Question

我是python中的新手程序员。我目前正在构建一个解析日志文件并完成该类所有元素的类。尽管如此，因为python中的大多数东西已经消失了，我要么错误地格式化了我的类，要么搞砸了我的语义。我想知道是否有一个确定的格式来构建类，以及我写的是否遵循所述格式。

以下是日志中的一些行：

2012-06-12 14:02:21,813 [main]  INFO  ConnectionManager.java (line 238) Initializing the ConnectionManager.
2012-06-12 14:02:21,844 [main]  INFO  CimListener.java (line 142) Starting listener at http://127.0.0.1:7012
2012-06-12 14:02:21,974 [main]  INFO  CimListener.java (line 158) Listening at http://127.0.0.1:7012
2012-06-12 14:02:23,209 [main]  INFO  RmiServiceExporter.java (line 393) Looking for RMI registry at port '10099'
2012-06-12 14:02:23,232 [main]  INFO  RmiServiceExporter.java (line 404) Could not detect RMI registry - creating new one

这是班级：

import re
import time
import calendar
from datetime import datetime

f = open("C:\Users\-----\Desktop\Real Logs\controllersvc.log", "r")
while True:
    line = f.readline()
    if not line:
        break

class LogLine:

    SEVERITIES = ['EMERG','ALERT','CRIT','ERR','WARNING','NOTICE','INFO','DEBUG']
    severity = 1


    def __init__(self, line):
        try:
            timestr, msstr, sevstr, self.filename, linestr, self.message = re.match(r"^(\d\d\d\d-\d\d-\d\d[ \t]\d\d:\d\d:\d\d),(\d\d\d),(?i[a-z]+),([A-Za-z]{1,.}),([(]\[lL]ine\>\s+\d+[)]),^(?<=\)\s?\w+$)", line).groups()
            self.line = int(linestr)
            self.sev = self.SEVERITIES.index(sevstr)
            self.time = float(calendar.timegm(time.strptime(timestr, "%Y-%m-%d %H:%M:%S,%f"))) + float(msstr)/1000.0
            dt = datetime.strptime(t, "%Y-%m-%d %H:%M:%S,%f")
        except Exception:
            print 'error',self.filename

    def get_time(self):
        return self.time
    def get_severity(self):
        return self.sev
    def get_message(self):
        return message
    def get_filename(self):
        return filename
    def get_line(self):
        return line

Answer 1

您的代码有几个问题：

self.filename属性在 init
你应该尝试更具体地说明你期望捕获的异常（你想要禁止的是KeyboardInterruptException吗？）
你的正则表达很复杂，很难维护（我认为错了）
您正在将“getters”暴露给对象的公共属性，这是不必要的。
一些“getters”返回全局变量（消息，行和文件名），这些变量可能是为了返回实例属性
新编写的类理想情况下应该是某些东西（在本例中为object）

我希望这份清单有用，并被视为建设性的批评。

为了帮助您看到更多的pythonic代码，我为您的数据编写了一个日志阅读器，它没有复杂的正则表达式，也没有任何“getters”（如果您真的需要可以添加）。可以进一步简化（例如使用namedtuple），但为了清晰和教育，我保留了香草：

import datetime


class LogEntry(object):
    @staticmethod
    def from_str(line):
        """Converts a log line in a string, into a LogEntry."""
        # split the line by one or more spaces
        date, time, _, severity, filename, _, line, message = re.split('\s+', line, 7)

        # strip the trailing bracket on the line and cast to an int
        line = int(line[:-1])

        # combine the date and time strings and turn them into a datetime
        dt = datetime.datetime.strptime(date + time, "%Y-%m-%d%H:%M:%S,%f")

        return LogEntry(dt, severity, filename, line, message)

    def __init__(self, dt, severity, filename, line_num, message):
        self.datetime = dt
        self.severity = severity
        self.filename = filename
        self.line_num = line_num
        self.message = message

    def __str__(self):
        return '%s %s %s L%s: %s' % (self.datetime, self.severity, self.filename, self.line_num, self.message)


if __name__ == '__main__':

    log_contents = """2012-06-12 14:02:21,813 [main]  INFO  ConnectionManager.java (line 238) Initializing the ConnectionManager.
    2012-06-12 14:02:21,844 [main]  INFO  CimListener.java (line 142) Starting listener at http://127.0.0.1:7012
    2012-06-12 14:02:21,974 [main]  INFO  CimListener.java (line 158) Listening at http://127.0.0.1:7012
    2012-06-12 14:02:23,209 [main]  INFO  RmiServiceExporter.java (line 393) Looking for RMI registry at port '10099'
    2012-06-12 14:02:23,232 [main]  INFO  RmiServiceExporter.java (line 404) Could not detect RMI registry - creating new one"""

    # uncomment for real log reading
    #fh = file(filename, 'r')

    # emulate a log file by providing an iterable of lines (just like fh will do)
    fh = log_contents.split('\n')

    for line in fh:
        print LogEntry.from_str(line.strip())

产生输出：

2012-06-12 14:02:21.813000 INFO ConnectionManager.java L238: Initializing the ConnectionManager.
2012-06-12 14:02:21.844000 INFO CimListener.java L142: Starting listener at http://127.0.0.1:7012
2012-06-12 14:02:21.974000 INFO CimListener.java L158: Listening at http://127.0.0.1:7012
2012-06-12 14:02:23.209000 INFO RmiServiceExporter.java L393: Looking for RMI registry at port '10099'
2012-06-12 14:02:23.232000 INFO RmiServiceExporter.java L404: Could not detect RMI registry - creating new one

我真的希望这可以帮助你发现Python有多么有趣！

类格式问题

1 个答案: