Question

我正在进行股票预测项目。我想从Yahoo Finance下载历史数据并将其保存为CSV格式。

由于我是Python的初学者，因此无法纠正错误。

我的代码如下：

    import re
import urllib2
import calendar
import datetime
import getopt
import sys
import time

crumble_link = 'https://finance.yahoo.com/quote/{0}/history?p={0}'
crumble_regex = r'CrumbStore":{"crumb":"(.*?)"}'
cookie_regex = r'Set-Cookie: (.*?); '
quote_link = 'https://query1.finance.yahoo.com/v7/finance/download/{}?period1={}&period2={}&interval=1d&events=history&crumb={}'


def get_crumble_and_cookie(symbol):
    link = crumble_link.format(symbol)
    response = urllib2.urlopen(link)
    match = re.search(cookie_regex, str(response.info()))
    cookie_str = match.group(1)
    text = response.read()
    match = re.search(crumble_regex, text)
    crumble_str = match.group(1)
    return crumble_str, cookie_str


def download_quote(symbol, date_from, date_to):
    time_stamp_from = calendar.timegm(datetime.datetime.strptime(date_from, "%Y-%m-%d").timetuple())
    time_stamp_to = calendar.timegm(datetime.datetime.strptime(date_to, "%Y-%m-%d").timetuple())

    attempts = 0
    while attempts < 5:
        crumble_str, cookie_str = get_crumble_and_cookie(symbol)
        link = quote_link.format(symbol, time_stamp_from, time_stamp_to, crumble_str)
        #print link
        r = urllib2.Request(link, headers={'Cookie': cookie_str})

        try:
            response = urllib2.urlopen(r)
            text = response.read()
            print "{} downloaded".format(symbol)
            return text
        except urllib2.URLError:
            print "{} failed at attempt # {}".format(symbol, attempts)
            attempts += 1
            time.sleep(2*attempts)
    return ""

if __name__ == '__main__':
    print get_crumble_and_cookie('KO')
    from_arg = "from"
    to_arg = "to"
    symbol_arg = "symbol"
    output_arg = "o"
    opt_list = (from_arg+"=", to_arg+"=", symbol_arg+"=")
    try:
        options, args = getopt.getopt(sys.argv[1:],output_arg+":",opt_list)
    except getopt.GetoptError as err:
        print err

    for opt, value in options:
        if opt[2:] == from_arg:
            from_val = value
        elif opt[2:] == to_arg:
            to_val = value
        elif opt[2:] == symbol_arg:
            symbol_val = value
        elif opt[1:] == output_arg:
            output_val = value

    print "downloading {}".format(symbol_val)
    text = download_quote(symbol_val, from_val, to_val)

    with open(output_val, 'wb') as f:
        f.write(text)
    print "{} written to {}".format(symbol_val, output_val)

我收到的错误消息是：

File "C:/Users/Murali/PycharmProjects/generate/venv/tcl/generate2.py", line 
49, in <module>
print get_crumble_and_cookie('KO')
File "C:/Users/Murali/PycharmProjects/generate/venv/tcl/generate2.py", line 
19, in get_crumble_and_cookie
cookie_str = match.group(1)
AttributeError: 'NoneType' object has no attribute 'group'

那么我们如何解决这个突然出现的问题？

Answer 1

看看这两个命令：

match = re.search(cookie_regex, str(response.info()))
cookie_str = match.group(1)

第一个使用字符串response.info()进行正则表达式搜索以匹配cookie_regex。然后match.group(1)应该从中获得比赛。但是，问题在于，如果您在这两个命令之间执行print match，则会看到re.search()没有返回任何内容。这意味着match.group（）没有什么可“分组”的，这就是为什么它会出错。

如果您仔细查看response.info()（您可以在脚本中添加一个print response.info()命令来查看它），您会发现响应代码中有一行以“ set-cookie：”，您要尝试捕获的代码。但是，您已设置cookie_regex字符串以查找带有“ S et- C ookie：”的行。注意大写字母。当我将该字符串更改为小写时，错误消失了：

cookie_regex = r'set-cookie: (.*?); '

此后，我确实遇到了另一个错误，由于未定义print "downloading {}".format(symbol_val)，symbol_val停止了。看来此变量仅在opt[2:] == symbol_arg:时声明和分配。因此，您可能需要重写该部分以涵盖所有情况。

cookie_str = match.group（1）.AttributeError：“ NoneType”对象没有属性“ group”

1 个答案: