Question

我正在使用正则表达式分析日志文件。记录示例：

<teststep timestamp="12040.310594" level="0" type="user" ident="1.2" result="pass">Signal STATUS_GET_VALUE response time Ok,\nSignal response time: 0.000000 [ms] \nSignal response time limit set: 100.000000 [ms]</teststep>

我需要提取时间戳和信号响应时间。

我解决这个问题的方法：

with open('report.xml') as f:
for line in f:
    if 'Signal response time: ' in line:
        timeStampL = re.findall('timestamp="\d*.\d*"', line)
        responseTimeL = re.findall('Signal response time: \d*.\d*',
                                   line, re.IGNORECASE)
        timeStamp = float(re.findall('\d+.\d+', timeStampL[0])[0])
        responseTime = float(re.findall('\d+.\d+', responseTimeL[0])[0])

我确信这不是获取此数据的最短和最佳方式。你想建议我一个更好的方法吗？

Answer 1

我们可以使用BeautifulSoup提取属性值和元素文本，如下所示：

由于文字值Signal STATUS_GET_VALUE response time Ok,\nSignal response time: 0.000000 [ms] \nSignal response time limit set: 100.000000 [ms]附带\n个分隔符，因此您可以将它们用于split()您的数据，并仅获取0.000000 [ms]。

<强>代码：

from bs4 import BeautifulSoup

html_code = '<teststep timestamp="12040.310594" level="0" type="user" ident="1.2" result="pass">Signal STATUS_GET_VALUE response time Ok,\nSignal response time: 0.000000 [ms] \nSignal response time limit set: 100.000000 [ms]</teststep>'

soup = BeautifulSoup(html_code, "html.parser")

for test in soup.find_all('teststep'):
    print(test.get('timestamp'))
    print(test.text.split("\n")[1].split(":")[1].strip())

<强>输出：

12040.310594
0.000000 [ms]

P.s。：您可以通过更改以下内容删除[ms]处的0.000000 [ms]：

test.text.split("\n")[1].split(":")[1].strip()

到此：

test.text.split("\n")[1].split(":")[1].strip().replace(" [ms]", "")

Answer 2

获得所需结果的另一种方法是使用像BeautifulSoup这样的XML / HTML解析器来定位元素，获取timestamp属性（在BeautifulSoup中你可以对待在读取属性时将元素作为字典）并使用正则表达式提取“信号响应时间”：

In [1]: import re

In [2]: from bs4  import BeautifulSoup

In [3]: data = """<teststep timestamp="12040.310594" level="0" type="user" ident="1.2" result="pas
    ...: s">Signal STATUS_GET_VALUE response time Ok,\nSignal response time: 0.000000 [ms] \nSignal
    ...:  response time limit set: 100.000000 [ms]</teststep>"""

In [4]: soup = BeautifulSoup(data, "html.parser")

In [5]: pattern = re.compile(r"Signal response time: ([0-9.]+)")

In [6]: elm = soup.find("teststep", text=pattern)

In [7]: print(elm["timestamp"], pattern.search(elm.get_text()).group(1))
12040.310594 0.000000

Python正则表达式缩短

2 个答案: