werkzeug

Released 2026-04-02

• Request.host and get_host return the empty string if the header is missing or has invalid characters. 3142

Released 2026-02-19

• safe_join on Windows does not allow special devices names in multi-segment paths. 29vq-49wr-vm6x

• Response.make_conditional sets the Accept-Ranges header even if it is not a satisfiable range request. 3108

Released 2026-01-08

• safe_join on Windows does not allow more special device names, regardless of extension or surrounding spaces. 87hc-h4r5-73f7

• The multipart form parser handles a \r\n sequence at a chunk boundary. This fixes the previous attempt, which caused incorrect content lengths. 3065 3077

• Fix AttributeError when initializing DebuggedApplication with pin_security=False. 3075

Released 2024-11-04

• Improve type annotation for TypeConversionDict.get to allow the type parameter to be a callable. 2988

• Headers does not inherit from MutableMapping, as it is does not exactly match that interface. 2989

Released 2024-11-01

• Fix an issue that caused str(Request.headers) to always appear empty. 2985

Released 2024-10-25

• Fix how max_form_memory_size is applied when parsing large non-file fields. q34m-jh98-gwm2

• safe_join catches certain paths on Windows that were not caught by ntpath.isabs on Python < 3.11. f9vj-2wh5-fj8j

Released 2024-04-01

• Ensure setting merge_slashes to False results in NotFound for repeated-slash requests against single slash routes. 2834

• Fix handling of TypeError in TypeConversionDict.get() to match ValueError. 2843

• Fix response_wrapper type check in test client. 2831

• Make the return type of MultiPartParser.parse more precise. 2840

• Raise an error if converter arguments cannot be parsed. 2822

Released 2023-10-24

• Fix slow multipart parsing for large parts potentially enabling DoS attacks.

Released 2023-09-30

• Remove previously deprecated code. 2768

• Deprecate the __version__ attribute. Use feature detection, or importlib.metadata.version("werkzeug"), instead. 2770

• generate_password_hash uses scrypt by default. 2769

• Add the "werkzeug.profiler" item to the WSGI environ dictionary passed to ProfilerMiddleware's filename_format function. It contains the elapsed and time values for the profiled request. 2775

• Explicitly marked the PathConverter as non path isolating. 2784

Released 2023-11-08

• Fix slow multipart parsing for large parts potentially enabling DoS attacks.

Released 2023-08-14

• Use flit_core instead of setuptools as build backend.

• Fix parsing of multipart bodies. 2734

• Adjust index of last newline in data start. 2761

• Parsing ints from header values strips spacing first. 2734

• Fix empty file streaming when testing. 2740

• Clearer error message when URL rule does not start with slash. 2750

• Accept q value can be a float without a decimal part. 2751

Released 2023-06-08

• FileStorage.content_length does not fail if the form data did not provide a value. 2726

Released 2023-06-07

• Python 3.12 compatibility. 2704

• Fix handling of invalid base64 values in Authorization.from_header. 2717

• The debugger escapes the exception message in the page title. 2719

• When binding routing.Map, a long IDNA server_name with a port does not fail encoding. 2700

• iri_to_uri shows a deprecation warning instead of an error when passing bytes. 2708

• When parsing numbers in HTTP request headers such as Content-Length, only ASCII digits are accepted rather than any format that Python's int and float accept. 2716

Released 2023-05-08

• Authorization.from_header and WWWAuthenticate.from_header detects tokens that end with base64 padding (=). 2685

• Remove usage of warnings.catch_warnings. 2690

• Remove max_form_parts restriction from standard form data parsing and only use if for multipart content. 2694

• Response will avoid converting the Location header in some cases to preserve invalid URL schemes like itms-services. 2691

Released 2023-05-01

• Fix parsing of large multipart bodies. Remove invalid leading newline, and restore parsing speed. 2658, 2675

• The cookie Path attribute is set to / by default again, to prevent clients from falling back to RFC 6265's default-path behavior. 2672, 2679

Released 2023-04-28

• Parse the cookie Expires attribute correctly in the test client. 2669

• max_content_length can only be enforced on streaming requests if the server sets wsgi.input_terminated. 2668

Released 2023-04-27

• Percent-encode plus (+) when building URLs and in test requests. 2657

• Cookie values don't quote characters defined in RFC 6265. 2659

• Include pyi files for datastructures type annotations. 2660

• Authorization and WWWAuthenticate objects can be compared for equality. 2665

Released 2023-04-25

• Drop support for Python 3.7. 2648

• Remove previously deprecated code. 2592

• Passing bytes where strings are expected is deprecated, as well as the charset and errors parameters in many places. Anywhere that was annotated, documented, or tested to accept bytes shows a warning. Removing this artifact of the transition from Python 2 to 3 removes a significant amount of overhead in instance checks and encoding cycles. In general, always work with UTF-8, the modern HTML, URL, and HTTP standards all strongly recommend this. 2602

• Deprecate the werkzeug.urls module, except for the uri_to_iri and iri_to_uri functions. Use the urllib.parse library instead. 2600

• Update which characters are considered safe when using percent encoding in URLs, based on the WhatWG URL Standard. 2601

• Update which characters are considered safe when using percent encoding for Unicode filenames in downloads. 2598

• Deprecate the safe_conversion parameter of iri_to_uri. The Location header is converted to IRI using the same process as everywhere else. 2609

• Deprecate werkzeug.wsgi.make_line_iter and make_chunk_iter. 2613

• Use modern packaging metadata with pyproject.toml instead of setup.cfg. 2574

• Request.get_json() will raise a 415 Unsupported Media Type error if the Content-Type header is not application/json, instead of a generic 400. 2550

• A URL converter's part_isolating defaults to False if its regex contains a /. 2582

• A custom converter's regex can have capturing groups without breaking the router. 2596

• The reloader can pick up arguments to python like -X dev, and does not require heuristics to determine how to reload the command. Only available on Python >= 3.10. 2589

• The Watchdog reloader ignores file opened events. Bump the minimum version of Watchdog to 2.3.0. 2603

• When using a Unix socket for the development server, the path can start with a dot. 2595

• Increase default work factor for PBKDF2 to 600,000 iterations. 2611

• parse_options_header is 2-3 times faster. It conforms to 9110, some invalid parts that were previously accepted are now ignored. 1628

• The is_filename parameter to unquote_header_value is deprecated. 2614

• Deprecate the extra_chars parameter and passing bytes to quote_header_value, the allow_token parameter to dump_header, and the cls parameter and passing bytes to parse_dict_header. 2618

• Improve parse_accept_header implementation. Parse according to 9110. Discard items with invalid q values. 1623

• quote_header_value quotes the empty string. 2618

• dump_options_header skips None values rather than using a bare key. 2618

• dump_header and dump_options_header will not quote a value if the key ends with an asterisk *.

