refactor: relocate extract_using_jq and jsonpath_modifier to appropriate modules

[jonpspri]

Summary

Refactored two utility functions from config.py to their appropriate usage locations, improving module cohesion and reducing the scope of the configuration module.

Functions relocated:

1. extract_using_jq: config.py → services/tool_service.py

   • Only used for processing REST tool responses with jq filters
   • Now located directly in the service that uses it

2. jsonpath_modifier: config.py → main.py

   • Used directly in API endpoints for dynamic JSONPath filtering
   • Now located in the main application module alongside its usage

Benefits

• Improved module cohesion: Functions now reside near their usage points
• Reduced config.py scope: Configuration module is now focused solely on settings management
• Cleaner imports: Removed unused imports from config.py (jq, jsonpath_ng, FastAPI HTTPException)
• Better type safety: Added proper type annotations to Settings.__init__ and Settings.log_summary

Changes

Code Movement

• Moved extract_using_jq with all docstring examples and error handling
• Moved jsonpath_modifier with complete implementation and docstrings
• Updated all import statements across the codebase

Test Coverage

• Migrated extract_using_jq tests from test_config.py → test_tool_service.py
• Migrated jsonpath_modifier tests from test_config.py → test_main.py
• Updated fuzz test imports in fuzz_jsonpath.py and test_jsonpath_fuzz.py
• Updated mock patches in tool service tests to reflect new import paths

Additional Improvements

• Re-enabled Black formatter in pre-commit config
• Added type hints: __init__(self, **kwargs: Any) -> None
• Added type hints: log_summary(self) -> None

Testing

All existing tests pass with updated imports:

• Unit tests for both functions maintained
• Fuzz tests updated and functional
• Mock patches in integration tests updated

Test Plan

• Run unit tests: pytest tests/unit/mcpgateway/test_config.py
• Run unit tests: pytest tests/unit/mcpgateway/test_main.py
• Run unit tests: pytest tests/unit/mcpgateway/services/test_tool_service.py
• Run fuzz tests: pytest tests/fuzz/test_jsonpath_fuzz.py
• Verify no import errors
• Run full test suite

[Copilot]

Pull Request Overview

This PR refactors two utility functions (extract_using_jq and jsonpath_modifier) from the config.py module to their actual usage locations, improving code organization and module cohesion. The functions are moved to services/tool_service.py and main.py respectively, where they are actually used.

Key Changes:

• Relocated extract_using_jq from config.py to services/tool_service.py where it processes REST tool responses
• Relocated jsonpath_modifier from config.py to main.py where it's used in API endpoints
• Updated all import statements and test mocks across the codebase to reflect the new locations

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
mcpgateway/config.py	Removed extract_using_jq and jsonpath_modifier functions, cleaned up unused imports, added type hints to __init__ and log_summary
mcpgateway/main.py	Added jsonpath_modifier function with complete implementation and necessary imports
mcpgateway/services/tool_service.py	Added extract_using_jq function with complete implementation and jq import
tests/unit/mcpgateway/test_config.py	Removed tests for relocated functions
tests/unit/mcpgateway/test_main.py	Added tests for jsonpath_modifier with new import
tests/unit/mcpgateway/services/test_tool_service.py	Added tests for extract_using_jq and updated mock patches
tests/fuzz/test_jsonpath_fuzz.py	Updated import path for jsonpath_modifier
tests/fuzz/fuzzers/fuzz_jsonpath.py	Updated import path for jsonpath_modifier
.pre-commit-config.yaml	Re-enabled Black formatter

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[Copilot]

[nitpick] The blank line at 695 appears to be an unnecessary addition that doesn't improve readability. Consider removing it to maintain consistency with the original code style.

Suggested change

[jonpspri]

Leaving this in draft until after #1331 is committed -- that should resolve the last failing test.