pygogo 1.3.0

Description:

pygogo 1.3.0

pygogo: a Python logger with superpowers



Index
Introduction | Requirements | Motivation | Usage | Installation |
Project Structure | Design Principles | Structured Logging |
Formatters | Handlers | Scripts | Contributing | License


Introduction
pygogo is a Python logging library and command-line interface with super powers.
pygogo leverages the standard Python logging module under the hood, so there’s
no need to learn yet-another logging library. The default implementation sends
all messages to stdout, and any messages at level WARNING or above also to stderr.
With pygogo, you can

Log via different handlers depending on the event severity
Format log messages as plain text, csv, json, and more..
Send logs to stdout, stderr, file, email, sockets, and more..
Inter-operate with the standard python logging module
and much more…



Requirements
pygogo has been tested and is known to work on Python 3.7, 3.8, and 3.9; and PyPy3.7.


Motivation
The standard logging module is great, but requires a ton of boilerplate before
you can do anything really interesting with it. I designed pygogo to provide
many useful logging use-cases out of the box. A reimplementation of
Using LoggerAdapters to impart contextual information is shown below:
import pygogo as gogo

logger = gogo.Gogo(__name__).get_structured_logger(connid='1234')
logger.info('log message')

# Prints the following to stdout

{"message": "log message", "connid": "1234"}


Usage
pygogo is intended to be used either directly as a Python library or from
the terminal via the command-line interface.

Library

Examples
Hello World
from pygogo import logger

logger.debug('hello world')
logger.error('hello error')

# Prints the following to `stdout`

hello world
hello error

# Prints the following to `stderr`

hello error
Log based debugging
import pygogo as gogo

def main(verbose=False):
logger = gogo.Gogo(__name__, verbose=verbose).logger
logger.debug('I will log to `stdout` only if `verbose` is True')
logger.info('I will log to `stdout` always')
logger.warning('I will log to both `stdout` and `stderr` always')
Disabled dual logging
import pygogo as gogo

logger = gogo.Gogo(monolog=True).logger
logger.debug('debug message')
logger.info('info message')
logger.warning('warning message')
logger.error('error message')
logger.critical('critical message')

# Prints the following to `stdout.log` (all messages at level `INFO` or below):

debug message
info message

# Prints the following to `stderr` (messages at level `WARNING` or above):

warning message
error message
critical message
Custom formatter [1]
import logging
import pygogo as gogo

log_format = '%(asctime)s - %(name)s - %(levelname)s - %(message)s'
formatter = logging.Formatter(log_format)

logger = gogo.Gogo(
'examples.fmt',
low_hdlr=gogo.handlers.file_hdlr('custom_fmt.log'),
low_formatter=formatter,
high_level='error',
high_formatter=formatter).logger

# Now let's log something!

logger.debug('debug message')
logger.info('info message')
logger.warn('warn message')
logger.error('error message')
logger.critical('critical message')

# Prints the following to `custom_fmt.log` (all messages):

2015-12-18 18:51:30,416 - examples.fmt.base - DEBUG - debug message
2015-12-18 18:51:30,416 - examples.fmt.base - INFO - info message
2015-12-18 18:51:30,416 - examples.fmt.base - WARNING - warn message
2015-12-18 18:51:30,416 - examples.fmt.base - ERROR - error message
2015-12-18 18:51:30,416 - examples.fmt.base - CRITICAL - critical message

# Prints the following to `stderr` (messages at level `ERROR` or above):

2015-12-18 18:51:30,416 - examples.fmt.base - ERROR - error message
2015-12-18 18:51:30,416 - examples.fmt.base - CRITICAL - critical message
Structured logging [2]
import pygogo as gogo

formatter = gogo.formatters.structured_formatter
kwargs = {'low_level': 'info', 'low_formatter': formatter}
logger = gogo.Gogo('examples.structured', **kwargs).logger
extra = {'set_value': set([1, 2, 3]), 'snowman': '☃'}
logger.info('log message', extra=extra) # doctest: +ELLIPSIS