• parse_dict_header will decode values with charsets. 2618

• Refactor the Authorization and WWWAuthenticate header data structures. 1769, 2619

  • Both classes have type, parameters, and token attributes. The token attribute supports auth schemes that use a single opaque token rather than key=value parameters, such as Bearer.

  • Neither class is a dict anymore, although they still implement getting, setting, and deleting auth[key] and auth.key syntax, as well as auth.get(key) and key in auth.

  • Both classes have a from_header class method. parse_authorization_header and parse_www_authenticate_header are deprecated.

  • The methods WWWAuthenticate.set_basic and set_digest are deprecated. Instead, an instance should be created and assigned to response.www_authenticate.

  • A list of instances can be assigned to response.www_authenticate to set multiple header values. However, accessing the property only returns the first instance.

• Refactor parse_cookie and dump_cookie. 2637

  • parse_cookie is up to 40% faster, dump_cookie is up to 60% faster.

  • Passing bytes to parse_cookie and dump_cookie is deprecated. The dump_cookie charset parameter is deprecated.

  • dump_cookie allows domain values that do not include a dot ., and strips off a leading dot.

  • dump_cookie does not set path="/" unnecessarily by default.

• Refactor the test client cookie implementation. 1060, 1680

  • The cookie_jar attribute is deprecated. http.cookiejar is no longer used for storage.

  • Domain and path matching is used when sending cookies in requests. The domain and path parameters default to localhost and /.

  • Added a get_cookie method to inspect cookies.

  • Cookies have decoded_key and decoded_value attributes to match what the app sees rather than the encoded values a client would see.

  • The first positional server_name parameter to set_cookie and delete_cookie is deprecated. Use the domain parameter instead.

  • Other parameters to delete_cookie besides domain, path, and value are deprecated.

• If request.max_content_length is set, it is checked immediately when accessing the stream, and while reading from the stream in general, rather than only during form parsing. 1513

• The development server, which must not be used in production, will exhaust the request stream up to 10GB or 1000 reads. This allows clients to see a 413 error if max_content_length is exceeded, instead of a "connection reset" failure. 2620

• The development server discards header keys that contain underscores _, as they are ambiguous with dashes - in WSGI. 2622

• secure_filename looks for more Windows reserved file names. 2623

• Update type annotation for best_match to make default parameter clearer. 2625

• Multipart parser handles empty fields correctly. 2632

• The Map charset parameter and Request.url_charset property are deprecated. Percent encoding in URLs must always represent UTF-8 bytes. Invalid bytes are left percent encoded rather than replaced. 2602

• The Request.charset, Request.encoding_errors, Response.charset, and Client.charset attributes are deprecated. Request and response data must always use UTF-8. 2602

• Header values that have charset information only allow ASCII, UTF-8, and ISO-8859-1. 2614, 2641

• Update type annotation for ProfilerMiddleware stream parameter. 2642

• Use postponed evaluation of annotations. 2644

• The development server escapes ASCII control characters in decoded URLs before logging the request to the terminal. 2652

• The FormDataParser parse_functions attribute and get_parse_func method, and the invalid application/x-url-encoded content type, are deprecated. 2653

• generate_password_hash supports scrypt. Plain hash methods are deprecated, only scrypt and pbkdf2 are supported. 2654

Released 2023-02-14

• Ensure that URL rules using path converters will redirect with strict slashes when the trailing slash is missing. 2533

• Type signature for get_json specifies that return type is not optional when silent=False. 2508

• parse_content_range_header returns None for a value like bytes */-1 where the length is invalid, instead of raising an AssertionError. 2531

• Address remaining ResourceWarning related to the socket used by run_simple. Remove prepare_socket, which now happens when creating the server. 2421

• Update pre-existing headers for multipart/form-data requests with the test client. 2549

• Fix handling of header extended parameters such that they are no longer quoted. 2529

• LimitedStream.read works correctly when wrapping a stream that may not return the requested size in one read call. 2558

• A cookie header that starts with = is treated as an empty key and discarded, rather than stripping the leading ==.

• Specify a maximum number of multipart parts, default 1000, after which a RequestEntityTooLarge exception is raised on parsing. This mitigates a DoS attack where a larger number of form/file parts would result in disproportionate resource use.

Released 2022-08-08

• Fix router to restore the 2.1 strict_slashes == False behaviour whereby leaf-requests match branch rules and vice versa. 2489

• Fix router to identify invalid rules rather than hang parsing them, and to correctly parse / within converter arguments. 2489

• Update subpackage imports in werkzeug.routing to use the import as syntax for explicitly re-exporting public attributes. 2493

• Parsing of some invalid header characters is more robust. 2494

• When starting the development server, a warning not to use it in a production deployment is always shown. 2480

• LocalProxy.__wrapped__ is always set to the wrapped object when the proxy is unbound, fixing an issue in doctest that would cause it to fail. 2485

• Address one ResourceWarning related to the socket used by run_simple. 2421

Released 2022-07-27

• Fix router so that /path/ will match a rule /path if strict slashes mode is disabled for the rule. 2467

• Fix router so that partial part matches are not allowed i.e. /2df does not match /<int>. 2470

• Fix router static part weighting, so that simpler routes are matched before more complex ones. 2471

