# Phase 2 Plan 1: API Client Core Infrastructure Summary

**Core API client infrastructure complete with exception hierarchy, retry logic, and connection pooling**

## Accomplishments

- Installed tenacity 9.1.2 for sophisticated retry strategies with exponential backoff
- Created custom exception hierarchy with 5 specific exceptions mapped to HTTP status codes (401, 404, 429, 400, 5xx)
- Implemented APIClient hub class with httpx.Client for connection pooling, context manager pattern, and automatic retry logic
- Achieved 100% test coverage for exception handling and client core functionality (24 tests total)
- All quality gates passing: pytest, ruff, mypy with strict type checking

## Files Created/Modified

- `src/n8n_cli/client/__init__.py` - Public API exports for client module
- `src/n8n_cli/client/exceptions.py` - Custom exception hierarchy (N8NAPIError base + 5 specific exceptions) with handle_response() helper
- `src/n8n_cli/client/core.py` - APIClient hub class with connection pooling, retry decorator, context manager, and HTTP method wrappers
- `tests/test_exceptions.py` - Comprehensive tests for exception inheritance and status code mapping (11 tests)
- `tests/test_client_core.py` - Tests for client initialization, context manager, request methods, error handling, retry logic, and connection pooling (13 tests)
- `pyproject.toml` - Added tenacity>=9.0 dependency
- `uv.lock` - Locked tenacity 9.1.2

## Decisions Made

- Used typing.Self return type for __enter__ method (Python 3.12 feature) for better type safety
- Added type: ignore[no-any-return] comments for HTTP method wrappers due to tenacity decorator affecting return type inference
- Configured retry logic with exponential backoff: 2s, 4s, 8s (max 10s), max 3 attempts, retrying on httpx.HTTPError and ConnectionError
- Followed hub-and-spoke pattern from research - APIClient is the hub, resource modules will be spokes (Plan 2)
- Did NOT add resource properties (workflows, executions, etc.) to APIClient yet - deferred to Plan 2 as specified in plan

## Issues Encountered

- Pre-commit hooks auto-formatted imports (ruff) - re-staged files after auto-fix
- Mypy flagged no-any-return errors on HTTP method wrappers due to @retry decorator - resolved with type: ignore comments
- Test initially expected trailing slash on base_url ("https://api.n8n.cloud/") but httpx doesn't add it - corrected test assertion

## Next Step

Ready for 02-02-PLAN.md (Pydantic Response Models and Resources)
