jsonformatter is a formatter for python easily output custom json log, e.g. output LogStash needed log

MyColorfulDays Last update: Jul 21, 2022

jsonformatter -- for python log json

jsonformatter -- for python log json

jsonformatter is a formatter for python output json log, e.g. output LogStash needed log.

Easily custom(add/replace) LogRecord attribute, e.g. in Flask web project, add username attribute to LogRecord for auto output username.

Python 2.7 and python 3 are supported from version 0.2.X, if you are using a version lower than 0.2.X, Only python 3 is supported.

Installation

jsonformatter is available on PyPI.Use pip to install:

$ pip install jsonformatter

or:

$ git clone https://github.com/MyColorfulDays/jsonformatter.git$ cd jsonformatter$ python setup.py install

Basic Usage

Case 1. Initial root logger like `logging.basicConfig`

import loggingfrom jsonformatter import basicConfig# default keyword parameter `format`: """{"levelname": "levelname", "name": "name", "message": "message"}"""basicConfig(level=logging.INFO)logging.info('hello, jsonformatter')

output:

{"levelname": "INFO", "name": "root", "message": "hello, jsonformatter"}

Case 2. Complete config in python code

import loggingfrom jsonformatter import JsonFormatter# `format` can be `json`, `OrderedDict`, `dict`.# If `format` is `dict` and python version < 3.7.0, the output order is sorted keys, otherwise will same as defined order.# key: string, can be whatever you like.# value: `LogRecord` attribute name.STRING_FORMAT = '''{    "Name":            "name",    "Levelno":         "levelno",    "Levelname":       "levelname",    "Pathname":        "pathname",    "Filename":        "filename",    "Module":          "module",    "Lineno":          "lineno",    "FuncName":        "funcName",    "Created":         "created",    "Asctime":         "asctime",    "Msecs":           "msecs",    "RelativeCreated": "relativeCreated",    "Thread":          "thread",    "ThreadName":      "threadName",    "Process":         "process",    "Message":         "message"}'''root = logging.getLogger()root.setLevel(logging.INFO)formatter = JsonFormatter(STRING_FORMAT)sh = logging.StreamHandler()sh.setFormatter(formatter)sh.setLevel(logging.INFO)root.addHandler(sh)root.info("test %s format", 'string')

output:

{"Name": "root", "Levelno": 20, "Levelname": "INFO", "Pathname": "test.py", "Filename": "test.py", "Module": "test", "Lineno": 75, "FuncName": "test_string_format", "Created": 1588185267.3198836, "Asctime": "2020-04-30 02:34:27,319", "Msecs": 319.8835849761963, "RelativeCreated": 88.2880687713623, "Thread": 16468, "ThreadName": "MainThread", "Process": 16828, "Message": "test string format"}

Case 3. Use config file

config file:

$ cat logger_config.ini[loggers]keys=root[logger_root]level=INFOhandlers=infohandler###############################################[handlers]keys=infohandler[handler_infohandler]class=StreamHandlerlevel=INFOformatter=form01args=(sys.stdout,)###############################################[formatters]keys=form01[formatter_form01]class=jsonformatter.JsonFormatterformat={"name": "name","levelno": "levelno","levelname": "levelname","pathname": "pathname","filename": "filename","module": "module","lineno": "lineno","funcName": "funcName","created": "created","asctime": "asctime","msecs": "msecs","relativeCreated": "relativeCreated","thread": "thread","threadName": "threadName","process": "process","message": "message"}

python code:

import loggingimport osfrom logging.config import fileConfigfileConfig(os.path.join(os.path.dirname(__file__), 'logger_config.ini'))root = logging.getLogger('root')root.info('test file config')

output:

{"name": "root", "levelno": 20, "levelname": "INFO", "pathname": "test.py", "filename": "test.py", "module": "test", "lineno": 315, "funcName": "test_file_config", "created": 1588185267.3020294, "asctime": "2020-04-30 02:34:27", "msecs": 302.0293712615967, "relativeCreated": 70.4338550567627, "thread": 16468, "threadName": "MainThread", "process": 16828, "message": "test file config"}