• Restore ValidationError to be importable from werkzeug.routing. 2465

Released 2022-07-23

• Deprecated get_script_name, get_query_string, peek_path_info, pop_path_info, and extract_path_info. 2461

• Remove previously deprecated code. 2461

• Add MarkupSafe as a dependency and use it to escape values when rendering HTML. 2419

• Added the werkzeug.debug.preserve_context mechanism for restoring context-local data for a request when running code in the debug console. 2439

• Fix compatibility with Python 3.11 by ensuring that end_lineno and end_col_offset are present on AST nodes. 2425

• Add a new faster URL matching router based on a state machine. If a custom converter needs to match a / it must set the class variable part_isolating = False. 2433

• Fix branch leaf path masking branch paths when strict-slashes is disabled. 1074

• Names within options headers are always converted to lowercase. This matches 6266 that the case is not relevant. 2442

• AnyConverter validates the value passed for it when building URLs. 2388

• The debugger shows enhanced error locations in tracebacks in Python 3.11. 2407

• Added Sans-IO is_resource_modified and parse_cookie functions based on WSGI versions. 2408

• Added Sans-IO get_content_length function. 2415

• Don't assume a mimetype for test responses. 2450

• Type checking FileStorage accepts os.PathLike. 2418

Released 2022-04-28

• The development server does not set Transfer-Encoding: chunked for 1xx, 204, 304, and HEAD responses. 2375

• Response HTML for exceptions and redirects starts with <!doctype html> and <html lang=en>. 2390

• Fix ability to set some cache_control attributes to False. 2379

• Disable keep-alive connections in the development server, which are not supported sufficiently by Python's http.server. 2397

Released 2022-04-01

• ResponseCacheControl.s_maxage converts its value to an int, like max_age. 2364

Released 2022-03-28

• Drop support for Python 3.6. 2277

• Using gevent or eventlet requires greenlet>=1.0 or PyPy>=7.3.7. werkzeug.locals and contextvars will not work correctly with older versions. 2278

• Remove previously deprecated code. 2276

  • Remove the non-standard shutdown function from the WSGI environ when running the development server. See the docs for alternatives.

  • Request and response mixins have all been merged into the Request and Response classes.

  • The user agent parser and the useragents module is removed. The user_agent module provides an interface that can be subclassed to add a parser, such as ua-parser. By default it only stores the whole string.

  • The test client returns TestResponse instances and can no longer be treated as a tuple. All data is available as properties on the response.

  • Remove locals.get_ident and related thread-local code from locals, it no longer makes sense when moving to a contextvars-based implementation.

  • Remove the python -m werkzeug.serving CLI.

  • The has_key method on some mapping datastructures; use key in data instead.

  • Request.disable_data_descriptor is removed, pass shallow=True instead.

  • Remove the no_etag parameter from Response.freeze().

  • Remove the HTTPException.wrap class method.

  • Remove the cookie_date function. Use http_date instead.

  • Remove the pbkdf2_hex, pbkdf2_bin, and safe_str_cmp functions. Use equivalents in hashlib and hmac modules instead.

  • Remove the Href class.

  • Remove the HTMLBuilder class.

  • Remove the invalidate_cached_property function. Use del obj.attr instead.

  • Remove bind_arguments and validate_arguments. Use Signature.bind and inspect.signature instead.

  • Remove detect_utf_encoding, it's built-in to json.loads.

  • Remove format_string, use string.Template instead.

  • Remove escape and unescape. Use MarkupSafe instead.

• The multiple parameter of parse_options_header is deprecated. 2357

• Rely on 538 and 540 to handle decoding file names with the correct filesystem encoding. The filesystem module is removed. 1760

• Default values passed to Headers are validated the same way values added later are. 1608

• Setting CacheControl int properties, such as max_age, will convert the value to an int. 2230

• Always use socket.fromfd when restarting the dev server. 2287

• When passing a dict of URL values to Map.build, list values do not filter out None or collapse to a single value. Passing a MultiDict does collapse single items. This undoes a previous change that made it difficult to pass a list, or None values in a list, to custom URL converters. 2249

• run_simple shows instructions for dealing with "address already in use" errors, including extra instructions for macOS. 2321

• Extend list of characters considered always safe in URLs based on 3986. 2319

• Optimize the stat reloader to avoid watching unnecessary files in more cases. The watchdog reloader is still recommended for performance and accuracy. 2141

• The development server uses Transfer-Encoding: chunked for streaming responses when it is configured for HTTP/1.1. 2090, 1327, 2091

• The development server uses HTTP/1.1, which enables keep-alive connections and chunked streaming responses, when threaded or processes is enabled. 2323

• cached_property works for classes with __slots__ if a corresponding _cache_{name} slot is added. 2332

• Refactor the debugger traceback formatter to use Python's built-in traceback module as much as possible. 1753

• The TestResponse.text property is a shortcut for r.get_data(as_text=True), for convenient testing against text instead of bytes. 2337

• safe_join ensures that the path remains relative if the trusted directory is the empty string. 2349

• Percent-encoded newlines (%0a), which are decoded by WSGI servers, are considered when routing instead of terminating the match early. 2350

• The test client doesn't set duplicate headers for CONTENT_LENGTH and CONTENT_TYPE. 2348

• append_slash_redirect handles PATH_INFO with internal slashes. 1972, 2338

• The default status code for append_slash_redirect is 308 instead of 301. This preserves the request body, and matches a previous change to strict_slashes in routing. 2351

• Fix ValueError: I/O operation on closed file. with the test client when following more than one redirect. 2353

• Response.autocorrect_location_header is disabled by default. The Location header URL will remain relative, and exclude the scheme and domain, by default. 2352

• Request.get_json() will raise a 400 BadRequest error if the Content-Type header is not application/json. This makes a very common source of confusion more visible. 2339

Released 2022-02-07

• ProxyFix supports IPv6 addresses. 2262

• Type annotation for Response.make_conditional, HTTPException.get_response, and Map.bind_to_environ accepts Request in addition to WSGIEnvironment for the first parameter. 2290

