Many web/mobile applications generate huge amount of event logs (c,f. login, logout, purchase, follow, etc). To analyze these event logs could be really valuable for improving the service. However, the challenge is collecting these logs easily and reliably.
Fluentd solves that problem by having: easy installation, small footprint, plugins, reliable buffering, log forwarding, etc.
fluent-logger-python is a Python library, to record the events from Python application.
- Python 2.6 or greater including 3.x
This library is distributed as 'fluent-logger' python package. Please execute the following command to install it.
$ pip install fluent-loggerFluentd daemon must be launched with a tcp source configuration:
<source> type forward port 24224 </source>
To quickly test your setup, add a matcher that logs to the stdout:
<match app.**> type stdout </match>
First, you need to call logger.setup() to create global logger
instance. This call needs to be called only once, at the beggining of
the application for example.
By default, the logger assumes fluentd daemon is launched locally. You can also specify remote logger by passing the options.
from fluent import sender
# for local fluent
sender.setup('app')
# for remote fluent
sender.setup('app', host='host', port=24224)Then, please create the events like this. This will send the event to fluent, with tag 'app.follow' and the attributes 'from' and 'to'.
from fluent import event
# send event to fluentd, with 'app.follow' tag
event.Event('follow', {
'from': 'userA',
'to': 'userB'
})This client-library also has FluentHandler class for Python logging
module.
import logging
from fluent import handler
custom_format = {
'host': '%(hostname)s',
'where': '%(module)s.%(funcName)s',
'type': '%(levelname)s',
'stack_trace': '%(exc_text)s'
}
logging.basicConfig(level=logging.INFO)
l = logging.getLogger('fluent.test')
h = handler.FluentHandler('app.follow', host='host', port=24224)
formatter = handler.FluentRecordFormatter(custom_format)
h.setFormatter(formatter)
l.addHandler(h)
l.info({
'from': 'userA',
'to': 'userB'
})
l.info('{"from": "userC", "to": "userD"}')
l.info("This log entry will be logged with the additional key: 'message'.")You can also customize formatter via logging.config.dictConfig
import logging.config
import yaml
with open('logging.yaml') as fd:
conf = yaml.load(fd)
logging.config.dictConfig(conf['logging'])A sample configuration logging.yaml would be:
logging:
version: 1
formatters:
brief:
format: '%(message)s'
default:
format: '%(asctime)s %(levelname)-8s %(name)-15s %(message)s'
datefmt: '%Y-%m-%d %H:%M:%S'
fluent_fmt:
'()': fluent.handler.FluentRecordFormatter
format:
level: '%(levelname)s'
hostname: '%(hostname)s'
where: '%(module)s.%(funcName)s'
handlers:
console:
class : logging.StreamHandler
level: DEBUG
formatter: default
stream: ext://sys.stdout
fluent:
class: fluent.handler.FluentHandler
host: localhost
port: 24224
tag: test.logging
formatter: fluent_fmt
level: DEBUG
null:
class: logging.NullHandler
loggers:
amqp:
handlers: [null]
propagate: False
conf:
handlers: [null]
propagate: False
'': # root logger
handlers: [console, fluent]
level: DEBUG
propagate: FalseTesting can be done using nose.
Patches contributed by those people.
Apache License, Version 2.0