Parse .log file to collect data after keyword then create a nested dictionary using predefined column names - python-3.x

Question

I am trying to parse a .log file using python for the Status information about processes of a linux system. The .log file has a lot of different sections of information, the sections of interest start with "##START-ALLPROCESSES-xxxxxxxx" where x is the epoch date and end with '##END-ALLPROCESSES-xxxxxxx". After this line each process is listed with 52 columns each, the number of processes may change depending on the info recorded at the time, and there may be multiple sections with this information at different times.
The idea is to open the .log file, find the sections and then use the XXXXXXX as the key for a nested dictionary where the keys are the predefined column dates filled in with the values from the section, and do this for all different sections that would be found on the .log fie. The nested dictionary would look something like below
[date1-XXXXXX:
[ columnName1: process1,
.
.
.
columnName52: info1
],
.
.
.
[ columnName1: process52,
.
.
.
columName52: info52
]
],
[date2-XXXXXX:
[ columnName1: process1,
.
.
.
columnName52: info1
],
.
.
.
[ columnName1: process52,
.
.
.
columName52: info52
]
]
The data in the .log file looks as follow and would have multiple sections as this but with a different date each line starts with the process id and (process name)
##START-ALLPROCESSES-1676652419
1 (systemd) S 0 1 1 0 -1 4210944 2070278 9743969773 2070 2703 8811 11984 7638026 9190549 20 0 1 0 0 160043008 745 18446744073709551615 187650352414720 187650353516788 281474853505456 0 0 0 671173123 4096 1260 1 0 0 17 0 0 0 2706 0 0 187650353585800 187650353845340 187651263758336 281474853506734 281474853506745 281474853506745 281474853507053 0
10 (rcu_bh) I 2 0 0 0 -1 2129984 0 0 0 0 0 0 0 0 20 0 1 0 2 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 1 0 0 17 0 0 0 0 0 0 0 0 0 0 0 0 0 0
10251 (kworker/1:2) I 2 0 0 0 -1 69238880 0 0 0 0 0 914 0 0 20 0 1 0 617684776 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 1 0 0 17 1 0 0 0 0 0 0 0 0 0 0 0 0 0
10299 (loop2) S 2 0 0 0 -1 3178560 0 0 0 0 0 24 0 0 0 -20 1 0 10871 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 1 0 0 17 0 0 0 169 0 0 0 0 0 0 0 0 0 0
10648 (kworker/2:0) I 2 0 0 0 -1 69238880 0 0 0 0 0 567 0 0 20 0 1 0 663634994 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 1 0 0 17 2 0 0 0 0 0 0 0 0 0 0 0 0 0
1082 (nvme-wq) I 2 0 0 0 -1 69238880 0 0 0 0 0 0 0 0 0 -20 1 0 109 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 1 0 0 17 3 0 0 0 0 0 0 0 0 0 0 0 0 0
1095 (scsi_eh_0) S 2 0 0 0 -1 2129984 0 0 0 0 0 0 0 0 20 0 1 0 110 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 1 0 0 17 3 0 0 0 0 0 0 0 0 0 0 0 0 0
1096 (scsi_tmf_0) I 2 0 0 0 -1 69238880 0 0 0 0 0 0 0 0 0 -20 1 0 110 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 1 0 0 17 0 0 0 0 0 0 0 0 0 0 0 0 0 0
1099 (scsi_eh_1) S 2 0 0 0 -1 2129984 0 0 0 0 0 0 0 0 20 0 1 0 110 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 1 0 0 17 0 0 0 0 0 0 0 0 0 0 0 0 0 0
11 (migration/0) S 2 0 0 0 -1 69238848 0 0 0 0 0 4961 0 0 -100 0 1 0 2 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 1 0 0 17 0 99 1 0 0 0 0 0 0 0 0 0 0 0
1100 (scsi_tmf_1) I 2 0 0 0 -1 69238880 0 0 0 0 0 0 0 0 0 -20 1 0 110 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 1 0 0 17 0 0 0 0 0 0 0 0 0 0 0 0 0 0
##END-ALLPROCESSES-1676652419
I have tried it multiple ways but I cannot seem to get it to go correctly, my last attempt
columns = ['pid', 'comm', 'state', 'ppid', 'pgrp', 'session', 'tty_nr', 'tpgid', 'flags', 'minflt', 'cminflt', 'majflt', 'cmajflt', 'utime', 'stime',
'cutime', 'cstime', 'priority', 'nice', 'num_threads', 'itrealvalue', 'starttime', 'vsize', 'rss', 'rsslim', 'startcode', 'endcode', 'startstack', 'kstkesp',
'kstkeip', 'signal', 'blocked', 'sigignore', 'sigcatch', 'wchan', 'nswap', 'cnswap', 'exit_signal', 'processor', 'rt_priority', 'policy', 'delayacct_blkio_ticks',
'guest_time', 'cguest_time', 'start_data', 'end_data', 'start_brk', 'arg_start', 'arg_end', 'env_start', 'env_end', 'exit_code' ]
for file in os.listdir(dir):
if file.endswith('.log'):
with open(file, 'r') as f:
data = f.read()
data = data.split('##START-ALLPROCESSES-')
data = data[1:]
for i in range(len(data)):
data[i] = data[i].split('##END-ALLPROCESSES-')
data[i] = data[i][0]
data[i] = re.split('\r', data[i])
data[i] = data[i][0]
data[i] = re.split('\n', data[i])
for j in range(len(data[i])):
data[i][j] = re.split('\s+', data[i][j])
#print(data[i])
data[i][0] = str(data[i][0])
data_dict = {}
for i in range(len(data)):
data_dict[data[i][0]] = {}
for j in range(len(columns)):
data_dict[data[i][0]][columns[j]] = data[i][j+1]
print(data_dict)
I converted the epoch date into a str as I was getting unhashable list errors, however that made it so the epoch date shows as a key but each column now has the entire list for the 52 columms of information as a single one, so definitely I am missing something

Answer 1

To solve this problem, you could follow the following steps:
Open the .log file and read the contents
Search for all the sections of interest by finding lines that start with "##START-ALLPROCESSES-" and end with "##END-ALLPROCESSES-"
For each section found, extract the epoch date and create a dictionary with an empty list for each of the 52 columns
Iterate over the lines within the section and split the line into the 52 columns using space as a separator. Add the values to the corresponding list in the dictionary created in step 3
Repeat steps 3 and 4 for all the sections found in the .log file
Return the final nested dictionary
Here is some sample code that implements these steps:
import re
def parse_log_file(log_file_path):
with open(log_file_path, 'r') as log_file:
log_contents = log_file.read()
sections = re.findall(r'##START-ALLPROCESSES-(.*?)##END-ALLPROCESSES-', log_contents, re.DOTALL)
nested_dict = {}
for section in sections:
lines = section.strip().split('\n')
epoch_date = lines[0].split('-')[-1]
column_names = ['column{}'.format(i) for i in range(1, 53)]
section_dict = {column_name: [] for column_name in column_names}
for line in lines[1:]:
values = line.strip().split()
for i, value in enumerate(values):
section_dict[column_names[i]].append(value)
nested_dict['date{}-{}'.format(epoch_date, len(section_dict['column1']))] = section_dict
return nested_dict
You can call this function by passing the path to the .log file as an argument. The function returns the nested dictionary described in the problem statement.