ESun Bank Forex Historical Data Crawler as a Python script

fetchCurrencyData.py

#!/usr/bin/env python

##############################################################################
# fetchCurrencyData.py                                                       #
#                                                                            #
# Requirements                                                               #
#                                                                            #
# - Python 3                                                                 #
# - Selenium package for Python                                              #
# - The web driver for Chrome                                                #
#                                                                            #
# 2018, Michael Chen; Apache 2.0                                             #                    
##############################################################################

import csv
import os
import sys
import time

from selenium import webdriver


currency = None
downloadPath = os.path.dirname(os.path.abspath(__file__))

if len(sys.argv) < 2:
    sys.stderr.write("No valid currency\n")
    sys.exit(1)

currency = sys.argv[1]

# Create a new instance of the Chrome driver
driver = webdriver.Chrome()

# Go to ESun Bank Historical Data page
driver.get("https://www.esunbank.com.tw/bank/personal/deposit/rate/forex/exchange-rate-chart")

# Wait the page to fresh.
time.sleep(10)

# Select currency menu.
currencyArrow = driver.find_element_by_css_selector(".transformSelect li span")
currencyArrow.click()

# Select currency.
currencyOptions = driver.find_elements_by_css_selector(".transformSelectDropdown li span")
for c in currencyOptions:
    if currency in c.text:
        c.click()
        break

# Wait the page to fresh.
time.sleep(3)

spotBtn = driver.find_element_by_css_selector(".radioBtns [for=\"spot\"]")
spotBtn.click()

# Wait the page to fresh.
time.sleep(3)

# Select duration.
durationBtn = driver.find_element_by_css_selector("div [for=\"oneYear\"]")
durationBtn.click()

# Wait the page to fresh.
time.sleep(3)

# Select data type.
dataBtn = driver.find_element_by_css_selector(".radioBtns [for=\"data\"]")
dataBtn.click()

# Wait the page to fresh.
time.sleep(3)

sys.stderr.write("Write data to csv file...\n")

with open("%sto%s.csv" % (currency, "TWD"), 'w', newline='') as csvfile:
    csvwriter = csv.writer(csvfile)

    csvwriter.writerow(["Date", "SellingRate", "BuyingRate"])

    hasMorePages = True

    while hasMorePages:
        items = driver.find_elements_by_css_selector("#inteTable tbody tr")

        for item in items:
            tds = item.find_elements_by_css_selector("td")

            if tds[0].get_attribute("class") != "itemTtitle":
                continue
            
            csvwriter.writerow([tds[0].text, tds[1].text, tds[2].text])
        
        nextBtn = driver.find_element_by_css_selector(".pageNumberBlock .down")
        if "active" in nextBtn.get_attribute("class"):
            nextBtn.click()
        else:
            hasMorePages = False
        
        time.sleep(1)

time.sleep(4)

# Close the browser.
driver.quit()