# Prints the following to `stdout`:

{"snowman": "\u2603", "name": "examples.structured.base", "level": "INFO", "message": "log message", "time": "2015-12-18 18:52:39", "msecs": 58.973073959350586, "set_value": [1, 2, 3]}
Using Filters to impart contextual information [3]
import logging
import pygogo as gogo

levels = ('DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL')
log_frmt = (
'%(asctime)-4s %(name)-5s %(levelname)-8s IP: %(ip)-15s User: '
'%(user)-8s %(message)s')

formatter = logging.Formatter(log_frmt)
going = gogo.Gogo('a', low_formatter=formatter)
a1 = going.get_logger('b.c', ip='123.231.231.123', user='fred')
a2 = going.get_logger('e.f', ip='192.168.0.1', user='sheila')

# Now let's log something!

a1.debug('A debug message')
a1.info('An info %s', 'message')

for level in [getattr(logging, l) for l in levels]:
name = logging.getLevelName(level)
a2.log(level, 'A %s msg', name)

# Prints the following to `stdout` (all messages):

2015-12-19 10:12:24,479 a.b.c DEBUG IP: 123.231.231.123 User: fred A debug message
2015-12-19 10:12:24,479 a.b.c INFO IP: 123.231.231.123 User: fred An info message
2015-12-19 10:12:24,479 a.e.f DEBUG IP: 192.168.0.1 User: sheila A DEBUG msg
2015-12-19 10:12:24,479 a.e.f INFO IP: 192.168.0.1 User: sheila AN INFO msg
2015-12-19 10:12:24,479 a.e.f WARNING IP: 192.168.0.1 User: sheila A WARNING msg
2015-12-19 10:12:24,479 a.e.f ERROR IP: 192.168.0.1 User: sheila AN ERROR msg
2015-12-19 10:12:24,479 a.e.f CRITICAL IP: 192.168.0.1 User: sheila A CRITICAL msg

# Prints the following to `stderr` (messages at level `WARNING` or above):

2015-12-19 10:12:24,479 a.e.f WARNING IP: 192.168.0.1 User: sheila A WARNING msg
2015-12-19 10:12:24,479 a.e.f ERROR IP: 192.168.0.1 User: sheila AN ERROR msg
2015-12-19 10:12:24,479 a.e.f CRITICAL IP: 192.168.0.1 User: sheila A CRITICAL msg
Multiple loggers [4]
import pygogo as gogo

going = gogo.Gogo(
'examples.lggrs',
low_hdlr=gogo.handlers.file_hdlr('multi_lggrs.log'),
low_formatter=gogo.formatters.fixed_formatter,
high_level='info',
high_formatter=gogo.formatters.console_formatter)

root = going.logger
logger1 = going.get_logger('area1')
logger2 = going.get_logger('area2')

# Now let's log something!

root.info('Jackdaws love my big sphinx.')
logger1.debug('Quick zephyrs blow, daft Jim.')
logger1.info('How daft jumping zebras vex.')
logger2.warning('Jail zesty vixen who grabbed pay.')
logger2.error('The five boxing wizards jump.')

# Prints the following to `multi_lggrs.log` (all messages):

2015-12-18 17:21:37.417 examples.lggrs.base INFO Jackdaws love my big sphinx.
2015-12-18 17:21:37.417 examples.lggrs.area1 DEBUG Quick zephyrs blow, daft Jim.
2015-12-18 17:21:37.417 examples.lggrs.area1 INFO How daft jumping zebras vex.
2015-12-18 17:21:37.417 examples.lggrs.area2 WARNING Jail zesty vixen who grabbed pay.
2015-12-18 17:21:37.417 examples.lggrs.area2 ERROR The five boxing wizards jump.

# Prints the following to `stderr` (messages at level `INFO` or above):

examples.lggrs.base: INFO Jackdaws love my big sphinx.
examples.lggrs.area1: INFO How daft jumping zebras vex.
examples.lggrs.area2: WARNING Jail zesty vixen who grabbed pay.
examples.lggrs.area2: ERROR The five boxing wizards jump.


Notes


[1]
https://docs.python.org/2/howto/logging-cookbook.html#multiple-handlers-and-formatters


[2]
https://docs.python.org/2/howto/logging-cookbook.html#implementing-structured-logging


[3]
https://docs.python.org/2/howto/logging-cookbook.html#using-filters-to-impart-contextual-information


[4]
https://docs.python.org/2/howto/logging-cookbook.html#logging-to-multiple-destinations





Command-line Interface
Examples
Basic Usage
gogo [options] <message>
show help
gogo -h
CLI usage

usage: gogo [options] <message>
description: Logs a given message

positional arguments:
message The message to log (defaults to reading from stdin).

optional arguments:

-h, --help
show this help message and exit

-l LEVEL, --msg-level LEVEL
The level to log the message (default: info).
Must be one of: critical, error, warning, info, debug.

