Django Dynamic Business Rules

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A Django centric event driven rules engine for extensible and configurable responses to changes to django models and triggers.

Documentation

The full documentation is at https://django-dynamic-business-rules.readthedocs.io.

Use Cases

  • Configure Rules for sending messages to users and edit them without deploying new code
  • Block spam users if they perform too many suspiscious activities during a certain time frame, allow non-programmer users to edit that time frame
  • Trigger a required password reset if a configurable set of suspiscious behaviors are encountered

Key Ideas

The goal of this project is to allow non-technical users to be able to configure behaviors of the system, similar to a commercial tool like IFFT or Zapier. Non-developer end users of this tool are not required to be programmers but they will need to be at least somewhat technical in their understanding of the system so for the remainder of the document will will refer to them as “analysts”.

Quickstart

Install Django Dynamic Business Rules:

pip install django-dynamic-business-rules

Add it to your INSTALLED_APPS:

INSTALLED_APPS = (
    ...
    'dynamic_business_rules.apps.DynamicBusinessRulesConfig',
    ...
)

Add Django Dynamic Business Rules’s URL patterns:

from dynamic_business_rules import urls as dynamic_business_rules_urls


urlpatterns = [
    ...
    url(r'^admin/dynamic-rules/', include(dynamic_business_rules_urls)),
    ...
]

Create a Variable class

In one of your Django apps create a variable class in a file named dynamic_rule_variables.py (this name must be used so we can introspect apps looking for implementations of variable classes)

The Variable object translates a Django signal into a set of values that non-technical users can use when creating conditional business rules. For an example Variable object see example/dynamic_rule_variables.py you’ll notice that the variable object doesn’t inherit from any object, it’s constructor receives a django signal as kwargs and then its properties evaluate the properties of that signal (in the case of the example the post_save signal’s instance is a key value).

Create an Action class

In one of your Django apps create an action class in a file named dynamic_rule_actions.py (this name must be used so we can introspect apps looking for implementations of action classes)

The action object provides methods that rule sets can “fire” if all their conditions evaluate to true.

Screenshots of Admin

Creating a New Rule

docs/img/admin_basic_rule_setup.png

Adding Conditions To Evaluate

docs/img/admin_condition_sets.png

Features

  • Allows users to implement and extend their own Variable and Action classes in a flexible way that allows you to build a business rules engine that fits the needs of your project.

Running Tests

Does the code actually work?

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

Credits

Tools used in rendering this package: