Requirements

• Python 2.6, 2.7, 3.2, 3.3, pypy.

setup logger by code

import logging
import ltsvlogger

formatter = LTSVFormatter(fields={
    'asctime': 'time',
    'user': 'user',
    'host': 'host',
    'message': 'message',
})

logger = logging.getLogger('code')
hdr = logging.StreamHandler()
hdr.setLevel(logging.INFO)
hdr.setFormatter(formatter)
logger.addHandler(hdr)

# extra keyword argument values fill into format string placeholder.
# If formatter did not have 'user' and host' placeholder, these
# values will be simply omitted.
logger.error(
    'This is a error message with %s',
    'extra arguments',
    extra=dict(
        user='spam',
        host='ham.example.com',
    )
)

output sample:

host:ham.example.com\tmessage:This is a error message with extra arguments\tuser:spam\ttime:2013-09-27T09:21:03+00:00

If you want to output fields in order, you can setup formatter with fmt argument like logging.Formatter parameter:

formatter = LTSVFormatter(
    'time:%(asctime)s\tuser:%(user)s\thost:%(host)s\tmessage:%(message)s'
)

setup logger by code with LTSVLoggerAdapter

import logging
import ltsvlogger

formatter = LTSVFormatter()

logger = logging.getLogger('adapter')
hdr = logging.StreamHandler()
hdr.setLevel(logging.INFO)
hdr.setFormatter(formatter)
logger.addHandler(hdr)

# LTSVLoggerAdapter will extract keyword argument into log format.
ltsvlogger = LTSVLoggerAdapter(logger)

ltsvlogger.error(
    'This is a error message with %s',
    'keyword arguments',
     user='spam',
     host='ham.example.com',
)

output sample:

process_name:MainProcess\tlogger_name:sample\tthread_id:140654083024640\ttime:2013-09-27T08:49:53+00:00\tprocess_id:17807\tmessage:This is a error message with keyword arguments\thost:ham.example.com\tuser:spam\tthread_name:MainThread\tlog_level:ERROR

setup logger by config

Prepare logger.ini for logger:

[loggers]
keys = root,demo

[handlers]
keys = ltsvhdr

[formatters]
keys = ltsvfmt

[logger_root]
level = DEBUG
handlers =

[logger_demo]
level = DEBUG
handlers = ltsvhdr
qualname = demo

[handler_ltsvhdr]
class = StreamHandler
args = (sys.stderr,)
level = DEBUG
formatter = ltsvfmt

[formatter_ltsvfmt]
format = time:%(asctime)s\tlogger_name:%(name)s\tmessage:%(message)s
datefmt = %Y-%m-%dT%H:%M:%S%z
class = ltsvlogger.LTSVFormatter

and use:

import logging.config
logging.config.fileConfig('logger.ini')
logger = logging.getLogger('demo')

ltsvlogger = LTSVLoggerAdapter(logger)

ltsvlogger.warning(
    'This is a warning message with %s',
    'keyword arguments',
    user='spam',
    host='ham.example.com',
)

output sample:

time:2013-09-27T08:49:53+00:00\tlogger_name:demo\tmessage:This is a warning message with keyword arguments\thost:ham.example.com\tuser:spam

0.9.0 (unreleased)

First release.

• Provide ltsvlogger.LTSVFormatter

• Provide ltsvlogger.LTSFLoggerAdapter