-n NAME, --name NAME
The logger name (default: pygogo)

-D HANDLER, --high-hdlr HANDLER
The high pass log handler (default: stderr).
Must be one of: buffered, email, file, fileobj,
socket, stderr, stdout, syslog, webhook.

-d HANDLER, --low-hdlr HANDLER
The low pass log handler (default: stdout).
Must be one of: buffered, email, file, fileobj,
socket, stderr, stdout, syslog, webhook.

-L LEVEL, --high-level LEVEL
Min level to log to the high pass handler
(default: warning).
Must be one of: buffered, email, file, fileobj,
socket, stderr, stdout, syslog, webhook.

-e LEVEL, --low-level LEVEL
Min level to log to the low pass handler
(default: debug).
Must be one of: buffered, email, file, fileobj,
socket, stderr, stdout, syslog, webhook.

-F FORMAT, --high-format FORMAT
High pass handler log format (default: basic).
Must be one of: basic, bom, console, csv,
fixed, json, structured.

-o FORMAT, --low-format FORMAT
Low pass handler log format (default: basic).
Must be one of: basic, bom, console, csv,
fixed, json, structured.

-m, --monolog
Log high level events only to high pass handler.

-f FILENAME, --filename FILENAME
The filename to log to.
Required for the follow handlers: file.

-s SUBJECT, --subject SUBJECT
The log subject (default: You’ve got mail).
Used in the follow handlers: email.

-u URL, --url URL
The log url. Required for the follow handlers: webhook.

-H HOST, --host HOST
The host.
Used in the follow handlers: socket and syslog.

-p NUM, --port NUM
The port number.
Used in the follow handlers: socket and syslog.

-t, --tcp
Use TCP instead of UDP.
Used in the follow handlers: socket and syslog.

-g, --get
Use a GET request instead of POST.
Used in the follow handlers: webhook.

-v, --version
Show version and exit.

-V, --verbose
Increase output verbosity.





Hello World
gogo 'hello world'
Log based debugging
gogo 'default info level will log to `stdout`'
gogo --level=debug "debug won't log"
gogo --level=debug -V 'verbose will log to `stdout`'
gogo --level=info 'info will log to `stdout`'
gogo --level=warning 'warning will log to both `stdout` and `stderr`'

# Prints the following to `stdout`:

default info level will log to `stdout`
verbose will log to `stdout`
info will log to `stdout`
warning will log to both `stdout` and `stderr`

# Prints the following to `stderr`:

warning will log to both `stdout` and `stderr`
Disable dual logging
gogo --level=debug -V 'debug message'
gogo --level=info 'info message'
gogo --level=warning -m 'warning message'
gogo --level=error -m 'error message'
gogo --level=critical -m 'critical message'

# Prints the following to `stdout.log` (all messages at level `INFO` or below):

debug message
info message

# Prints the following to `stderr` (messages at level `WARNING` or above):

warning message
error message
critical message
Structured logging
gogo --low-format=json 'log message'

# Prints the following to `stdout`:

{"time": "2015-12-19 11:26:53.776", "name": "pygogo.runner", "level": "INFO", "message": "log message"}
Alternate handler
gogo --low-hdlr=file 'log message'

# Prints the following to `pygogo.log` in the current dir (assuming the current dir is named `pygogo`):

{"time": "2015-12-19 11:26:53.776", "name": "pygogo.runner", "level": "INFO", "message": "log message"}



Installation
(You are using a virtualenv, right?)
At the command line, install pygogo using either pip (recommended)
pip install pygogo
or easy_install
easy_install pygogo
Please see the installation doc for more details.


Project Structure
┌── bin
│   └── gogo
├── docs
│   ├── AUTHORS.rst
│   ├── CHANGES.rst
│   ├── INSTALLATION.rst
│   └── TODO.rst
├── helpers
│   ├── check-stage
│   ├── clean
│   ├── pippy
│   ├── srcdist
│   └── wheel
├── pygogo
│   ├── __init__.py
│   ├── formatters.py
│   ├── handlers.py
│   ├── main.py
│   └── utils.py
├── tests
│   ├── __init__.py
│   ├── standard.rc
│   ├── test.py
│   └── test_main.py
├── CONTRIBUTING.rst
├── LICENSE
├── MANIFEST.in
├── Makefile
├── README.rst
├── dev-requirements.txt
├── examples.py
├── manage.py
├── py2-requirements.txt
├── setup.cfg
├── setup.py
└── tox.ini


