mitmproxy is a production-grade, interactive HTTPS proxy that intercepts, inspects, modifies, and replays HTTP/1, HTTP/2, HTTP/3, WebSocket, TCP, UDP, DNS, and QUIC traffic. It supports multiple proxy modes (regular, transparent, reverse, upstream, SOCKS5, DNS, WireGuard, TUN, local) and provides three frontends: a console TUI (mitmproxy), a command-line dump tool (mitmdump), and a web UI (mitmweb). The architecture is event-driven with a sans-IO proxy layer design: protocol layers yield commands and events processed by an asyncio event loop. An extensive addon system allows users to extend functionality via lifecycle hooks, custom commands, and content views. The codebase is well-structured, heavily typed, and includes a comprehensive test suite with fuzzing and benchmarks. It is actively maintained with frequent releases and security patches.
mitmproxy2swagger is a CLI tool that automatically converts HTTP traffic captures from mitmproxy or browser HAR exports into OpenAPI 3.0 specifications. It enables reverse-engineering REST APIs by analyzing recorded traffic without manual inspection. The tool uses a two-pass workflow: the first pass identifies API paths and generates a template file with parameter placeholders; after the user edits the template to select endpoints, the second pass produces full endpoint descriptions with inferred request/response schemas. Architecturally, the tool is a single-purpose Python application organized into modular components: input readers (mitmproxy_capture_reader.py for binary flow files, har_capture_reader.py for HAR JSON), a core orchestration module (mitmproxy2swagger.py) that handles argument parsing, format auto-detection, and schema merging, and utility modules (swagger_util.py for OpenAPI schema generation, console_util.py for progress display). The tool supports multiple content types (JSON, msgpack, form-urlencoded) and can optionally include example data and headers in the output. Key entry points are the `mitmproxy2swagger` command with arguments for input file, output path, API prefix, and optional flags. External dependencies include mitmproxy for reading flow files, ruamel.yaml for YAML output, json-stream for streaming HAR parsing, and msgpack for msgpack support. The codebase is well-maintained with CI/CD, tests, Docker support, and pre-commit hooks.
Stoobly Agent is a monolithic Python application that acts as a man-in-the-middle HTTP(S) proxy for recording, mocking, replaying, and testing API interactions. Built on mitmproxy, it provides a comprehensive CLI (Click-based) for managing requests, scenarios, settings, and snapshots, as well as a scaffold system that generates full Docker Compose or local development workflows. The application supports four proxy modes (record, mock, test, develop) with configurable policies, rewrite rules, and lifecycle hooks that allow custom Python callbacks at various interception stages. It persists state to a local SQLite database via an ORM with migrations, and optionally integrates with a remote Stoobly cloud service for project and scenario management. The codebase exhibits a solid architecture with adapter patterns for converting between different HTTP representations (mitmproxy, Python requests, raw, ORM, Stoobly API), factory patterns for resource creation, and builder patterns for Docker Compose generation. However, it suffers from some technical drift (deprecated mitmproxy API usage, many lazy imports, global singletons) and the test suite includes flaky end-to-end tests that depend on external services. Overall, it is a well-crafted tool for API development and testing, with several reusable components, particularly the HTTP adapter system.