将包含日期时间的分组熊猫数据框绘制到单个时间轴中

我正在尝试解析一个日志文件（特别是从Gradle构建），如下所示：

21:51:38.991 [DEBUG] [TestEventLogger] cha.LoginTest4 STARTED
21:51:39.054 [DEBUG] [TestEventLogger] cha.LoginTest2 STARTED
21:51:40.068 [DEBUG] [TestEventLogger] cha.LoginTest4 PASSED
21:51:40.101 [DEBUG] [TestEventLogger] cha.LoginTest2 PASSED
21:51:40.366 [DEBUG] [TestEventLogger] cha.LoginTest1 STARTED
21:51:40.413 [DEBUG] [TestEventLogger] cha.LoginTest3 STARTED
21:51:50.435 [DEBUG] [TestEventLogger] cha.LoginTest1 PASSED
21:51:50.463 [DEBUG] [TestEventLogger] cha.LoginTest3 PASSED
21:51:50.484 [DEBUG] [TestEventLogger] Gradle Test Run :test PASSED
21:51:38.622 [DEBUG] [TestEventLogger] Gradle Test Run :test STARTED

到显示事件时间表的图表中。有点像这样：

n |  ======= 
a |   === 
m |       == 
e |    ======= 
  |______________
     time

到目前为止，我已经解析了日志并将相关的“事件”放入Pandas数据框（按时间戳排序）。

log events parsed, sorted and ungrouped:
                 timestamp            name
0 1900-01-01 21:51:38.622            test
0 1900-01-01 21:51:38.991  cha.LoginTest4
0 1900-01-01 21:51:39.054  cha.LoginTest2
0 1900-01-01 21:51:40.068  cha.LoginTest4
0 1900-01-01 21:51:40.101  cha.LoginTest2
0 1900-01-01 21:51:40.366  cha.LoginTest1
0 1900-01-01 21:51:40.413  cha.LoginTest3
0 1900-01-01 21:51:50.435  cha.LoginTest1
0 1900-01-01 21:51:50.463  cha.LoginTest3
0 1900-01-01 21:51:50.484            test

因为我需要每个“名称”的开始和结束时间，所以我做了一个groupby。我得到的组看起来像这样：

group                 timestamp            name
0       1900-01-01 21:51:38.991  cha.LoginTest4
0       1900-01-01 21:51:40.068  cha.LoginTest4

总会有两行，第一行是开始时间，最后一行是结束时间。我尽可能hlines地展示了每个小组的时间表。但是，我想将所有组放入同一图，以了解它们何时开始/结束彼此之间的关系。我仍然想使用groupby它，因为它使我可以用几行代码来获得开始/结束时间以及“名称”。

我最多只能显示每个组的绘图，而不是全部显示，而不会出错。这是我显示每个情节的步骤：

for name, group in df.groupby('name', sort=False):

    group.amin = group['timestamp'].iloc[0] # assume sorted order
    group.amax = group['timestamp'].iloc[1]

    fig = plt.figure()
    ax = fig.add_subplot(111)
    ax = ax.xaxis_date()
    ax = plt.hlines(group.index, dt.date2num(group.amin), dt.date2num(group.amax))

    plt.show()

已解决完整来源：

import os
import re
import pandas as pd
from pandas import Timestamp
import matplotlib.pyplot as plt
import matplotlib.dates as dt
import warnings
from random import random
from matplotlib.pyplot import text
from datetime import datetime
import numpy as np

warnings.simplefilter(action='ignore', category=FutureWarning) # https://stackoverflow.com/a/46721064

'''
The log contents are not guaranteed to be in order. Multiple processes are dumping contents into a single file.
Contents from a single process will be in order.
'''

def main():

    log_file_path = "gradle-4.2.test.debug.log"

    # regex to get test and task log events
    test_re = re.compile('^(\S+) \[DEBUG\] \[TestEventLogger\] (\S+[^:>]) (STARTED|PASSED|FAILED)$')
    task_re = re.compile('^(\S+) \[DEBUG\] \[TestEventLogger\] Gradle Test Run [:](\S+) (STARTED|PASSED|FAILED)$')

    df = pd.DataFrame()
    with open(log_file_path, "r") as file:
        for line in file:
            test_match = test_re.findall(line)
            if test_match:
                df = df.append(test_match)
            else:
                task_match = task_re.findall(line)
                if task_match:
                    df = df.append(task_match)

    file.close()

    df.columns = ['timestamp','name','type']
    df.drop('type', axis=1, inplace=True) # don't need this col
    df['timestamp'] = pd.to_datetime(df.timestamp, format="%H:%M:%S.%f") # pandas datetime
    df =  df.sort_values('timestamp')  # sort by  pandas datetime

    print ("log events parsed, sorted and ungrouped:\n", df)

    fig, ax = plt.subplots()
    ax.xaxis_date()

    # Customize the major grid
    ax.minorticks_on()
    ax.grid(which='major', linestyle='-', linewidth='0.2', color='gray')

    i = 0 # y-coord will be loop iteration

    # Groupby name. Because the df was previously sorted, the tuple will be sorted order (first event, second event)
    # Give each group an hline.
    for name, group in df.groupby('name', sort=False):
        i += 1

        assert group['timestamp'].size == 2 # make sure we have a start & end time for each test/task
        group.amin = group['timestamp'].iloc[0] # assume sorted order
        group.amax = group['timestamp'].iloc[1]
        assert group.amin < group.amax # make sure start/end times are in order

        if '.' in name: # assume '.' indicates a JUnit test, not a task
            color = [(random(),random(),random())]
            linestyle = 'solid'
            ax.text(group.amin, (i + 0.05), name, color='blue') # add name to x, y+.05 to hline
        else: # a task.
            color = 'black'
            linestyle = 'dashed'
            ax.text(group.amin, (i + 0.05), name + ' (Task)', color='red') # add name to x, y+.05 to hline

        ax.hlines(i, dt.date2num(group.amin), dt.date2num(group.amax), linewidth = 6, color=color, linestyle=linestyle)

    # Turn off y ticks. These are just execution order (numbers won't make sense).
    plt.setp(ax.get_yticklabels(), visible=False)
    ax.yaxis.set_tick_params(size=0)
    ax.yaxis.tick_left()

    plt.title('Timeline of Gradle Task and Test Execution')
    plt.xlabel('Time')
    plt.ylabel('Execution Order')
    plt.show()
#    plt.savefig('myfig')


if __name__ == '__main__':
    main()

那么，如何将充满时间戳的分组数据框放到一个显示开始/结束时间轴的图表中？

似乎我正遇到正则表达式，数据帧，日期时间等一个或另一个问题，但我认为我得到了一个很好的解决方案...。