Runtime rules engine

[joshua-koehler]

Support complex runtime rules in local-evaluation - no network calls required!

GitHub Copilot Summary

This pull request introduces a new runtime rules engine for feature flag evaluation using JSON Logic, and updates the test suite to cover a wide range of rule scenarios. The main benefit is that feature flag rollouts can now be controlled by expressive, declarative rules, improving flexibility and maintainability. Legacy runtime evaluation logic is preserved for backward compatibility, but is ignored when new-style rules are present.

Feature flag evaluation logic:

• Added dependency on json_logic and implemented _is_runtime_rules_engine_satisfied, which evaluates rollout rules using JSON Logic when runtime_evaluation_rule is present, falling back to legacy logic otherwise. [1] [2]
• Updated rollout assignment logic to prefer runtime_evaluation_rule over legacy runtime_evaluation_definition, ensuring backward compatibility but prioritizing new rules.

Test suite enhancements:

• Refactored test flag creation and test context usage for consistency (TEST_FLAG_KEY, USER_CONTEXT), and added helper for user context with custom properties. [1] [2]
• Added comprehensive tests for JSON Logic rules, including equality, containment, multi-value, logical AND, comparison, and precedence over legacy definitions.
• Ensured legacy runtime evaluation logic is correctly tested and only used when no new-style rule is present.

General test improvements:

• Updated all test usages to use the new constants and helpers for improved readability and maintainability. [1] [2] [3] [4] [5] [6] [7] [8] [9]

[codecov]

Codecov Report

❌ Patch coverage is 97.34513% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 94.28%. Comparing base (71c22a2) to head (f315638).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
mixpanel/flags/local_feature_flags.py	86.04%	2 Missing and 4 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #148      +/-   ##
==========================================
+ Coverage   93.81%   94.28%   +0.46%     
==========================================
  Files           9        9              
  Lines        1375     1557     +182     
  Branches       91      101      +10     
==========================================
+ Hits         1290     1468     +178     
- Misses         52       54       +2     
- Partials       33       35       +2     

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[Copilot]

Pull Request Overview

This PR adds support for a runtime rules engine in local feature flag evaluation, enabling complex rule evaluation without network calls. The implementation uses the json-logic library to evaluate JSON-based rules against user properties.

• Adds json-logic dependency for evaluating complex runtime rules
• Introduces runtime_evaluation_rule field to support JSON-based rule definitions
• Maintains backward compatibility with legacy runtime_evaluation_definition

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
pyproject.toml	Adds json-logic>=0.7.0a0 dependency for rule evaluation
mixpanel/flags/types.py	Adds runtime_evaluation_rule field to Rollout model to support JSON-based rules
mixpanel/flags/local_feature_flags.py	Implements _is_runtime_rules_engine_satisfied() method to evaluate JSON logic rules, with fallback to legacy evaluation
mixpanel/flags/test_local_feature_flags.py	Adds comprehensive test coverage for JSON logic rules including equality, contains, multi-value, AND operations, comparisons, and legacy compatibility

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Pull Request Overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 5 comments.

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Pull Request Overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated no new comments.

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[msiebert]

[jaredmixpanel]

LGTM