使用 Python 抓取网页:让我的网页抓取代码更快?

时间:2021-03-29 20:05:26

标签: python pandas web-scraping

我想从 2 个链接中抓取两个表。我的代码是:

import pandas as pd
import xlwings as xw
from datetime import datetime

def last_row(symbol, name):

    # Function that outputs if the last row of the df should be deleted or not, 
    # based on the 2 requirements below.

    requirements = [symbol.lower()=="total", name.isdigit()]
    return all(requirements)
    
    # return True, if the last row should be deleted.
    # The deletion will be performed in the next function.

def get_foreigncompanies_info():
    df_list = []
    links = ["https://stockmarketmba.com/nonuscompaniesonusexchanges.php",
              "https://stockmarketmba.com/listofadrs.php"]
    for i in links:

        #Reads table with pandas read_html and only save the necessary columns.

        df = pd.read_html(i)[0][['Symbol', 'Name', 'GICS Sector']] 
        if last_row(df.iloc[-1]['Symbol'], df.iloc[-1]['Name']):

            # Delete the last row

            df_list.append(df.iloc[:-1])
        else:

            # Keep last row

            df_list.append(df)
    return pd.concat(df_list).reset_index(drop=True).rename(columns={'Name': 'Security'})

def open_in_excel(dataframe):  # Code to view my df in excel.
    xw.view(dataframe)
    
if __name__ == "__main__":
    start = datetime.now()
    df = get_foreigncompanies_info()
    print(datetime.now() - start)
    open_in_excel(get_foreigncompanies_info())

花了 enter image description here 秒执行代码。

我想让代码运行得更快(在某种程度上,这不会产生太多不必要的请求)。 我的想法是将表格下载为 csv,因为在网站上,有一个“下载 csv”按钮。

enter image description here

我如何用 python 下载 csv?

我检查了按钮,但找不到它的网址。 (如果你能找到它,还请描述你是如何找到它的,也许是“检查”屏幕截图。)

或者有其他更快的方法来下载表格吗?

谢谢你的指点:-)

1 个答案:

答案 0 :(得分:1)

您可以使用 selenium 自动点击按钮。这并不难,但要为如此微不足道的事情付出很多努力。我不喜欢刮,但有时我们只有刮,对吗?