rtt = int(sum(results) / len(results))
   print('Successfully tested', num_iterations, 'calls, the average round-trip time per call is', rtt, 'milliseconds')


main()