Design Principles

the built-in logging module isn’t broken so don’t reinvent the wheel
prefer functions over objects
keep the API as simple as possible



Structured Logging
There are severals ways to get structured (machine readable) log messages using pygogo.
Each method makes a different customization/complexity trade-off which is
outlined below:

Setup
The following methods make use of these variables.
import pygogo as gogo

kwargs = {'contextual': True}
extra = {'additional': True}


Methods

basic structured logger
The simplest to use. Useful if you don’t need message metadata, i.e., log level,
log name, and log time.
logger = gogo.Gogo('basic').get_structured_logger('base', **kwargs)
logger.debug('message', extra=extra)

# Prints the following to `stdout`:

{"additional": true, "contextual": true, "message": "message"}


structured formatter
Requires an additional step of specifying a formatter. Useful if you need
message metadata, i.e., log level, log name, and log time.
formatter = gogo.formatters.structured_formatter
logger = gogo.Gogo('struct', low_formatter=formatter).get_logger(**kwargs)
logger.debug('message', extra=extra)

# Prints the following to `stdout`:

{"additional": true, "contextual": true, "level": "DEBUG", "message": "message", "msecs": 760.5140209197998, "name": "struct.base", "time": "2015-12-19 14:25:58"}


JSON formatter
Requires an additional step of specifying a formatter. Useful if you require
millisecond precision in the date. If you are ok with having the milliseconds
in a separate field, consider the structured formatter since it supports
the extra keyword and contextual information.
formatter = gogo.formatters.json_formatter
logger = gogo.Gogo('json', low_formatter=formatter).get_logger(**kwargs)
logger.debug('message', extra=extra)

# Prints the following to `stdout`:

{"level": "DEBUG", "message": "message", "name": "json.base", "time": "2015-12-19 14:25:58.760"}

# Note that both `extra` and `kwargs` were ignored


custom logger
The most complex and customizable. Useful if you need a custom
log or date format not provided by the above methods. However, even though this
method supports the extra keyword when logging, it is static (unlike the
structured logger or structured formatter). This is because the log
format must be specified at the time of the log’s creation and therefore can’t
adapt to log messages with differing extra parameters.
logfmt = (
'{"time": "%(asctime)s.%(msecs)d", "name": "%(name)s", "level":'
' "%(levelname)s", "message": "%(message)s", '
'"contextual": "%(contextual)s", "additional": "%(additional)s"}')

fmtr = logging.Formatter(logfmt, datefmt=gogo.formatters.DATEFMT)
logger = gogo.Gogo('custom', low_formatter=fmtr).get_logger(**kwargs)
logger.debug('message', extra=extra)

# Prints the following to `stdout`:

{"additional": "True", "contextual": "True", "level": "DEBUG", "message": "message", "name": "custom.logger", "time": "2015-12-19 14:25:58.760"}



Summary
The following table can help make sense of the different methods:



structured logger
structured formatter
json formatter
custom logger



contextual information
✔
✔

✔

extra param support
✔
✔

✔

dynamic extra support
✔
✔



message metadata

✔
✔
✔

available via the command line

✔
✔


msecs field

✔



milliseconds in time field


✔
✔

custom date format



✔

custom log format



✔






Formatters
pygogo has several builtin formatters and also supports any logging.Formatter
instance.

Examples

builtin CSV format in python
import pygogo as gogo

formatter = gogo.formatters.csv_formatter
gogo.Gogo('csv', low_formatter=formatter).logger.debug('message')

# Prints the following to `stdout`:

2015-12-19 17:03:48.99,csv.base,DEBUG,"message"


logging.Formatter instance in python
import logging
import pygogo as gogo

datefmt = gogo.formatters.DATEFMT
formatter = logging.Formatter(gogo.formatters.CSV_FORMAT, datefmt=datefmt)
gogo.Gogo('csv', low_formatter=formatter).get_logger('custom').debug('message')

# Prints the following to `stdout`:

2015-12-19 17:03:48.99,csv.custom,DEBUG,"message"


builtin CSV format via CLI
gogo --low-format=csv 'message'

# Prints the following to `stdout`:

2015-12-19 15:51:32.16,pygogo.runner,INFO,"message"



Summary
The following table can help make sense of the different builtin formatters:


name
message



basic
message

bom
message

console
name: INFO message

csv
2015-12-19 15:51:32.16,name,INFO,”message”

fixed
2015-12-19 15:51:32.16 name INFO message

json
{“level”: “INFO”, “message”: “message”, “name”: “name”, “time”: “2015-12-19 15:51:32.16”}

structured
{“level”: “INFO”, “message”: “message”, “msecs”: 16.5140209197998, “name”: “name”, “time”: “2015-12-19 15:51:32”}






Handlers
pygogo has several builtin handlers and also supports any instance from the
logging.handlers module.

