Parse error log and send email
November 4th, 2008
This post gives an example of how I wrote a script that parsed an error log looking for ‘Traceback’ errors and emailing them to the admin on a daily basis. The cool thing about this script is that it keeps a byte track of each time it reads the log file, stores that byte count in a temp file then picks up at the byte count the next day so you don’t get duplicate emails from tracebacks on a previous day…
let’s call this file tracebacks.py
#!/usr/bin/python
import os
import sys
import time
import smtplib
import socket #required to get host name
from email.mime.text import MIMEText #need this for subject line in email
def main():
line=""
line_num=0
last_byte_read=""
byte_num=""
stored_byte_num=""
traceback_count=0
log_file=open("/var/log/loadscript/<logfilename here>","r")
tmp_file="/tmp/loadscript.tmp"
###############################
#check if required file exists
###############################
if os.path.exists(tmp_file):
writefile = open(tmp_file,'r')
stored_byte_num=writefile.read()
else:
writefile = open(tmp_file,'w')
writefile.write("")
writefile.close()
writefile = open(tmp_file,'r')
################################
# find last byte searched in file
################################
if len(stored_byte_num)>0:
stored_byte_num=int(stored_byte_num)
log_file.seek(stored_byte_num)
data = log_file.readlines()
was_found=False
#loop through file
for x in data:
#print x.strip()
line_num=line_num + 1
if x.startswith('Traceback'):
traceback_count += 1
line += "\n+++++++++++++++++++++++++++++++++++++++"
#########################################################"
line += "\nError on Line: %s\n" % line_num
line += "\n"+x
was_found=True
if was_found:
if x.find('File')==2:
line += x
else:
was_found = False
# record last byte read in tmp file
last_byte_read=log_file.tell()
last_byte_read=str(last_byte_read)
handle=open(tmp_file,'w')
handle.write(last_byte_read)
handle.close()
#print last_byte_read
#send mail summary
if was_found==False:
mail_message = "\nDid not find any Tracebacks!\n"
else:
mail_message = "SCRIPT SUMMARY\n"
mail_message += "================================================\n"
mail_message += "Tracebacks found: %s\n" % traceback_count
mail_message += "Last byte checked: %s\n" % last_byte_read
mail_message += "Script will start at this number next search!\n"
mail_message += "================================================\n"
mail_message += line
send_mail(mail_message)
print "Errors found and sent to pse-admin"
#print "%s" % mail_message
def send_mail(mail_message):
smtpserver='smtp.example.com'
host = socket.gethostname()
RECIPIENTS = ['username@domain.com']
SENDER = ‘root@%s.mascorp.com’ % host
MESSAGE = “”"Subject: [Nagios] Loadscript Errors
From: nagios@%s.mascorp.com
%s
“”" % (host, mail_message)
session = smtplib.SMTP(smtpserver)
smtpresult = session.sendmail(SENDER, RECIPIENTS, MESSAGE)
session.close()
try:
main()
except:
health = ‘UNKNOWN’
result = 3
print “Error: Check script”
sys.exit(1)