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Change Log🔗

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

4.0.0 - 2025-10-06🔗

Added🔗

  • Support DictConfigurator prefixes for rename_fields and static_fields. #45
    • Allows using values like ext://sys.stderr in fileConfig/dictConfig value fields.
  • Support comma seperated lists for Formatter fmt (style=",") e.g. "asctime,message,levelname" #15
    • Note that this style is specific to python-json-logger and thus care should be taken not to pass this format to other logging Formatter implementations.
  • Supports sequences of strings (e.g. lists and tuples) of field names for Formatter fmt. #16

Changed🔗

  • Rename pythonjsonlogger.core.LogRecord and log_record arguments to avoid confusion / overlapping with logging.LogRecord. #38
    • Affects arguments to pythonjsonlogger.core.BaseJsonFormatter (and any child classes).
      • serialize_log_record
      • add_fields
      • jsonify_log_record
      • process_log_record
    • Note: functions referring to log_record have not had their function name changed.

Removed🔗

  • Remove support for providing strings instead of objects when instantiating formatters. Instead use the DictConfigurator ext:// prefix format when using fileConfig/dictConfig. #47
    • Affects pythonjsonlogger.json.JsonFormatter: json_default, json_encoder, json_serializer.
    • Affects pythonjsonlogger.orjson.OrjsonFormatter: json_default.
    • Affects pythonjsonlogger.msgspec.MsgspecFormatter: json_default.

Thanks @rubensa

3.3.0 - 2025-03-06🔗

Added🔗

  • exc_info_as_array and stack_info_as_array options are added to pythonjsonlogger.core.BaseJsonFormatter allowing both to be encoded as list of lines instead of a single multi-line string. #35

Security🔗

  • Remove msgspec-python313-pre from dev dependencies preventing potential RCE. Details: GHSA-wmxh-pxcx-9w24

Thanks @1hakusai1 and @omnigodz

3.2.1 - 2024-12-16🔗

Fixed🔗

  • Import error on import pythonjsonlogger.jsonlogger #29

3.2.0 - 2024-12-11🔗

Changed🔗

  • pythonjsonlogger.[ORJSON,MSGSPEC]_AVAILABLE no longer imports the respective package when determining availability.
  • pythonjsonlogger.[orjson,msgspec] now throws a pythonjsonlogger.exception.MissingPackageError when required libraries are not available. These contain more information about what is missing whilst still being an ImportError.
  • defaults parameter is no longer ignored and now conforms to the standard library. Setting a defaults dictionary will add the specified keys if the those keys do not exist in a record or weren't passed by the extra parameter when logging a message.
  • typing_extensions is only installed on Python version < 3.10.
  • Support Python 3.13
    • msgspec has only been tested against pre-release versions.

Thanks @cjwatson and @bharel

3.1.0 - 2023-05-28🔗

This splits common funcitonality out to allow supporting other JSON encoders. Although this is a large refactor, backwards compatibility has been maintained.

Added🔗

  • pythonjsonlogger.core - more details below.
  • pythonjsonlogger.defaults module that provides many functions for handling unsupported types.
  • Orjson encoder support via pythonjsonlogger.orjson.OrjsonFormatter with the following additions:
    • bytes are URL safe base64 encoded.
    • Exceptions are "pretty printed" using the exception name and message e.g. "ValueError: bad value passed"
    • Enum values use their value, Enum classes now return all values as a list.
    • Tracebacks are supported
    • Classes (aka types) are support
    • Will fallback on __str__ if available, else __repr__ if available, else will use __could_not_encode__
  • MsgSpec encoder support via pythonjsonlogger.msgspec.MsgspecFormatter with the following additions:
    • Exceptions are "pretty printed" using the exception name and message e.g. "ValueError: bad value passed"
    • Enum classes now return all values as a list.
    • Tracebacks are supported
    • Classes (aka types) are support
    • Will fallback on __str__ if available, else __repr__ if available, else will use __could_not_encode__
    • Note: msgspec only supprts enum values of type int or str jcrist/msgspec#680

Changed🔗

  • pythonjsonlogger.jsonlogger has been moved to pythonjsonlogger.json with core functionality moved to pythonjsonlogger.core.
  • pythonjsonlogger.core.BaseJsonFormatter properly supports all logging.Formatter arguments:
    • fmt is unchanged.
    • datefmt is unchanged.
    • style can now support non-standard arguments by setting validate to False
    • validate allows non-standard style arguments or prevents calling validate on standard style arguments.
    • default is ignored.
  • pythonjsonlogger.json.JsonFormatter default encodings changed:
    • bytes are URL safe base64 encoded.
    • Exception formatting detected using BaseException instead of Exception. Now "pretty prints" the exception using the exception name and message e.g. "ValueError: bad value passed"
    • Dataclasses are now supported
    • Enum values now use their value, Enum classes now return all values as a list.
    • Will fallback on __str__ if available, else __repr__ if available, else will use __could_not_encode__
  • Renaming fields now preserves order (#7) and ignores missing fields (#6).
  • Documentation
    • Generated documentation using mkdocs is stored in docs/
    • Documentation within README.md has been moved to docs/index.md and docs/qucikstart.md.
    • CHANGELOG.md has been moved to docs/change-log.md
    • SECURITY.md has been moved and replaced with a symbolic link to docs/security.md.

