responder/CHANGELOG.md

Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

v3.12.0 - 2026-06-12

Added

• Built-in metrics: API(metrics_route="/metrics") serves request counts and latency histograms in Prometheus text format, zero dependencies. Labels use route patterns (/users/{id}) so cardinality stays bounded; error responses are recorded with their real status codes
• Server-side sessions: API(session_backend=...) stores session data in a backend (MemorySessionBackend, RedisSessionBackend, or any object with get/set/delete) with only an opaque ID in the cookie — enabling revocation and unbounded session size. Handler code is unchanged
• Query-parameter validation: @api.route(..., params_model=Model) coerces and validates query strings with Pydantic (422 on failure), exposes the instance as req.state.validated_params, maps repeated keys to list fields, and documents the parameters in the OpenAPI spec
• resp.render(template, **context) — render a Jinja2 template as the HTML response body in one call

v3.11.0 - 2026-06-11

Added

• HTTP range requests: resp.file() and resp.stream_file() answer Range: bytes=... with 206 Partial Content (suffix and open-ended ranges, 416 for unsatisfiable, Accept-Ranges advertised) — enables video seeking and resumable downloads
• resp.download(path, filename=...) serves files as attachments with proper Content-Disposition (RFC 5987 encoding for non-ASCII names), streamed and resumable
• Request timeouts: API(request_timeout=seconds) answers overrunning handlers with 504 Gateway Timeout (content-negotiated); dependency teardowns still run

Performance

• Route resolution is cached per (method, path) with invalidation on registration — ~10% faster dispatch at 81 routes, growing with route count

v3.10.0 - 2026-06-11

Added

• Trailing-slash redirects: requests that miss only by a trailing slash get a 307 to the canonical path, preserving method and query string. Disable with API(redirect_slashes=False)
• Request size limits: API(max_request_size=bytes) returns 413 for oversized bodies — fast-fails on Content-Length and enforces cumulatively for chunked/streamed uploads
• Automatic ETags: API(auto_etag=True) adds a content-hash ETag to GET responses with full 304 Not Modified handling; an explicit resp.etag always wins
• After-response background tasks: resp.background(func, *args) defers work until the client has the response (sync and async, ordered)
• resp.cache_control(...) helper for building Cache-Control headers

Fixed

• A 413 raised while reading the body during request_model validation is no longer swallowed into a 422

Changed

• Trailing-slash redirects are on by default (previously such requests were 404s)

v3.9.1 - 2026-06-11

Added

• Conditional request support: set resp.etag or resp.last_modified and matching If-None-Match/If-Modified-Since requests automatically get 304 Not Modified (RFC 7232 semantics: If-None-Match precedence, weak comparison, GET/HEAD only)
• Request body streaming: async for chunk in req.stream() iterates large uploads without buffering
• Pluggable rate-limiter backends: RateLimiter(backend=...) with the in-memory default plus a new RedisBackend for multi-process deployments
• Application state: api.state namespace, reachable from handlers via req.api.state
• req.api is now populated with the owning API instance (it was always None before)

Fixed

• API(static_dir=None) crashed on every route registration — the static fallback assertion now only applies when no endpoint is given
• The static-fallback error is a ValueError instead of a bare assert

Performance

• Request headers are parsed into the case-insensitive dict lazily, on first access (~5% faster dispatch on header-heavy requests that don't read headers)

v3.9.0 - 2026-06-11

Added

• Dependency injection for WebSocket handlers: declare path parameters and registered dependencies by name after the ws argument. Request-scoped providers taking a parameter receive the WebSocket; generator teardown runs when the handler finishes. Handlers that only take ws are unaffected
• OpenAPI 3.1 support (openapi="3.1.0")
• The OpenAPI schema endpoint now serves JSON when requested via Accept: application/json, or always when openapi_route ends in .json
• Path parameters are documented automatically in the OpenAPI spec from route patterns ({id:int} → required integer parameter)
• Built-in error responses (404, 405) are content-negotiated: JSON clients receive {"error": ...} bodies instead of plain text

Fixed

• OpenAPI paths no longer leak convertor patterns (/users/{id:int} is now emitted as the spec-compliant /users/{id})
• Registering a duplicate route now raises ValueError (previously an assert that disappears under python -O)
• Removed dead _exception_handlers bookkeeping in API.exception_handler