• Fix type annotation for Request.user_agent_class. 2273

• Accessing LocalProxy.__class__ and __doc__ on an unbound proxy returns the fallback value instead of a method object. 2188

• Redirects with the test client set RAW_URI and REQUEST_URI correctly. 2151

Released 2021-10-05

• Handle multiple tokens in Connection header when routing WebSocket requests. 2131

• Set the debugger pin cookie secure flag when on https. 2150

• Fix type annotation for MultiDict.update to accept iterable values 2142

• Prevent double encoding of redirect URL when merge_slash=True for Rule.match. 2157

• CombinedMultiDict.to_dict with flat=False considers all component dicts when building value lists. 2189

• send_file only sets a detected Content-Encoding if as_attachment is disabled to avoid browsers saving decompressed .tar.gz files. 2149

• Fix type annotations for TypeConversionDict.get to not return an Optional value if both default and type are not None. 2169

• Fix type annotation for routing rule factories to accept Iterable[RuleFactory] instead of Iterable[Rule] for the rules parameter. 2183

• Add missing type annotation for FileStorage.__getattr__ 2155

• The debugger pin cookie is set with SameSite set to Strict instead of None to be compatible with modern browser security. 2156

• Type annotations use IO[bytes] and IO[str] instead of BinaryIO and TextIO for wider type compatibility. 2130

• Ad-hoc TLS certs are generated with SAN matching CN. 2158

• Fix memory usage for locals when using Python 3.6 or pre 0.4.17 greenlet versions. 2212

• Fix type annotation in CallbackDict, because it is not utilizing a bound TypeVar. 2235

• Fix setting CSP header options on the response. 2237

• Fix an issue with with the interactive debugger where lines would not expand on click for very long tracebacks. 2239

• The interactive debugger handles displaying an exception that does not have a traceback, such as from ProcessPoolExecutor. 2217

Released 2021-05-17

• Fix type annotation for send_file max_age callable. Don't pass pathlib.Path to max_age. 2119

• Mark top-level names as exported so type checking understands imports in user projects. 2122

• Fix some types that weren't available in Python 3.6.0. 2123

• cached_property is generic over its return type, properties decorated with it report the correct type. 2113

• Fix multipart parsing bug when boundary contains special regex characters. 2125

• Type checking understands that calling headers.get with a string default will always return a string. 2128

• If HTTPException.description is not a string, get_description will convert it to a string. 2115

Released 2021-05-11

• Drop support for Python 2 and 3.5. 1693

• Deprecate utils.format_string, use string.Template instead. 1756

• Deprecate utils.bind_arguments and utils.validate_arguments, use Signature.bind and inspect.signature instead. 1757

• Deprecate utils.HTMLBuilder. 1761

• Deprecate utils.escape and utils.unescape, use MarkupSafe instead. 1758

• Deprecate the undocumented python -m werkzeug.serving CLI. 1834

• Deprecate the environ["werkzeug.server.shutdown"] function that is available when running the development server. 1752

• Deprecate the useragents module and the built-in user agent parser. Use a dedicated parser library instead by subclassing user_agent.UserAgent and setting Request.user_agent_class. 2078

• Remove the unused, internal posixemulation module. 1759

• All datetime values are timezone-aware with tzinfo=timezone.utc. This applies to anything using http.parse_date: Request.date, .if_modified_since, .if_unmodified_since; Response.date, .expires, .last_modified, .retry_after; parse_if_range_header, and IfRange.date. When comparing values, the other values must also be aware, or these values must be made naive. When passing parameters or setting attributes, naive values are still assumed to be in UTC. 2040

• Merge all request and response wrapper mixin code into single Request and Response classes. Using the mixin classes is no longer necessary and will show a deprecation warning. Checking isinstance or issubclass against BaseRequest and BaseResponse will show a deprecation warning and check against Request or Response instead. 1963

• JSON support no longer uses simplejson if it's installed. To use another JSON module, override Request.json_module and Response.json_module. 1766

• Response.get_json() no longer caches the result, and the cache parameter is removed. 1698

• Response.freeze() generates an ETag header if one is not set. The no_etag parameter (which usually wasn't visible anyway) is no longer used. 1963

• Add a url_scheme argument to ~routing.MapAdapter.build to override the bound scheme. 1721

• Passing an empty list as a query string parameter to build() won't append an unnecessary ?. Also drop any number of None items in a list. 1992

• When passing a Headers object to a test client method or EnvironBuilder, multiple values for a key are joined into one comma separated value. This matches the HTTP spec on multi-value headers. 1655

• Setting Response.status and status_code uses identical parsing and error checking. 1658, 1728

• MethodNotAllowed and RequestedRangeNotSatisfiable take a response kwarg, consistent with other HTTP errors. 1748

• The response generated by ~exceptions.Unauthorized produces one WWW-Authenticate header per value in www_authenticate, rather than joining them into a single value, to improve interoperability with browsers and other clients. 1755

• If parse_authorization_header can't decode the header value, it returns None instead of raising a UnicodeDecodeError. 1816

• The debugger no longer uses jQuery. 1807

• The test client includes the query string in REQUEST_URI and RAW_URI. 1781

• Switch the parameter order of default_stream_factory to match the order used when calling it. 1085

• Add send_file function to generate a response that serves a file. Adapted from Flask's implementation. 265, 1850

• Add send_from_directory function to safely serve an untrusted path within a trusted directory. Adapted from Flask's implementation. 1880

• send_file takes download_name, which is passed even if as_attachment=False by using Content-Disposition: inline. download_name replaces Flask's attachment_filename. 1869

• send_file sets conditional=True and max_age=None by default. Cache-Control is set to no-cache if max_age is not set, otherwise public. This tells browsers to validate conditional requests instead of using a timed cache. max_age=None replaces Flask's cache_timeout=43200. 1882

• send_file can be called with etag="string" to set a custom ETag instead of generating one. etag replaces Flask's add_etags. 1868

• send_file sets the Content-Encoding header if an encoding is returned when guessing mimetype from download_name. 3896