Examples

builtin stdout handler in python
import pygogo as gogo

hdlr = gogo.handlers.stdout_hdlr()
gogo.Gogo('stdout', low_hdlr=hdlr).logger.debug('message')

# Prints 'message' to `stdout`


logging.StreamHandler instance in python
import logging
import sys
import pygogo as gogo

hdlr = logging.StreamHandler(sys.stdout)
gogo.Gogo('stdout', low_hdlr=hdlr).get_logger('custom').debug('message')

# Prints 'message' to `stdout`


builtin CSV format via CLI
gogo --low-hdlr=stdout 'message'

# Prints 'message' to `stdout`



Summary
The following table can help make sense of the different builtin handlers:


name
description



buffered
Holds log in memory until it reaches its
capacity, or it logs a message with a
level at or above the flush level

email
Emails log to a given email address

file
Writes log to a given filename

fileobj
Writes log to a given file-like object

socket
Writes log to a given network socket

stderr
Writes log to standard error

stdout
Writes log to standard output

syslog
Writes log to syslog

webhook
POSTs log to a url






Scripts
pygogo comes with a built in task manager manage.py

Setup
pip install -r dev-requirements.txt


Examples
Run python linter and nose tests
manage lint
manage test



Contributing
Please mimic the coding style/conventions used in this repo.
If you add new classes or functions, please add the appropriate doc blocks with
examples. Also, make sure the python linter and nose tests pass.
Please see the contributing doc for more details.


License
pygogo is distributed under the MIT License.



Changelog

%%version%% (unreleased)

New

Add changelog.
Add quick logger instantiation.



Bugfixes

Don’t parse args unless running as script.
Fix CLI usage text.
Fix examples.
Fix packaging scripts.
Update docs, fix requirements, and remove sphinx.




v0.8.13 (2016-01-01)
Bugfixes

Fix new year bug.



v0.8.10 (2015-12-30)
Bugfixes

Fix capitalization.
Fix optional dependency parsing.
Fix spacing and remove unneeded marker.



v0.8.9 (2015-12-30)
Bugfixes

Fix conditional dependency configuration.
Fix requirements.



v0.8.8 (2015-12-29)
Bugfixes

Fix project name.



v0.8.7 (2015-12-29)
Bugfixes

Add pygogo to script path.
Add pygogo to test path.



v0.8.6 (2015-12-29)
Bugfixes

Fix doccheck errors.



v0.8.5 (2015-12-29)
Bugfixes

Add missing helper script.



v0.8.4 (2015-12-29)
Bugfixes

Fix setup.py (again!)



v0.8.3 (2015-12-29)
Bugfixes

Fix setup.py.



v0.8.2 (2015-12-29)
Bugfixes

Fix travis.



v0.8.1 (2015-12-29)
Bugfixes

Fix tox config and tests.
Change helper script name.
Fix spacing.
Fix makefile error.
Only clean once.



v0.8.0 (2015-12-25)
Bugfixes

Fix sphinx.
Fix tox.
Fix lint errors.
Fix tests.



v0.7.0 (2015-12-23)
Bugfixes

Fix lint error.



v0.6.3 (2015-12-22)
Bugfixes

Fix pylint errors.
Fix pylint and make check optional.
Don’t overwrite fmtrs argument.



v0.5.0 (2015-12-20)
Bugfixes

Fix duplicate handler/filter bug.
Fix tests.
Fix assertion arg orders.



v0.4.0 (2015-12-19)

New

Add BOM formatter.



Bugfixes

Fix spelling and spacing.
Fix lint errors.
Fix example.
Fix lint errors and add msecs to formatter.
Remove ‘ascitime’ from StructuredFormatter.
Use port if given.
Fix docblocks.




v0.2.2 (2015-12-07)
Bugfixes

Fix typo.