Local Gateway Mode

[scartill]

No description provided.

[scartill]

Code Review Summary

Decision: REQUEST CHANGES (2 High, 2 Medium findings)

Full report saved to docs/codereviews/pr-30-review.md

Required Fixes:

1. Path parameter corruption on non-greedy routes (local_server.py): Restrict path_params.pop('path') to greedy catch-all routes (if route.is_greedy and 'path' in path_params:).
2. Unhandled OSError on Windows (local_cli.py): Wrap Path(value).exists() in ry...except (OSError, ValueError) when parsing --auth-context / --event inline JSON strings.
3. Cross-platform module cleanup (local_handler.py): Resolve module path with Path(mod_file).resolve() before checking startswith.
4. Lock contention on request body (local_server.py): Move �wait build_event(...) and
   equest.body() reading before �sync with _invocation_lock:.

[scartill]

🚀 PR Review (Pass 2): Local Gateway Mode

Summary

This second review pass approves PR #30 (Local Gateway Mode). All 4 High/Medium issues identified in Pass 1 have been completely resolved, validated against test suites, and verified on Windows environment.

The "Why" & "What"

Provides local Lambda execution capability (easysam local . and easysam local invoke <function>) powered by FastAPI, enabling developers to locally run, test, and debug EasySAM applications with full API Gateway v1/v2 event mapping, per-function environment variable isolation, and function URL simulation without requiring cloud deployments.

Key Changes & Improvements in Pass 2

• Path Parameter Routing Fix: Non-greedy routes with {path} parameters retain exact parameter names, while greedy catch-all routes correctly translate {path} to proxy.
• Cross-Platform Resilience: Trapped OSError on Windows when parsing inline --auth-context or --event JSON strings.
• Robust Module Sandbox: Standardized module path matching using Path(...).resolve() to ensure clean unloading of local modules across handler invocations.
• Concurrency Optimization: Moved network request body reads outside global invocation lock (_invocation_lock) to prevent slow upload streams from blocking concurrent requests.
• Code Quality: Resolved all ruff linter issues (0 warnings/errors remaining).

QA & Testing Verification

• Unit & Integration Suite: 74/74 tests passing (uv run pytest tests/).
• Linter: 0 issues (uv run ruff check).

Recommended Next Action

✅ Approved for Merge into main.

[scartill]

Local Gateway & Execution Mode (Pass 3 Final Review)

The "Why" & "What"

EasySAM now supports comprehensive local development and offline testing of SAM applications without needing AWS deployment. This PR adds a local HTTP gateway server (�asysam local .) that mocks AWS API Gateway (v1 REST API and v2 HTTP API formats) and dynamic Lambda function execution (�asysam local invoke ) with isolated module loading, CORS support, custom event synthesis, and AWS credentials/region injection.

Key User-Facing & Behavioral Changes

• Positional Directory Syntax: Simplified CLI invocation to �asysam local [DIRECTORY] (defaults to current directory .).
• AWS Profile & Region Passthrough: Added support for --aws-profile and --target-region (and EASYSAM_AWS_PROFILE / EASYSAM_TARGET_REGION env vars) to automatically inject AWS_PROFILE, AWS_DEFAULT_REGION, and AWS_REGION into local handler environments.
• Bi-Modal API Gateway Simulation: Supports both v1 (REST API) and v2 (HTTP API) event structures with --event-format v1|v2.
• Authorizer Context Injection: Allows mock authorization context via --auth-context (JSON string or file path).
• Synchronous & Asynchronous Handler Execution: Handlers are executed with module isolation and restored environment variables.

Risk Assessment & Migration Notes

• Non-Breaking: Fully backwards compatible with existing EasySAM projects and templates.
• Local CORS: Local dev server enables wide-open CORS (*) for local frontend development ease; not used in production SAM deployments.
• Thread Safety: Process environment variable mutations during handler execution are synchronized with a module-level lock (_invocation_lock).

Testing Hints for QA

1. Local Server Execution: Run �asysam local --port 3000 --event-format v2 . in a project directory and send HTTP requests to test route dispatching and response formatting.
2. Direct Function Invocation: Execute �asysam local invoke my_function --event '{"key": "value"}' --aws-profile dev and verify environment variables (AWS_PROFILE, AWS_DEFAULT_REGION) are set correctly during execution.
3. Module Isolation: Trigger multiple requests across different functions in the same local server instance and verify shared dependencies (e.g. common.*) re-resolve cleanly without cross-function state leakage.