• Update the defaults used by generate_password_hash. Increase PBKDF2 iterations to 260000 from 150000. Increase salt length to 16 from 8. Use secrets module to generate salt. 1935

• The reloader doesn't crash if sys.stdin is somehow None. 1915

• Add arguments to delete_cookie to match set_cookie and the attributes modern browsers expect. 1889

• utils.cookie_date is deprecated, use utils.http_date instead. The value for Set-Cookie expires is no longer "-" delimited. 2040

• Use request.headers instead of request.environ to look up header attributes. 1808

• The test Client request methods (client.get, etc.) always return an instance of TestResponse. In addition to the normal behavior of Response, this class provides request with the request that produced the response, and history to track intermediate responses when follow_redirects is used. 763, 1894

• The test Client request methods takes an auth parameter to add an Authorization header. It can be an Authorization object or a (username, password) tuple for Basic auth. 1809

• Calling response.close() on a response from the test Client will close the request input stream. This matches file behavior and can prevent a ResourceWarning in some cases. 1785

• EnvironBuilder.from_environ decodes values encoded for WSGI, to avoid double encoding the new values. 1959

• The default stat reloader will watch Python files under non-system/virtualenv sys.path entries, which should contain most user code. It will also watch all Python files under directories given in extra_files. 1945

• The reloader ignores __pycache__ directories again. 1945

• run_simple takes exclude_patterns a list of fnmatch patterns that will not be scanned by the reloader. 1333

• Cookie names are no longer unquoted. This was against 6265 and potentially allowed setting __Secure prefixed cookies. 1965

• Fix some word matches for user agent platform when the word can be a substring. 1923

• The development server logs ignored SSL errors. 1967

• Temporary files for form data are opened in rb+ instead of wb+ mode for better compatibility with some libraries. 1961

• Use SHA-1 instead of MD5 for generating ETags and the debugger pin, and in some tests. MD5 is not available in some environments, such as FIPS 140. This may invalidate some caches since the ETag will be different. 1897

• Add Cross-Origin-Opener-Policy and Cross-Origin-Embedder-Policy response header properties. 2008

• run_simple tries to show a valid IP address when binding to all addresses, instead of 0.0.0.0 or ::. It also warns about not running the development server in production in this case. 1964

• Colors in the development server log are displayed if Colorama is installed on Windows. For all platforms, style support no longer requires Click. 1832

• A range request for an empty file (or other data with length 0) will return a 200 response with the empty file instead of a 416 error. 1937

• New sans-IO base classes for Request and Response have been extracted to contain all the behavior that is not WSGI or IO dependent. These are not a public API, they are part of an ongoing refactor to let ASGI frameworks use Werkzeug. 2005

• Parsing multipart/form-data has been refactored to use sans-io patterns. This should also make parsing forms with large binary file uploads significantly faster. 1788, 875

• LocalProxy matches the current Python data model special methods, including all r-ops, in-place ops, and async. __class__ is proxied, so the proxy will look like the object in more cases, including isinstance. Use issubclass(type(obj), LocalProxy) to check if an object is actually a proxy. 1754

• Local uses ContextVar on Python 3.7+ instead of threading.local. 1778

• request.values does not include form for GET requests (even though GET bodies are undefined). This prevents bad caching proxies from caching form data instead of query strings. 2037

• The development server adds the underlying socket to environ as werkzeug.socket. This is non-standard and specific to the dev server, other servers may expose this under their own key. It is useful for handling a WebSocket upgrade request. 2052

• URL matching assumes websocket=True mode for WebSocket upgrade requests. 2052

• Updated UserAgentParser to handle more cases. 1971

• werzeug.DechunkedInput.readinto will not read beyond the size of the buffer. 2021

• Fix connection reset when exceeding max content size. 2051

• pbkdf2_hex, pbkdf2_bin, and safe_str_cmp are deprecated. hashlib and hmac provide equivalents. 2083

• invalidate_cached_property is deprecated. Use del obj.name instead. 2084

• Href is deprecated. Use werkzeug.routing instead. 2085

• Request.disable_data_descriptor is deprecated. Create the request with shallow=True instead. 2085

• HTTPException.wrap is deprecated. Create a subclass manually instead. 2085

Released 2020-03-31

• Make the argument to RequestRedirect.get_response optional. 1718

• Only allow a single access control allow origin value. 1723

• Fix crash when trying to parse a non-existent Content Security Policy header. 1731

• http_date zero fills years < 1000 to always output four digits. 1739

• Fix missing local variables in interactive debugger console. 1746

• Fix passing file-like objects like io.BytesIO to FileStorage.save. 1733

Released 2020-02-06

• Drop support for Python 3.4. (1478)

• Remove code that issued deprecation warnings in version 0.15. (1477)

• Remove most top-level attributes provided by the werkzeug module in favor of direct imports. For example, instead of import werkzeug; werkzeug.url_quote, do from werkzeug.urls import url_quote. Install version 0.16 first to see deprecation warnings while upgrading. 2, 1640

• Added utils.invalidate_cached_property() to invalidate cached properties. (1474)

• Directive keys for the Set-Cookie response header are not ignored when parsing the Cookie request header. This allows cookies with names such as "expires" and "version". (1495)

• Request cookies are parsed into a MultiDict to capture all values for cookies with the same key. cookies[key] returns the first value rather than the last. Use cookies.getlist(key) to get all values. parse_cookie also defaults to a MultiDict. 1562, 1458

• Add charset=utf-8 to an HTTP exception response's CONTENT_TYPE header. (1526)

• The interactive debugger handles outer variables in nested scopes such as lambdas and comprehensions. 913, 1037, 1532

• The user agent for Opera 60 on Mac is correctly reported as "opera" instead of "chrome". 1556

• The platform for Crosswalk on Android is correctly reported as "android" instead of "chromeos". (1572)

• Issue a warning when the current server name does not match the configured server name. 760

• A configured server name with the default port for a scheme will match the current server name without the port if the current scheme matches. 1584

• ~exceptions.InternalServerError has a original_exception attribute that frameworks can use to track the original cause of the error. 1590

