funnel-rules-engine 1.1.0

A simple, generic rules engine.

Rules Engine

A simple, generic rules engine. Inspired by Martin Fowler's 2009 blog post.

Installation

Install the package funnel_rules_engine version 1.1+ from PyPi. The recommended requirements.txt line is funnel_rules_engine~=1.1.

Current Functionality

Rule

A combination of a condition and an action, both of which are callables such as functions or lambdas.

Otherwise

Special case of Rule where the action always fires. Suitable as a catch-all last rule.

NoAction

Special case of Rule where None is returned if the condition is met. Useful for halting the execution of .run()

RulesEngine

A generic rules engine that accepts a list of Rules and some input to apply the rules to. The rules engine can either apply the first rule that matches (run) or all the rules that matches (run_all). In addition, rules can be evaluated and executed in parallel (run_all_in_parallel).

For more on rules engines, see Martin Fowler's blog post.

run

Only apply the first rule that matches and return its result. This is comparable to the behaviour of a structured switch statement or an arbitrary conditional statement.

run_all

Apply all rules that match. The result is returned as a list.

run_all_in_parallel

Evaluate and apply all rules in parallel. The result is returned as a list.