# A Python structured logger for Fluentd
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](http://github.com/fluent/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.
## Requirements
* Python 2.6 or greater including 3.x
## Installation
This library is distributed as 'fluent-logger' python package. Please execute the following command to install it.
$ pip install fluent-logger
## Configuration
Fluentd daemon must be lauched with the following configuration:
<source>
type tcp
port 24224
</source>
<match app.**>
type stdout
</match>
## Usage
### Event-Based Interface
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'
})
### Python logging.Handler interface
This client-library also has FluentHanler class for Python logging module.
import logging
from fluent import handler
logging.basicConfig(level=logging.INFO)
l = logging.getLogger('fluent.test')
l.addHandler(handler.FluentHandler('app.follow', host='host', port=24224))
l.info({
'from': 'userA',
'to': 'userB'
})
### Pyramid logging configuration
First, setup a fluent log formatter.
Note the different format of "format".
[formatter_fluent]
class = fluent.handler.FluentRecordFormatter
format =
levelname
name
#datefmt = %H:%M:%S (fluentd native date format is used instead)
Then, setup a fluent handler.
class = fluent.handler.FluentHandler
args = ("<Your log tag>",)
level = INFO
formatter = fluent
Finally, add the fluent handler to handler list.
[handlers]
keys = generic, fluent
## Contributors
Patches contributed by [those people](https://github.com/fluent/fluent-logger-python/contributors).
## License
Apache License, Version 2.0