Changed

• mypy now passes with zero errors across the codebase (was 25); ruff is clean as well
• types-pyyaml added to the test extra

v3.8.0 - 2026-06-11

Added

• Handlers can return values: a dict/list sets resp.media, a str sets resp.text, and bytes set resp.content. Returning None keeps the mutate-resp behavior, so existing handlers are unaffected
• App-scoped dependencies: @api.dependency(scope="app") resolves the provider once on first use and caches it for the application's lifetime; generator teardown runs at shutdown
• Automatic OPTIONS responses with an Allow header for method-restricted routes
• HEAD requests are accepted wherever GET is
• set_cookie() gains a samesite parameter, defaulting to "lax"
• The validated request_model instance is now available to handlers as req.state.validated — no need to re-parse the body

Changed

• Requests to an existing path with an unsupported method now return 405 Method Not Allowed with an Allow header (previously 404)
• RouteGroup.before_request hooks are now scoped to the group's prefix (previously they silently applied to every route)

Performance

• View signature inspection for dependency injection is cached per function

v3.7.0 - 2026-06-11

Added

• Dependency injection for route handlers: register providers with @api.dependency() (or api.add_dependency(name, provider)) and declare them as view parameters by name. Supports sync/async functions and generators (code after yield runs as teardown once the response is sent). Providers accepting a parameter receive the current Request. Dependencies resolve at most once per request; path parameters take precedence.
• Per-route rate limiting via RateLimiter.limit decorator
• WebSocket before-request hooks can now reject connections: closing the socket in a hook short-circuits the route handler
• WebSocket before-request hooks may now be sync functions (run in the threadpool)
• Custom formats registered on api.formats now actually reach request parsing and response negotiation (previously each request got a fresh default format registry)

Fixed

• {value:float} path convertor matched garbage like 1a5 (unescaped regex dot) and crashed with a 500 — now correctly returns 404
• Literal characters in route paths are now regex-escaped, so /file.json no longer matches /fileXjson
• Unbounded memory growth in BackgroundQueue — completed futures are now pruned from results
• req.media("form") crashed with a TypeError when the request had no Content-Type header
• Content negotiation returned an empty body for Accept headers matching encode-incapable formats (e.g. multipart/form-data) — now falls through to JSON

Changed

• Request.url and Request.params are now computed once and cached
• Format registries are no longer rebuilt twice per request

v3.6.2 - 2026-04-12

Fixed

• GraphQL error responses now correctly return 400 status instead of always 200
• OpenAPI docs UI now respects custom openapi_route instead of hardcoding /schema.yml
• before_requests default type mismatch that could crash routes called outside the router
• Blocking synchronous file I/O in Response.stream_file() — now uses async I/O via anyio
• Memory leak in rate limiter (empty bucket keys never cleaned up)
• Race condition in rate limiter check() — added thread-safe locking
• WSGI fallback catching all TypeErrors instead of just call-signature mismatches
• Pydantic request/response model validation crashing on non-dict bodies
• Test assertions that could never fail (or True, < 500 patterns)
• CaseInsensitiveDict missing __delitem__, pop, and setdefault overrides
• assert used for input validation in OpenAPI extension (stripped by python -O)
• Potential XSS in GraphiQL template endpoint injection
• Dead or "" in media format detection logic

Changed

• DELETE requests now participate in Pydantic request body validation
• Simplified status code category check to use chained comparison

Removed

• Unused method parameter from load_target()
• Unused Node.js setup step from CI test workflow

v3.6.1 - 2026-04-12

Added

• Configurable GZip compression via gzip parameter on API() (defaults to True)

v3.6.0 - 2026-03-24

Added

• Built-in structured logging with per-request context (enable_logging=True)
  • api.log — always-available logger, enriched with request context when logging is enabled
  • Automatic access logging with timing: GET /path → 200 (1.2ms)
  • Request ID generation/forwarding via X-Request-ID header
  • contextvars-based request context (ID, method, path, client IP) on every log record
  • responder.ext.logging module: get_logger(), RequestContext, RequestContextFilter
• CLAUDE.md project guide and /release command
• Version number in docs sidebar

Changed

• Comprehensive documentation improvements across all pages
  • Deployment: health checks, Docker Compose, Caddy, Procfile, production checklist
  • API reference: usage examples for every class
  • Feature tour: Pydantic validation, content negotiation, structured logging sections
  • Tutorials: modernized SQLAlchemy to mapped_column(), fixed deprecated datetime.utcnow(), WebSocket WebSocketDisconnect handling, role-based auth, auth strategy guide
  • Testing: rate limiting and WSGI mount examples
  • Middleware: pure ASGI middleware example
  • Quickstart: links to all tutorials
  • Sandbox: full rewrite with project layout
• Docker example uses uv instead of pip
• Backlog updated: removed implemented features, replaced HTTP/2 server push with dependency injection