• Headers are tested for equality independent of the header key case, such that X-Foo is the same as x-foo. 1605

• http.dump_cookie accepts 'None' as a value for samesite. 1549

• ~test.Client.set_cookie accepts a samesite argument. 1705

• Support the Content Security Policy header through the Response.content_security_policy data structure. 1617

• LanguageAccept will fall back to matching "en" for "en-US" or "en-US" for "en" to better support clients or translations that only match at the primary language tag. 450, 1507

• MIMEAccept uses MIME parameters for specificity when matching. 458, 1574

• If the development server is started with an SSLContext configured to verify client certificates, the certificate in PEM format will be available as environ["SSL_CLIENT_CERT"]. 1469

• is_resource_modified will run for methods other than GET and HEAD, rather than always returning False. 409

• SharedDataMiddleware returns 404 rather than 500 when trying to access a directory instead of a file with the package loader. The dependency on setuptools and pkg_resources is removed. 1599

• Add a response.cache_control.immutable flag. Keep in mind that browser support for this Cache-Control header option is still experimental and may not be implemented. 1185

• Optional request log highlighting with the development server is handled by Click instead of termcolor. 1235

• Optional ad-hoc TLS support for the development server is handled by cryptography instead of pyOpenSSL. 1555

• FileStorage.save() supports pathlib and 519 PathLike objects. 1653

• The debugger security pin is unique in containers managed by Podman. 1661

• Building a URL when host_matching is enabled takes into account the current host when there are duplicate endpoints with different hosts. 488

• The 429 TooManyRequests and 503 ServiceUnavailable HTTP exceptions takes a retry_after parameter to set the Retry-After header. 1657

• Map and Rule have a merge_slashes option to collapse multiple slashes into one, similar to how many HTTP servers behave. This is enabled by default. 1286, 1694

• Add HTTP 103, 208, 306, 425, 506, 508, and 511 to the list of status codes. 1678

• Add update, setlist, and setlistdefault methods to the Headers data structure. extend method can take MultiDict and kwargs. 1687, 1697

• The development server accepts paths that start with two slashes, rather than stripping off the first path segment. 491

• Add access control (Cross Origin Request Sharing, CORS) header properties to the Request and Response wrappers. 1699

• Accept values are no longer ordered alphabetically for equal quality tags. Instead the initial order is preserved. 1686

• Added Map.lock_class attribute for alternative implementations. 1702

• Support matching and building WebSocket rules in the routing system, for use by async frameworks. 1709

• Range requests that span an entire file respond with 206 instead of 200, to be more compliant with 7233. This may help serving media to older browsers. 410, 1704

• The ~middleware.shared_data.SharedDataMiddleware default fallback_mimetype is application/octet-stream. If a filename looks like a text mimetype, the utf-8 charset is added to it. This matches the behavior of ~wrappers.BaseResponse and Flask's send_file(). 1689

Released 2020-01-27

• Fix import location in deprecation messages for subpackages. 1663

• Fix an SSL error on Python 3.5 when the dev server responds with no content. 1659

Released 2019-09-19

• Deprecate most top-level attributes provided by the werkzeug module in favor of direct imports. The deprecated imports will be removed in version 1.0.

  For example, instead of import werkzeug; werkzeug.url_quote, do from werkzeug.urls import url_quote. A deprecation warning will show the correct import to use. werkzeug.exceptions and werkzeug.routing should also be imported instead of accessed, but for technical reasons can't show a warning.

  2, 1640

Released 2019-09-04

• Work around a bug in pip that caused the reloader to fail on Windows when the script was an entry point. This fixes the issue with Flask's flask run command failing with "No module named Scriptsflask". 1614

• ProxyFix trusts the X-Forwarded-Proto header by default. 1630

• The deprecated num_proxies argument to ProxyFix sets x_for, x_proto, and x_host to match 0.14 behavior. This is intended to make intermediate upgrades less disruptive, but the argument will still be removed in 1.0. 1630

Released 2019-07-17

• Fix a TypeError due to changes to ast.Module in Python 3.8. 1551

• Fix a C assertion failure in debug builds of some Python 2.7 releases. 1553

• ~exceptions.BadRequestKeyError adds the KeyError message to the description if e.show_exception is set to True. This is a more secure default than the original 0.15.0 behavior and makes it easier to control without losing information. 1592

• Upgrade the debugger to jQuery 3.4.1. 1581

• Work around an issue in some external debuggers that caused the reloader to fail. 1607

• Work around an issue where the reloader couldn't introspect a setuptools script installed as an egg. 1600

• The reloader will use sys.executable even if the script is marked executable, reverting a behavior intended for NixOS introduced in 0.15. The reloader should no longer cause OSError: [Errno 8] Exec format error. 1482, 1580

• SharedDataMiddleware safely handles paths with Windows drive names. 1589

Released 2019-05-14

• Fix a SyntaxError on Python 2.7.5. (1544)

Released 2019-05-14

• Properly handle multi-line header folding in development server in Python 2.7. (1080)

• Restore the response argument to ~exceptions.Unauthorized. (1527)

• ~exceptions.Unauthorized doesn't add the WWW-Authenticate header if www_authenticate is not given. (1516)

• The default URL converter correctly encodes bytes to string rather than representing them with b''. (1502)

• Fix the filename format string in ~middleware.profiler.ProfilerMiddleware to correctly handle float values. (1511)

• Update ~middleware.lint.LintMiddleware to work on Python 3. (1510)

• The debugger detects cycles in chained exceptions and does not time out in that case. (1536)

• When running the development server in Docker, the debugger security pin is now unique per container.