Case 4. In `Flask` project, add `LogRecord` attribute for auto output

flask_demo.py

import datetimeimport jsonimport loggingimport randomfrom collections import OrderedDictfrom jsonformatter import JsonFormatterfrom flask import Flask, has_request_context, request, sessionfrom flask.logging import default_handlerapp = Flask(__name__)# the key will add/replace `LogRecord` attribute.# the value must be `callable` type and not support positional paramters, the returned value will be as the `LogRecord` attribute value.RECORD_CUSTOM_ATTRS = {    # no parameters    'url': lambda: request.url if has_request_context() else None,    'username': lambda: session['username'] if has_request_context() and ('username' in session) else None,    # Arbitrary keywords parameters    'status': lambda **record_attrs: 'failed' if record_attrs['levelname'] in ['ERROR', 'CRITICAL'] else 'success'}RECORD_CUSTOM_FORMAT = OrderedDict([    # custom record attributes start    ("Url", "url"),    ("Username", "username"),    ("Status", "status"),    # custom record attributes end    ("Name", "name"),    ("Levelno", "levelno"),    ("Levelname", "levelname"),    ("Pathname", "pathname"),    ("Filename", "filename"),    ("Module", "module"),    ("Lineno", "lineno"),    ("FuncName", "funcName"),    ("Created", "created"),    ("Asctime", "asctime"),    ("Msecs", "msecs"),    ("RelativeCreated", "relativeCreated"),    ("Thread", "thread"),    ("ThreadName", "threadName"),    ("Process", "process"),    ("Message", "message")])formatter = JsonFormatter(    RECORD_CUSTOM_FORMAT,    record_custom_attrs=RECORD_CUSTOM_ATTRS)default_handler.setFormatter(formatter)app.logger.warning('hello, jsonformatter')

output:

{"Url": null, "Username": null, "Status": "success", "Name": "flask_demo", "Levelno": 30, "Levelname": "WARNING", "Pathname": "flask_demo.py", "Filename": "flask_demo.py", "Module": "flask_demo", "Lineno": 54, "FuncName": "<module>", "Created": 1595781463.3557186, "Asctime": "2020-07-27 00:37:43,355", "Msecs": 355.71861267089844, "RelativeCreated": 858.7081432342529, "Thread": 15584, "ThreadName": "MainThread", "Process": 17560, "Message": "hello, jsonformatter"}

Case 5. In `Django` project, config `LOGGING`

settings.py

LOGGING = {    'version': 1,    'disable_existing_loggers': False,    'formatters': {        'standard': {            'class': 'jsonformatter.JsonFormatter',            'format': OrderedDict([                ("Name", "name"),                ("Levelno", "levelno"),                ("Levelname", "levelname"),                ("Pathname", "pathname"),                ("Filename", "filename"),                ("Module", "module"),                ("Lineno", "lineno"),                ("FuncName", "funcName"),                ("Created", "created"),                ("Asctime", "asctime"),                ("Msecs", "msecs"),                ("RelativeCreated", "relativeCreated"),                ("Thread", "thread"),                ("ThreadName", "threadName"),                ("Process", "process"),                ("Message", "message")            ])        },    },    'handlers': {        'console': {            'level': 'INFO',            'formatter': 'standard',            'class': 'logging.StreamHandler',        },    },    'loggers': {        'django': {            'handlers': ['console'],            'level': 'INFO',            'propagate': False        },    }}

More Usage

Case 1. Mix `extra` to output

import loggingfrom jsonformatter import JsonFormatterroot = logging.getLogger()root.setLevel(logging.INFO)sh = logging.StreamHandler()formatter = JsonFormatter(    ensure_ascii=False,     mix_extra=True,    mix_extra_position='tail' # optional: head, mix)sh.setFormatter(formatter)sh.setLevel(logging.INFO)root.addHandler(sh)root.info(    'test mix extra in fmt',    extra={        'extra1': 'extra content 1',        'extra2': 'extra content 2'    })root.info(    'test mix extra in fmt',    extra={        'extra3': 'extra content 3',        'extra4': 'extra content 4'    })

output:

{"levelname": "INFO", "name": "root", "message": "test mix extra in fmt", "extra1": "extra content 1", "extra2": "extra content 2"}{"levelname": "INFO", "name": "root", "message": "test mix extra in fmt", "extra3": "extra content 3", "extra4": "extra content 4"}

Case 2. Output multiple attributes in one key

import loggingfrom jsonformatter import JsonFormatterMULTI_ATTRIBUTES_FORMAT = '''{    "multi attributes in one key": "%(name)s - %(levelno)s - %(levelname)s - %(pathname)s - %(filename)s - %(module)s - %(lineno)d - %(funcName)s - %(created)f - %(asctime)s - %(msecs)d - %(relativeCreated)d - %(thread)d - %(threadName)s - %(process)d - %(message)s"}'''root = logging.getLogger()root.setLevel(logging.INFO)formatter = JsonFormatter(MULTI_ATTRIBUTES_FORMAT)sh = logging.StreamHandler()sh.setFormatter(formatter)sh.setLevel(logging.INFO)root.addHandler(sh)root.info('test multi attributes in one key')

Case 3. Support `json.dumps` all optional parameters

import loggingfrom jsonformatter import JsonFormatterSTRING_FORMAT = '''{    "Name":            "name",    "Levelno":         "levelno",    "Levelname":       "levelname",    "Pathname":        "pathname",    "Filename":        "filename",    "Module":          "module",    "Lineno":          "lineno",    "FuncName":        "funcName",    "Created":         "created",    "Asctime":         "asctime",    "Msecs":           "msecs",    "RelativeCreated": "relativeCreated",    "Thread":          "thread",    "ThreadName":      "threadName",    "Process":         "process",    "Message":         "message"}'''root = logging.getLogger()root.setLevel(logging.INFO)formatter = JsonFormatter(STRING_FORMAT, indent=4, ensure_ascii=False)sh = logging.StreamHandler()sh.setFormatter(formatter)sh.setLevel(logging.INFO)root.addHandler(sh)root.info('test json optional paramter: 中文')

