============================= Django Eraserhead

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Provide hints to optimize database usage by deferring unused fields

.. image:: https://github.com/dizballanze/django-eraserhead/raw/master/eraserhead.jpg

WARNING use this package only in dev environment!

Documentation

Requirements

• Django 1.9+
• Python 2.7, 3.4+

Quickstart

Install Django Eraserhead::

pip install django-eraserhead

Add it to your INSTALLED_APPS:

.. code-block:: python

INSTALLED_APPS = (
    ...
    'eraserhead.apps.EraserheadConfig',
    ...
)

ERASERHEAD_ENABLED = True
ERASERHEAD_TRACEBACK_BASE_PATH = BASE_DIR

Settings:

• ERASERHEAD_ENABLED - enable/disable Django Eraserhead
• ERASERHEAD_TRACEBACK_BASE_PATH - set base path to filter tracebacks. Set to None to display full traceback.

Features

.. image:: https://github.com/dizballanze/django-eraserhead/raw/master/screenshot.png

Django Eraserhead monitors:

• querysets/models fields usage (used and unused fields) with considering deferred fields
• count of instances created for each queryset
• corresponding model of each queryset
• traceback for each queryset to easily find corresponding code
• calculate memory consumption of unused fields

Based on fields usage Django Eraserhead suggests optimizations for each queryset.

TODO

• decorator and/or context processor for partial stats collecting
• detect deferred fields loading
• auto deferring fields based on usage
• display deferred fields

Running Tests

::

source <YOURVIRTUALENV>/bin/activate
(myenv) $ pip install tox
(myenv) $ tox

Credits

Tools used in rendering this package:

• Cookiecutter_
• cookiecutter-djangopackage_

.. _Cookiecutter: https://github.com/audreyr/cookiecutter .. _cookiecutter-djangopackage: https://github.com/pydanny/cookiecutter-djangopackage