Django Slack Logger

01_info

This Gist supplements article available at https://serafin.io/article/slack-django-errors

02_slack_logger.py

import requests
import json
import time
import math
from copy import copy
from django.conf import settings
from django.utils.log import AdminEmailHandler
from django.views.debug import ExceptionReporter

class SlackExceptionHandler(AdminEmailHandler):

  # replacing default django emit (https://github.com/django/django/blob/master/django/utils/log.py)
  def emit(self, record, *args, **kwargs):

    # original AdminEmailHandler "emit" method code (but without actually sending email)
    try:
      request = record.request
      subject = '%s (%s IP): %s' % (
        record.levelname,
        ('internal' if request.META.get('REMOTE_ADDR') in settings.INTERNAL_IPS
         else 'EXTERNAL'),
        record.getMessage()
      )
    except Exception:
      subject = '%s: %s' % (
        record.levelname,
        record.getMessage()
      )
      request = None
    subject = self.format_subject(subject)

    # Since we add a nicely formatted traceback on our own, create a copy
    # of the log record without the exception data.
    no_exc_record = copy(record)
    no_exc_record.exc_info = None
    no_exc_record.exc_text = None

    if record.exc_info:
      exc_info = record.exc_info
    else:
      exc_info = (None, record.getMessage(), None)

    reporter = ExceptionReporter(request, is_email=True, *exc_info)
    message = "%s\n\n%s" % (self.format(no_exc_record), reporter.get_traceback_text())
    html_message = reporter.get_traceback_html() if self.include_html else None

    #self.send_mail(subject, message, fail_silently=True, html_message=html_message)
   
    # this is where original "emit" method code ends
   
  
  

    # construct slack attachment detail fields
    attachments =  [
      {
        'title': subject,
        'color': 'danger',
        'fields': [
          {
            "title": "Level",
            "value": record.levelname,
            "short": True,
          },
          {
            "title": "Method",
            "value": request.method if request else 'No Request',
            "short": True,
          },
          {
            "title": "Path",
            "value": request.path if request else 'No Request',
            "short": True,
          },
          {
            "title": "User",
            "value": ( (request.user.username + ' (' + str(request.user.pk) + ')'
                     if request.user.is_authenticated else 'Anonymous' )
                     if request else 'No Request' ),
            "short": True,
          },
          {
            "title": "Status Code",
            "value": record.status_code,
            "short": True,
          },
          {
            "title": "UA",
            "value": ( request.META['HTTP_USER_AGENT']
                     if request and request.META else 'No Request' ),
            "short": False,
          },
          {
            "title": 'GET Params',
            "value": json.dumps(request.GET) if request else 'No Request',
            "short": False,
          },
          {
            "title": "POST Data",
            "value": json.dumps(request.POST) if request else 'No Request',
            "short": False,
          },
        ],
      },

    ]


    # add main error message body

    # slack message attachment text has max of 8000 bytes
    # lets split it up into 7900 bytes long chunks to be on the safe side

    split = 7900
    parts = range( math.ceil( len( message.encode('utf8') ) / split ) )

    for part in parts:

      start = 0     if part == 0 else split * part
      end   = split if part == 0 else split * part + split

      # combine final text and prepend it with line breaks
      # so the details in slack message will fully collapse
      detail_text = '\r\n\r\n\r\n\r\n\r\n\r\n\r\n' + message[start:end]

      attachments.append({
        'color': 'danger',
        'title': 'Details (Part {})'.format(part + 1),
        'text': detail_text,
        'ts': time.time(),
      })

      
    # construct main text
    main_text = 'Error at ' + time.strftime("%A, %d %b %Y %H:%M:%S +0000", time.gmtime())
    
    # construct data
    data = {
      'payload': json.dumps({'main_text': main_text,'attachments': attachments}),
    }
    
    
    # setup channel webhook
    webhook_url = 'https://hooks.slack.com/services/xxx/xxx/xxx'
    
    # send it
    r = requests.post(webhook_url, data=data)

    

03_settings.py

from django.utils.log import DEFAULT_LOGGING

LOGGING = DEFAULT_LOGGING

LOGGING['handlers']['slack_admins'] = {
  'level': 'ERROR',
  'filters': ['require_debug_false'],
  'class': 'config.helpers.slack_logger.SlackExceptionHandler',
}

LOGGING['loggers']['django'] = {
  'handlers': ['console', 'slack_admins'],
  'level': 'INFO',
}

This line
"value": json.dumps(request.POST) if request else 'No Request',
https://gist.github.com/DominikSerafin/0e14ea2ea60022201c9a0c04454a2926#file-a-slack_logger-py-L100
is realy dangerous. E.g. password filled forms will be exposed to Slack in cleartext

Hey, @Speedy1991 I'm not 100% sure it will work (since it was long time ago when I wrote this), but I subclassed AdminEmailHandler and used its emit method from Django standard email reporting and Django sensitive information filtering should work in this logger just as in email reporting - https://docs.djangoproject.com/en/1.11/howto/error-reporting/#filtering-sensitive-information

Do you find that this is still working with Django 2.1? I was running a modified version of this successfully until upgrading to 2.1.

RE: https://gist.github.com/DominikSerafin/0e14ea2ea60022201c9a0c04454a2926#gistcomment-2755644

@chasetb
I think I'm having the same issue, as in, somehow the SlackExceptionHandler is not getting invoked/called.
Did you find any workaround for Django version > 2.1?

Third that - I am have issues with Django 2.2. SlackExceptionHandler is not getting invoked...

@aljiwala I have made this work by changing the LOGGING dict in settings:

import logging.config
LOGGING_CONFIG = None

logging.config.dictConfig({
'version': 1,
'disable_existing_loggers': False,
'formatters': {
'console': {
# exact format is not important, this is the minimum information
'format': '%(asctime)s %(name)-12s %(levelname)-8s %(message)s',
},
},
'handlers': {
'console': {
'class': 'logging.StreamHandler',
'formatter': 'console',
},
# Add Handler for Slack for warning and above
'slack': {
'level': 'WARNING',
'class': 'your_file_path.slack_logger.SlackExceptionHandler',
},
},
'loggers': {
'': {
'level': 'WARNING',
'handlers': ['console', 'slack'],
},
'app_name': {
'level': 'INFO',
'handlers': ['console', 'slack'],
# required to avoid double logging with root logger
'propagate': False,
},
},
})

@op1490 & @aljiwala I also had to overwrite the LOGGING dict to get it to work.