Removed

• uv.lock — this is a library, not an application

v3.5.0 - 2026-03-24

Added

• CI validation for Python 3.14, 3.14 free-threaded, and PyPy 3.11
• Marimo notebook mounting docs and example
• Type annotations for routes.py

Changed

• Replaced deprecated asyncio.iscoroutinefunction with inspect.iscoroutinefunction ahead of Python 3.16 removal
• Narrowed broad except Exception to specific exceptions in response model serialization and websocket chat example
• Improved GraphQL API interface with expanded test coverage
• Code formatting cleanup via pyproject-fmt and ruff
• Dropped Python 3.9 from CI

Fixed

• WSGI mount returning 400 when requesting the exact mount root path
• Werkzeug 3.1.7 compatibility for trusted host validation in tests
• future.result bare property access in background task test (now properly calls future.result())
• OpenAPI template packaging and static file serving
• RST title underline warning breaking docs CI

Removed

• Read the Docs configuration (docs hosted on GitHub Pages)

v3.4.0 - 2026-03-22

Changed

• Upgraded to Starlette 1.0
• Added comprehensive docstrings across the codebase
• Expanded API reference documentation

v3.3.0 - 2026-03-22

Added

• Full documentation rewrite: tutorials for REST APIs, SQLAlchemy, Flask migration
• Auth, WebSocket, middleware, and configuration guides
• Testing docs with prose, examples, and tips
• GitHub Pages deployment for docs

Changed

• Reworked homepage prose
• Rewrote CLI and API reference docs

v3.2.0 - 2026-03-22

Added

• Pydantic auto-validation: request_model validates input, returns 422 on failure
• Pydantic auto-serialization: response_model strips extra fields from responses
• Server-Sent Events: @resp.sse for real-time streaming
• resp.stream_file() for streaming large files without loading into memory
• @api.after_request() hooks
• api.group("/prefix") for route groups and API versioning
• api.graphql("/path", schema=schema) one-liner GraphQL setup
• api = responder.API(request_id=True) for automatic request ID generation
• Built-in rate limiter: RateLimiter(requests=100, period=60).install(api)
• MessagePack format support: await req.media("msgpack")
• req.is_json, req.path_params, req.client properties
• api.exception_handler() decorator for custom error handling
• Lifespan context manager support
• uuid and path route convertors
• PEP 561 py.typed marker
• Pydantic support for OpenAPI schema generation

Changed

• Dependencies flattened: pip install responder gets everything
• Core deps reduced to starlette + uvicorn
• TestClient lazy-loaded (no httpx import in production)
• Before-request hooks can short-circuit by setting status code
• Removed poethepoet task runner

Fixed

• Multipart parser losing headers when parts have multiple headers
• url_for() with typed route params ({id:int})
• resp.body encoding crash on bytes content
• GraphQL text query missing await
• Streaming responses not sending Content-Type headers
• Python 3.9 compatibility for union type syntax

v3.0.0 - 2026-03-22

Added

• Platform: Added support for Python 3.10 - Python 3.13
• CLI: responder run now also accepts a filesystem path on its <target> argument, enabling usage on single-file applications.
• CLI: responder run now also accepts URLs.

Changed

• Platform: Minimum Python version is now 3.9 (dropped 3.6, 3.7, 3.8)
• Dependencies: Dramatically reduced core dependency count (10 → 5)
  • Removed requests, requests-toolbelt, rfc3986, whitenoise
  • Moved apispec and marshmallow to openapi optional extra
  • Replaced rfc3986 with stdlib urllib.parse
  • Replaced requests-toolbelt multipart decoder with python-multipart
  • Replaced deprecated starlette.middleware.wsgi with a2wsgi
  • Switched from WhiteNoise to ServeStatic
• Dependencies: Pinned starlette[full]>=0.40 (was unpinned)
• GraphQL: Upgraded to graphene>=3 and graphql-core>=3.1 (from graphene<3 and graphql-server-core, which is unmaintained)
• GraphQL: Updated GraphiQL UI from 0.12.0 (2018) to 3.0.6 with React 18
• Extensions: All of CLI-, GraphQL-, and OpenAPI-Support modules are extensions now, found within the responder.ext module namespace.
• Packaging: Migrated from setup.py to declarative pyproject.toml

Removed

• Platform: Removed support for EOL Python 3.6, 3.7, 3.8
• Status codes: Removed deprecated resume_incomplete and resume aliases for HTTP 308 (marked for removal in 3.0)
• CLI: responder run --build ceased to exist