Released 2019-04-02

• Rule code generation uses a filename that coverage will ignore. The previous value, "generated", was causing coverage to fail. (1487)

• The test client removes the cookie header if there are no persisted cookies. This fixes an issue introduced in 0.15.0 where the cookies from the original request were used for redirects, causing functions such as logout to fail. (1491)

• The test client copies the environ before passing it to the app, to prevent in-place modifications from affecting redirect requests. (1498)

• The "werkzeug" logger only adds a handler if there is no handler configured for its level in the logging chain. This avoids double logging if other code configures logging first. (1492)

Released 2019-03-21

• ~exceptions.Unauthorized takes description as the first argument, restoring previous behavior. The new www_authenticate argument is listed second. (1483)

Released 2019-03-19

• Building URLs is ~7x faster. Each ~routing.Rule compiles an optimized function for building itself. (1281)

• MapAdapter.build() can be passed a ~datastructures.MultiDict to represent multiple values for a key. It already did this when passing a dict with a list value. (724)

• path_info defaults to '/' for Map.bind(). (740, 768, 1316)

• Change RequestRedirect code from 301 to 308, preserving the verb and request body (form data) during redirect. (1342)

• int and float converters in URL rules will handle negative values if passed the signed=True parameter. For example, /jump/<int(signed=True):count>. (1355)

• Location autocorrection in Response.get_wsgi_headers() is relative to the current path rather than the root path. (693, 718, 1315)

• 412 responses once again include entity headers and an error message in the body. They were originally omitted when implementing If-Match (1233), but the spec doesn't seem to disallow it. (1231, 1255)

• The Content-Length header is removed for 1xx and 204 responses. This fixes a previous change where no body would be sent, but the header would still be present. The new behavior matches RFC 7230. (1294)

• ~exceptions.Unauthorized takes a www_authenticate parameter to set the WWW-Authenticate header for the response, which is technically required for a valid 401 response. (772, 795)

• Add support for status code 424 ~exceptions.FailedDependency. (1358)

• http.parse_cookie ignores empty segments rather than producing a cookie with no key or value. (1245, 1301)

• http.parse_authorization_header (and ~datastructures.Authorization, ~wrappers.Request.authorization) treats the authorization header as UTF-8. On Python 2, basic auth username and password are unicode. (1325)

• ~http.parse_options_header understands 2231 parameter continuations. (1417)

• ~urls.uri_to_iri does not unquote ASCII characters in the unreserved class, such as space, and leaves invalid bytes quoted when decoding. ~urls.iri_to_uri does not quote reserved characters. See 3987 for these character classes. (1433)

• get_content_type appends a charset for any mimetype that ends with +xml, not just those that start with application/. Known text types such as application/javascript are also given charsets. (1439)

• Clean up werkzeug.security module, remove outdated hashlib support. (1282)

• In ~security.generate_password_hash, PBKDF2 uses 150000 iterations by default, increased from 50000. (1377)

• ~wsgi.ClosingIterator calls close on the wrapped iterable, not the internal iterator. This doesn't affect objects where __iter__ returned self. For other objects, the method was not called before. (1259, 1260)

• Bytes may be used as keys in ~datastructures.Headers, they will be decoded as Latin-1 like values are. (1346)

• ~datastructures.Range validates that list of range tuples passed to it would produce a valid Range header. (1412)

• ~datastructures.FileStorage looks up attributes on stream._file if they don't exist on stream, working around an issue where tempfile.SpooledTemporaryFile didn't implement all of io.IOBase. See https://github.com/python/cpython/pull/3249. (1409)

• CombinedMultiDict.copy() returns a shallow mutable copy as a ~datastructures.MultiDict. The copy no longer reflects changes to the combined dicts, but is more generally useful. (1420)

• The version of jQuery used by the debugger is updated to 3.3.1. (1390)

• The debugger correctly renders long markupsafe.Markup instances. (1393)

• The debugger can serve resources when Werkzeug is installed as a zip file. DebuggedApplication.get_resource uses pkgutil.get_data. (1401)

• The debugger and server log support Python 3's chained exceptions. (1396)

• The interactive debugger highlights frames that come from user code to make them easy to pick out in a long stack trace. Note that if an env was created with virtualenv instead of venv, the debugger may incorrectly classify some frames. (1421)

• Clicking the error message at the top of the interactive debugger will jump down to the bottom of the traceback. (1422)

• When generating a PIN, the debugger will ignore a KeyError raised when the current UID doesn't have an associated username, which can happen in Docker. (1471)

• ~exceptions.BadRequestKeyError adds the KeyError message to the description, making it clearer what caused the 400 error. Frameworks like Flask can omit this information in production by setting e.args = (). (1395)

• If a nested ImportError occurs from ~utils.import_string the traceback mentions the nested import. Removes an untested code path for handling "modules not yet set up by the parent." (735)

• Triggering a reload while using a tool such as PDB no longer hides input. (1318)

• The reloader will not prepend the Python executable to the command line if the Python file is marked executable. This allows the reloader to work on NixOS. (1242)

• Fix an issue where sys.path would change between reloads when running with python -m app. The reloader can detect that a module was run with "-m" and reconstructs that instead of the file path in sys.argv when reloading. (1416)

• The dev server can bind to a Unix socket by passing a hostname like unix://app.socket. (209, 1019)

• Server uses IPPROTO_TCP constant instead of SOL_TCP for Jython compatibility. (1375)

• When using an adhoc SSL cert with ~serving.run_simple, the cert is shown as self-signed rather than signed by an invalid authority. (1430)

• The development server logs the unquoted IRI rather than the raw request line, to make it easier to work with Unicode in request paths during development. (1115)

• The development server recognizes ConnectionError on Python 3 to silence client disconnects, and does not silence other OSErrors that may have been raised inside the application. (1418)

• The environ keys REQUEST_URI and RAW_URI contain the raw path before it was percent-decoded. This is non-standard, but many WSGI servers add them. Middleware could replace PATH_INFO with this to route based on the raw value. (1419)

• ~test.EnvironBuilder doesn't set CONTENT_TYPE or CONTENT_LENGTH in the environ if they aren't set. Previously these used default values if they weren't set. Now it's possible to distinguish between empty and unset values. (1308)

• The test client raises a ValueError if a query string argument would overwrite a query string in the path. (1338)

• test.EnvironBuilder and test.Client take a json argument instead of manually passing data and content_type. This is serialized using the test.EnvironBuilder.json_dumps method. (1404)

• test.Client redirect handling is rewritten. (1402)

  • The redirect environ is copied from the initial request environ.

