当使用urlparser在日志文件中循环访问某些行时缺少特定参数时，如何在列表中附加null

Question

我希望通过url来解析我的文件，但是某些url缺少参数，并且当我遍历日志行时遇到了缺少参数的错误。 我需要将空白或空值添加到解析列表中，以便可以将其转换为数据框

我的数据文件：日志文件

"GET /pixel.gife=heartbeat&creative_id=33548&in_view_time=290"
"GET/pixel.gife=heartbeat&creative_id=33548&in_view_time=23988"
"GET /pixel.gif?e=heartbeat&creative_id=33548&in_view_time=19183"
"GET /pixel.gif?e=ad_load&creative_id=33548"

我希望输出为：

   E |  Creative ID | IN VIEW TIME

   heartbeat   33548    290

   heartbeat 33548 23988

   ad_load 33548 null

我的代码：

parselist = []
for eachline in log.readlines():
    ip_regex = re.findall(r'(\d{18})', eachline)
    date = re.findall(r'([0-9]{4}\-[0-9]{2}\-[0-9]{2})',eachline)
    url = eachline
    parsed = urlparse.urlparse(url)
    parselist.append(ip_regex)
    parselist.append(date)
    parselist.append(urlparse.parse_qs(parsed.query)['e'])
    parselist.append(urlparse.parse_qs(parsed.query)['account_id'])
    parselist.append(urlparse.parse_qs(parsed.query)['impression_id'])
    parselist.append(urlparse.parse_qs(parsed.query)['campaign_id'])
    parselist.append(urlparse.parse_qs(parsed.query)['creative_id'])
    parselist.append(urlparse.parse_qs(parsed.query)['in_view_time'])

我收到错误，因为第三行缺少in_view_time参数：

---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
<ipython-input-6-405c1bfb329e> in <module>()
     12     parselist.append(urlparse.parse_qs(parsed.query)['campaign_id'])
     13     parselist.append(urlparse.parse_qs(parsed.query)['creative_id'])
---> 14     parselist.append(urlparse.parse_qs(parsed.query)['in_view_time'])

KeyError: 'in_view_time'

Answer 1

您可以使用try和except ：

parselist = []
for eachline in log.readlines():
    ip_regex = re.findall(r'(\d{18})', eachline)
    date = re.findall(r'([0-9]{4}\-[0-9]{2}\-[0-9]{2})',eachline)
    url = eachline
    parsed = urlparse.urlparse(url)
    parselist.append(ip_regex)
    parselist.append(date)
    try:
        parselist.append(urlparse.parse_qs(parsed.query)['e'])
    except:
        parselist.append('Null')
    try:
        parselist.append(urlparse.parse_qs(parsed.query)['account_id'])
    except:
        parselist.append('Null')
    try:
        parselist.append(urlparse.parse_qs(parsed.query)['impression_id'])
    except:
        parselist.append('Null')
    try:
        parselist.append(urlparse.parse_qs(parsed.query)['campaign_id'])
    except:
        parselist.append('Null')
    try:
        parselist.append(urlparse.parse_qs(parsed.query)['creative_id'])
    except:
        parselist.append('Null')
    try:
        parselist.append(urlparse.parse_qs(parsed.query)['in_view_time'])
    except:
        parselist.append('Null')

或者，以更紧凑的方式：

parselist = []
for eachline in log.readlines():
    ip_regex = re.findall(r'(\d{18})', eachline)
    date = re.findall(r'([0-9]{4}\-[0-9]{2}\-[0-9]{2})',eachline)
    url = eachline
    parsed = urlparse.urlparse(url)
    parselist.append(ip_regex)
    parselist.append(date)

    for key in ['e','account_id','impression_id','campaign_id','creative_id','in_view_time']:
        try:
            parselist.append(urlparse.parse_qs(parsed.query)[key])
        except:
            parselist.append('Null')

作为建议，您可以附加None来代替'Null' 。

Answer 2

1. 为什么要创建列表（丢失密钥并仅存储值）？
2. 如果您只对这些值感兴趣，则可以简单地编写以下内容：

for v in urlparse.parse_qs(parsed.query).values():
    parselist.append(v)