Case 4. Solve cumtom `LogRecord` attribute is not `JSON serializable`

import datetimeimport jsonimport loggingimport randomfrom collections import OrderedDictfrom jsonformatter import JsonFormatter# the key will add/replace `LogRecord` attribute.# the value must be `callable` type and not support positional paramters, the returned value will be as the `LogRecord` attribute value.RECORD_CUSTOM_ATTRS = {    # `datetime.datetime` type is not JSON serializable.    # solve it in three ways, choose which you like.    # 1. use `LogRecord` attribute `Format`: %(asctme)s.    # 2. use `json.dumps` optional parameter `default`.    # 3. use `json.dumps` optional parameter `cls`.    'asctime': lambda: datetime.datetime.today(),    'user id': lambda: str(random.random())[2:10]}RECORD_CUSTOM_FORMAT = OrderedDict([    ("User id",         "user id"),  # new custom attrs    ("Name",            "name"),    ("Levelno",         "levelno"),    ("Levelname",       "levelname"),    ("Pathname",        "pathname"),    ("Filename",        "filename"),    ("Module",          "module"),    ("Lineno",          "lineno"),    ("FuncName",        "funcName"),    ("Created",         "created"),    ("Asctime",         "%(asctime)s"),  # use `LogRecord` attribute `Format` to find matched key from RECORD_CUSTOM_ATTRS and call it value.    ("Msecs",           "msecs"),    ("RelativeCreated", "relativeCreated"),    ("Thread",          "thread"),    ("ThreadName",      "threadName"),    ("Process",         "process"),    ("Message",         "message")])# use `json.dumps` optional parameter `default`def DEFAULT_SOLUTION(o):    if not isinstance(o, (str, int, float, bool, type(None))):        return str(o)    else:        return o# use `json.dumps` optional parameter `cls`class CLS_SOLUTION(json.JSONEncoder):    def default(self, o):        if isinstance(o, datetime.datetime):            return o.isoformat()        return json.JSONEncoder.default(self, o)root = logging.getLogger()root.setLevel(logging.INFO)formatter = JsonFormatter(RECORD_CUSTOM_FORMAT, record_custom_attrs=RECORD_CUSTOM_ATTRS, default=DEFAULT_SOLUTION, cls=CLS_SOLUTION)sh = logging.StreamHandler()sh.setFormatter(formatter)sh.setLevel(logging.INFO)root.addHandler(sh)root.info('record custom attrs')

LogRecord Attributes

Offical url: https://docs.python.org/3/library/logging.html#logrecord-attributes

Attribute name	Format	Description
args	You shouldn’t need to format this yourself.	The tuple of arguments merged into msg to produce message, or a dict whose values are used for the merge (when there is only one argument, and it is a dictionary).
asctime	%(asctime)s	Human-readable time when the LogRecord was created. By default this is of the form ‘2003-07-08 16:49:45,896’ (the numbers after the comma are millisecond portion of the time).
created	%(created)f	Time when the LogRecord was created (as returned by time.time()).
exc_info	You shouldn’t need to format this yourself.	Exception tuple (à la sys.exc_info) or, if no exception has occurred, None.
filename	%(filename)s	Filename portion of pathname.
funcName	%(funcName)s	Name of function containing the logging call.
levelname	%(levelname)s	Text logging level for the message ('DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL').
levelno	%(levelno)s	Numeric logging level for the message (DEBUG, INFO, WARNING, ERROR, CRITICAL).
lineno	%(lineno)d	Source line number where the logging call was issued (if available).
message	%(message)s	The logged message, computed as msg % args. This is set when Formatter.format() is invoked.
module	%(module)s	Module (name portion of filename).
msecs	%(msecs)d	Millisecond portion of the time when the LogRecord was created.
msg	You shouldn’t need to format this yourself.	The format string passed in the original logging call. Merged with args to produce message, or an arbitrary object (see Using arbitrary objects as messages).
name	%(name)s	Name of the logger used to log the call.
pathname	%(pathname)s	Full pathname of the source file where the logging call was issued (if available).
process	%(process)d	Process ID (if available).
processName	%(processName)s	Process name (if available).
relativeCreated	%(relativeCreated)d	Time in milliseconds when the LogRecord was created, relative to the time the logging module was loaded.
stack_info	You shouldn’t need to format this yourself.	Stack frame information (where available) from the bottom of the stack in the current thread, up to and including the stack frame of the logging call which resulted in the creation of this record.
thread	%(thread)d	Thread ID (if available).
threadName	%(threadName)s	Thread name (if available).