  • Script root and path are correctly distinguished when redirecting to a path under the root.

  • The HEAD method is not changed to GET.

  • 307 and 308 codes preserve the method and body. All others ignore the body and related headers.

  • Headers are passed to the new request for all codes, following what browsers do.

  • test.EnvironBuilder sets the content type and length headers in addition to the WSGI keys when detecting them from the data.

  • Intermediate response bodies are iterated over even when buffered=False to ensure iterator middleware can run cleanup code safely. Only the last response is not buffered. (988)

• ~test.EnvironBuilder, ~datastructures.FileStorage, and wsgi.get_input_stream no longer share a global _empty_stream instance. This improves test isolation by preventing cases where closing the stream in one request would affect other usages. (1340)

• The default SecureCookie.serialization_method will change from pickle to json in 1.0. To upgrade existing tokens, override ~contrib.securecookie.SecureCookie.unquote to try pickle if json fails. (1413)

• CGIRootFix no longer modifies PATH_INFO for very old versions of Lighttpd. LighttpdCGIRootFix was renamed to CGIRootFix in 0.9. Both are deprecated and will be removed in version 1.0. (1141)

• werkzeug.wrappers.json.JSONMixin has been replaced with Flask's implementation. Check the docs for the full API. (1445)

• The contrib modules are deprecated and will either be moved into werkzeug core or removed completely in version 1.0. Some modules that already issued deprecation warnings have been removed. Be sure to run or test your code with python -W default::DeprecationWarning to catch any deprecated code you're using. (4)

  • LintMiddleware has moved to werkzeug.middleware.lint.

  • ProfilerMiddleware has moved to werkzeug.middleware.profiler.

  • ProxyFix has moved to werkzeug.middleware.proxy_fix.

  • JSONRequestMixin has moved to werkzeug.wrappers.json.

  • cache has been extracted into a separate project, cachelib. The version in Werkzeug is deprecated.

  • securecookie and sessions have been extracted into a separate project, secure-cookie. The version in Werkzeug is deprecated.

  • Everything in fixers, except ProxyFix, is deprecated.

  • Everything in wrappers, except JSONMixin, is deprecated.

  • atom is deprecated. This did not fit in with the rest of Werkzeug, and is better served by a dedicated library in the community.

  • jsrouting is removed. Set URLs when rendering templates or JSON responses instead.

  • limiter is removed. Its specific use is handled by Werkzeug directly, but stream limiting is better handled by the WSGI server in general.

  • testtools is removed. It did not offer significant benefit over the default test client.

  • iterio is deprecated.

• wsgi.get_host no longer looks at X-Forwarded-For. Use ~middleware.proxy_fix.ProxyFix to handle that. (609, 1303)

• ~middleware.proxy_fix.ProxyFix is refactored to support more headers, multiple values, and more secure configuration.

  • Each header supports multiple values. The trusted number of proxies is configured separately for each header. The num_proxies argument is deprecated. (1314)

  • Sets SERVER_NAME and SERVER_PORT based on X-Forwarded-Host. (1314)

  • Sets SERVER_PORT and modifies HTTP_HOST based on X-Forwarded-Port. (1023, 1304)

  • Sets SCRIPT_NAME based on X-Forwarded-Prefix. (1237)

  • The original WSGI environment values are stored in the werkzeug.proxy_fix.orig key, a dict. The individual keys werkzeug.proxy_fix.orig_remote_addr, werkzeug.proxy_fix.orig_wsgi_url_scheme, and werkzeug.proxy_fix.orig_http_host are deprecated.

• Middleware from werkzeug.wsgi has moved to separate modules under werkzeug.middleware, along with the middleware moved from werkzeug.contrib. The old werkzeug.wsgi imports are deprecated and will be removed in version 1.0. (1452)

  • werkzeug.wsgi.DispatcherMiddleware has moved to werkzeug.middleware.dispatcher.DispatcherMiddleware.

  • werkzeug.wsgi.ProxyMiddleware as moved to werkzeug.middleware.http_proxy.ProxyMiddleware.

  • werkzeug.wsgi.SharedDataMiddleware has moved to werkzeug.middleware.shared_data.SharedDataMiddleware.

• ~middleware.http_proxy.ProxyMiddleware proxies the query string. (1252)

• The filenames generated by ~middleware.profiler.ProfilerMiddleware can be customized. (1283)

• The werkzeug.wrappers module has been converted to a package, and its various classes have been organized into separate modules. Any previously documented classes, understood to be the existing public API, are still importable from werkzeug.wrappers, or may be imported from their specific modules. (1456)

Released on December 7th 2017

• Deprecate support for Python 2.6 and 3.3. CI tests will not run for these versions, and support will be dropped completely in the next version. (pallets/meta#24)

• Raise TypeError when port is not an integer. (1088)

• Fully deprecate werkzeug.script. Use Click instead. (1090)

• response.age is parsed as a timedelta. Previously, it was incorrectly treated as a datetime. The header value is an integer number of seconds, not a date string. (414)

• Fix a bug in TypeConversionDict where errors are not propagated when using the converter. (1102)

• Authorization.qop is a string instead of a set, to comply with RFC 2617. (984)

• An exception is raised when an encoded cookie is larger than, by default, 4093 bytes. Browsers may silently ignore cookies larger than this. BaseResponse has a new attribute max_cookie_size and dump_cookie has a new argument max_size to configure this. (780, 1109)

• Fix a TypeError in werkzeug.contrib.lint.GuardedIterator.close. (1116)

• BaseResponse.calculate_content_length now correctly works for Unicode responses on Python 3. It first encodes using iter_encoded. (705)

• Secure cookie contrib works with string secret key on Python 3. (1205)

• Shared data middleware accepts a list instead of a dict of static locations to preserve lookup order. (1197)

• HTTP header values without encoding can contain single quotes. (1208)

• The built-in dev server supports receiving requests with chunked transfer encoding. (1198)