Fixed

• Routing: Fixed dispatching static_route=None on Windows
• uvicorn: --debug now maps to uvicorn's log_level = "debug"
• Tests: Fixed deprecated httpx TestClient usage

v2.0.5 - 2019-12-15

Added

• Update requirements to support python 3.8

v2.0.4 - 2019-11-19

Fixed

• Fix static app resolving

v2.0.3 - 2019-09-20

Fixed

• Fix template conflicts

v2.0.2 - 2019-09-20

Fixed

• Fix template conflicts

v2.0.1 - 2019-09-20

Fixed

• Fix template import

v2.0.0 - 2019-09-19

Changed

• Refactor Router and Schema

v1.3.2 - 2019-08-15

Added

• ASGI 3 support
• CI tests for python 3.8-dev
• Now requests have state a mapping object

Deprecated

• ASGI 2

v1.3.1 - 2019-04-28

Added

• Route params Converters
• Add search for documentation pages

Changed

• Bump dependencies

v1.3.0 - 2019-02-22

Fixed

• Versioning issue
• Multiple cookies.
• Whitenoise returns not found.
• Other bugfixes.

Added

• Stream support via resp.stream.
• Cookie directives via resp.set_cookie.
• Add resp.html to send HTML.
• Other improvements.

v1.1.3 - 2019-01-12

Changed

• Refactor _route_for

Fixed

• Resolve startup/shutdwown events

v1.2.0 - 2018-12-29

Added

• Documentations

Changed

• Use Starlette's LifeSpan middleware
• Update denpendencies

Fixed

• Fix route.is_class_based
• Fix test_500
• Typos

v1.1.2 - 2018-11-11

Fixed

• Minor fixes for Open API
• Typos

v1.1.1 - 2018-10-29

Changed

• Run sync views in a threadpoolexecutor.

v1.1.0 - 2018-10-27

Added

• Support for before_request.

v1.0.5- 2018-10-27

Fixed

• Fix sessions.

v1.0.4 - 2018-10-27

Fixed

• Potential bufix for cookies.

v1.0.3 - 2018-10-27

Fixed

• Bugfix for redirects.

v1.0.2 - 2018-10-27

Changed

• Improvement for static file hosting.

v1.0.1 - 2018-10-26

Changed

• Improve cors configuration settings.

v1.0.0 - 2018-10-26

Changed

• Move GraphQL support into a built-in plugin.

v0.3.3 - 2018-10-25

Added

• CORS support

Changed

• Improved exceptions.

v0.3.2 - 2018-10-25

Changed

• Subtle improvements.

v0.3.1 - 2018-10-24

Fixed

• Packaging fix.

v0.3.0 - 2018-10-24

Changed

• Interactive Documentation endpoint.
• Minor improvements.

v0.2.3 - 2018-10-24

Changed

• Overall improvements.

v0.2.2 - 2018-10-23

Added

• Show traceback info when background tasks raise exceptions.

v0.2.1 - 2018-10-23

Added

• api.requests.

v0.2.0 - 2018-10-22

Added

• WebSocket support.

v0.1.6 - 2018-10-20

Added

• 500 support.

v0.1.5 - 2018-10-20

Added

• File upload support

Changed

• Improvements to sequential media reading.

v0.1.4 - 2018-10-19

Fixed

• Stability.

v0.1.3 - 2018-10-18

Added

• Sessions support.

v0.1.2 - 2018-10-18

Added

• Cookies support.

v0.1.1 - 2018-10-17

Changed

• Default routes.

v0.1.0 - 2018-10-17

Added

• Prototype of static application support.

v0.0.10 - 2018-10-17

Fixed

• Bugfix for async class-based views.

v0.0.9 - 2018-10-17

Fixed

• Bugfix for async class-based views.

v0.0.8 - 2018-10-17

Added

• GraphiQL Support.

Changed

• Improvement to route selection.

v0.0.7 - 2018-10-16

Changed

• Immutable Request object.

v0.0.6 - 2018-10-16

Added

• Ability to mount WSGI apps.
• Supply content-type when serving up the schema.

v0.0.5 - 2018-10-15

Added

• OpenAPI Schema support.
• Safe load/dump yaml.

v0.0.4 - 2018-10-15

Added

• Asynchronous support for data uploads.

Fixed

• Bug fixes.

v0.0.3 - 2018-10-13

Fixed

• Bug fixes.

v0.0.2 - 2018-10-13

Changed

• Switch to ASGI/Starlette.

v0.0.1 - 2018-10-12

Added

• Conception!