Deprecated🔗

  • pythonjsonlogger.jsonlogger is now pythonjsonlogger.json
  • pythonjsonlogger.jsonlogger.RESERVED_ATTRS is now pythonjsonlogger.core.RESERVED_ATTRS.
  • pythonjsonlogger.jsonlogger.merge_record_extra is now pythonjsonlogger.core.merge_record_extra.

Removed🔗

  • Python 3.7 support dropped
  • pythonjsonlogger.jsonlogger.JsonFormatter._str_to_fn replaced with pythonjsonlogger.core.str_to_object.

3.0.1 - 2023-04-01🔗

Fixes🔗

  • Fix spelling of parameter json_serialiser -> json_serializer (#8) - @juliangilbey

3.0.0 - 2024-03-25🔗

Note: using new major version to seperate changes from this fork and the original (upstream). See #1 for details.

Changes🔗

  • Update supported Python versions - @nhairs
    • Drop 3.6
    • The following versions are supported and tested:
      • CPython 3.7-3.12 (ubuntu, windows, mac)
      • PyPy 3.7-3.10 (ubuntu, wundows, mac)
    • RESERVED_ATTRS is now a list and version dependent
  • Fix JsonFormatter.__init__ return type (None) - @nhairs
  • Moved to pyproject.toml - @nhairs
  • Update linting and testing - @nhairs
    • Split lint and test steps in GHA
    • Use validate-pyproject, black, pylint, mypy

2.0.7 - 2023-02-21🔗

Changed🔗

  • Fix inclusion of py.typed in pip packages - @sth
  • Added pytest support with test file rename. Migrated to assertEqual

2.0.6 - 2023-02-14🔗

Changed🔗

  • Parameter rename_fields in merge_record_extra is now optional - @afallou

2.0.5 - 2023-02-12🔗

Added🔗

  • Allow reserved attrs to be renamed - @henkhogan
  • Support added for Python 3.11
  • Now verifying builds in Pypy 3.9 as well
  • Type annotations are now in the package - @louis-jaris

Changed🔗

  • Fix rename_fields for exc_info - @guilhermeferrari
  • Cleaned up test file for PEP8 - @lopagela
  • Cleaned up old Python 2 artifacts - @louis-jaris
  • Dropped Python 3.5 support - @idomozes
  • Moved type check via tox into 3.11 run only
  • Added test run in Python3.6 (will keep for a little while longer, but it's EOL so upgrade)

2.0.4 - 2022-07-11🔗

Changed🔗

  • Fix too strict regex for percentage style logging - @aberres

2.0.3 - 2022-07-08🔗

Added🔗

  • Add PEP 561 marker/basic mypy configuration. - @bringhurst
  • Workaround logging.LogRecord.msg type of string. - @bringhurst

Changed🔗

  • Changed a link archive of the reference page in case it's down. - @ahonnecke
  • Removed unnecessary try-except around OrderedDict usage - @sozofaan
  • Update documentation link to json module + use https - @deronnax
  • Dropped 3.5 support. - @bringhurst

2.0.2 - 2021-07-27🔗

Added🔗

  • Officially supporting 3.9 - @felixonmars.
  • You can now add static fields to log objects - @cosimomeli.

Changed🔗

  • Dropped 3.4 support.
  • Dropped Travis CI for Github Actions.
  • Wheel should build for python 3 instead of just 3.4 now.

2.0.1 - 2020-10-12🔗

Added🔗

  • Support Pypi long descripton - @ereli-cb

Changed🔗

  • You can now rename output fields - @schlitzered

2.0.0 - 2020-09-26🔗

Added🔗

  • New Changelog
  • Added timezone support to timestamps - @lalten
  • Refactored log record to function - @georgysavva
  • Add python 3.8 support - @tommilligan

Removed🔗

  • Support for Python 2.7
  • Debian directory

0.1.11 - 2019-03-29🔗

Added🔗

  • Support for Python 3.7

Changed🔗

  • 'stack_info' flag in logging calls is now respected in JsonFormatter by @ghShu