Eliot: Logging for Complex & Distributed Systems

Eliot is a Python logging system designed not only for simple applications but for complex applications as well, including distributed systems. Eliot supports simple structured messages but can also record a causal chain of actions happening within and across process boundaries: a logical trace of the system’s operation.

Structured, action-oriented logging is a great help when debugging problems. For example, here are the combined logs of a request originating from a client process being sent to a server. Notice how easy it is to figure out the cause of the problem, even though it’s opaque to the client:

process='client' task_uuid='40be6df2' task_level=[1] action_type='main'
    action_status='started'

process='client' task_uuid='40be6df2' task_level=[2, 1] action_type='http_request'
    action_status='started' x=5 y=0

process='server' task_uuid='40be6df2' task_level=[2, 2, 1] action_type='eliot:remote_task'
    action_status='started'

process='server' task_uuid='40be6df2' task_level=[2, 2, 2, 1] action_type='divide'
    action_status='started' x=5 y=0

process='server' task_uuid='40be6df2' task_level=[2, 2, 2, 2] action_type='divide'
    action_status='failed' exception='exceptions.ZeroDivisionError' reason='integer division or modulo by zero'

process='server' task_uuid='40be6df2' task_level=[2, 2, 3] action_type='eliot:remote_task'
    action_status='failed' exception='exceptions.ZeroDivisionError' reason='integer division or modulo by zero'

process='client' task_uuid='40be6df2' task_level=[2, 3] action_type='http_request'
   action_status='failed' exception='requests.exception.HTTPError' reason='500 Server Error: INTERNAL SERVER ERROR'

process='client' task_uuid='40be6df2' task_level=[3] action_type='main'
   action_status='failed' exception='requests.exception.HTTPError' reason='500 Server Error: INTERNAL SERVER ERROR'

Features:

Structured, typed log messages.
Ability to log actions, not just point-in-time information: log messages become a trace of program execution.
Logged actions can span processes and threads.
Excellent support for unit testing your code’s logging.
Emphasis on performance, including no blocking I/O in logging code path.
Optional Twisted support.
Designed for JSON output, usable by Logstash/Elasticsearch.
Supports CPython 2.7, 3.3, 3.4 and PyPy.
Eliot APIs provide both PEP 8 style (e.g. write_traceback()) and Twisted (e.g. writeTraceback()) method and function names. The only exceptions are pyunit-style assertions (e.g. assertContainsFields()) and Twisted-specific APIs since both use camelCase by default.

Eliot is released by ClusterHQ under the Apache 2.0 License.

To install:

$ pip install eliot

Downloads are available on PyPI.

Documentation can be found on Read The Docs.

Bugs and feature requests should be filed at the project Github page.

You can ask for help on IRC at the #eliot channel on irc.freenode.net.

Metadata

Release files for eliot 0.7.1

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for eliot 0.7.1
File	Size	Uploaded
eliot-0.7.1.tar.gz	90.8 kB	Apr 28, 2015	Details

Built distribution (wheel)

Table of built distributions (wheels) for eliot 0.7.1
File	Interpreter	ABI	Platform	Reset
eliot-0.7.1-py2.py3-none-any.whl 64.3 kB Apr 28, 2015	Python 3, Python 2	none	any	Details

Total release size: 155.0 kB

Release files / eliot-0.7.1.tar.gz

Download URL	eliot-0.7.1.tar.gz
Size	90.8 kB
Tags	Source
SHA-256 checksum How to use checksums	`0f53020f5a05f98e44db4b0ee0564334fd96a45a6dc03e7819a3d0a83cc25f17`
BLAKE2b-256 checksum How to use checksums	`d71730a0d472606df5fc251045eb65632c223e134152237d46cd492f8a31b373`
Upload date	Apr 28, 2015
Uploaded using Trusted Publishing? What is trusted publishing?	No

Release files / eliot-0.7.1-py2.py3-none-any.whl

Download URL	eliot-0.7.1-py2.py3-none-any.whl
Size	64.3 kB
Tags	Python 2 Python 3
SHA-256 checksum How to use checksums	`3e4515fa4b1710b62dad86813a781c39da076db8c74706c05f7a04ba42ca4b17`
BLAKE2b-256 checksum How to use checksums	`d33c7c6e42bdc7e77a5a0263a3b3c8359cd8b1adefd80a7b0c147ac9d772112b`
Upload date	Apr 28, 2015
Uploaded using Trusted Publishing? What is trusted publishing?	No