slacker_log_handler

Python log handler that posts to a Slack channel. Posts to the Slack API using https://github.com/os/slacker.

For a different implementation using webhooks instead of Slacker, see https://github.com/claudetech/python-slack-log or read http://www.pythian.com/blog/logging-for-slackers/

Created with the intention of using for a Django project, but some effort has been made to make it generic enough that any Python project could use it.

Installation

pip install slacker-log-handler

Options

api_key (required)

Generate a key at https://api.slack.com/

channel (required)

Set which channel you want to post to, e.g. "#general".

username

The username that will post to Slack. Defaults to "Python logger".

icon_url

URL to an image to use as the icon for the logger user

icon_emoji

emoji to use as the icon. Overrides icon_url. If neither icon_url nor icon_emoji is set, ❗ will be used.

fail_silent

Defaults to False. If your API key is invalid or for some other reason the API call returns an error, this option will silently ignore the API error. If you enable this setting, make sure you have another log handler that will also handle the same log events, or they may be lost entirely.

Django configuration

Logging reference: https://docs.djangoproject.com/en/stable/topics/logging/

This example will send INFO and ERRORS to Slack, as well as errors to admin emails.

• Set SLACK_API_KEY in your settings module.

LOGGING = {
    'version': 1,
    'disable_existing_loggers': False,
    'filters': {
        'require_debug_false': {
            '()': 'django.utils.log.RequireDebugFalse'
        }
    },
    'handlers': {
        'mail_admins': {
            'level': 'ERROR',
            'filters': ['require_debug_false'],
            'class': 'django.utils.log.AdminEmailHandler'
        },
        'slack-error': {
            'level': 'ERROR',
            'api_key': SLACK_API_KEY,
            'class': 'slacker_log_handler.SlackerLogHandler',
            'channel': '#general'
        },
        'slack-info': {
            'level': 'INFO',
            'api_key': SLACK_API_KEY,
            'class': 'slacker_log_handler.SlackerLogHandler',
            'channel': '#general'
        },
        'loggers': {
            'django.request': {
                'handlers': ['mail_admins', 'slack-error', 'slack-info'],
                'level': 'ERROR',
                'propagate': True,
            },
        }
    }
}

Example Python logging handler

This is how you use slacker_log_handler as a regular Python logging handler. This example will send a error message to a slack channel.

import logging
from slacker_log_handler import SlackerLogHandler, NoStacktraceFormatter

# Create slack handler
slack_handler = SlackerLogHandler('my-channel-token', 'my-channel-name', stack_trace=True)

# Create logger
logger = logging.getLogger('debug_application')
logger.addHandler(slack_handler)

# OPTIONAL: Define a log message formatter.
# If you have set stack_trace=True, any exception stack traces will be included as Slack message attachments.
# You therefore need to use NoStacktraceFormatter as a base to exclude the trace from the main message text.
formatter = NoStacktraceFormatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
slack_handler.setFormatter(formatter)

# Define the minimum level of log messages you want to send to Slack
slack_handler.setLevel(logging.DEBUG)

# Test logging
logger.error("Debug message from slack!")

Slack message formatting

This example use a subclass that will send a formatted message to a slack channel. Reference: https://api.slack.com/docs/message-formatting

class CustomLogHandler(SlackerLogHandler):
    def build_msg(self, record):
        message = "> New message :\n" + record.getMessage()
        return message

License

Apache 2.0

Slacker is also under Apache 2.0.

See also: https://api.slack.com/terms-of-service