Changes¶
Version 2.0.3¶
Released 2022-02-14
The test client’s
as_tuple
parameter is deprecated and will be removed in Werkzeug 2.1. It is now also deprecated in Flask, to be removed in Flask 2.1, while remaining compatible with both in 2.0.x. Useresponse.request.environ
instead. #4341Fix type annotation for
errorhandler
decorator. #4295Revert a change to the CLI that caused it to hide
ImportError
tracebacks when importing the application. #4307app.json_encoder
andjson_decoder
are only passed todumps
andloads
if they have custom behavior. This improves performance, mainly on PyPy. #4349Clearer error message when
after_this_request
is used outside a request context. #4333
Version 2.0.2¶
Released 2021-10-04
Fix type annotation for
teardown_*
methods. #4093Fix type annotation for
before_request
andbefore_app_request
decorators. #4104Fixed the issue where typing requires template global decorators to accept functions with no arguments. #4098
Support View and MethodView instances with async handlers. #4112
Enhance typing of
app.errorhandler
decorator. #4095Fix registering a blueprint twice with differing names. #4124
Fix the type of
static_folder
to acceptpathlib.Path
. #4150jsonify
handlesdecimal.Decimal
by encoding tostr
. #4157Correctly handle raising deferred errors in CLI lazy loading. #4096
The CLI loader handles
**kwargs
in acreate_app
function. #4170Fix the order of
before_request
and other callbacks that trigger before the view returns. They are called from the app down to the closest nested blueprint. #4229
Version 2.0.1¶
Released 2021-05-21
Re-add the
filename
parameter insend_from_directory
. Thefilename
parameter has been renamed topath
, the old name is deprecated. #4019Mark top-level names as exported so type checking understands imports in user projects. #4024
Fix type annotation for
g
and inform mypy that it is a namespace object that has arbitrary attributes. #4020Fix some types that weren’t available in Python 3.6.0. #4040
Improve typing for
send_file
,send_from_directory
, andget_send_file_max_age
. #4044, #4026Show an error when a blueprint name contains a dot. The
.
has special meaning, it is used to separate (nested) blueprint names and the endpoint name. #4041Combine URL prefixes when nesting blueprints that were created with a
url_prefix
value. #4037Roll back a change to the order that URL matching was done. The URL is again matched after the session is loaded, so the session is available in custom URL converters. #4053
Re-add deprecated
Config.from_json
, which was accidentally removed early. #4078Improve typing for some functions using
Callable
in their type signatures, focusing on decorator factories. #4060Nested blueprints are registered with their dotted name. This allows different blueprints with the same name to be nested at different locations. #4069
register_blueprint
takes aname
option to change the (pre-dotted) name the blueprint is registered with. This allows the same blueprint to be registered multiple times with unique names forurl_for
. Registering the same blueprint with the same name multiple times is deprecated. #1091Improve typing for
stream_with_context
. #4052
Version 2.0.0¶
Released 2021-05-11
Drop support for Python 2 and 3.5.
Bump minimum versions of other Pallets projects: Werkzeug >= 2, Jinja2 >= 3, MarkupSafe >= 2, ItsDangerous >= 2, Click >= 8. Be sure to check the change logs for each project. For better compatibility with other applications (e.g. Celery) that still require Click 7, there is no hard dependency on Click 8 yet, but using Click 7 will trigger a DeprecationWarning and Flask 2.1 will depend on Click 8.
JSON support no longer uses simplejson. To use another JSON module, override
app.json_encoder
andjson_decoder
. #3555The
encoding
option to JSON functions is deprecated. #3562Passing
script_info
to app factory functions is deprecated. This was not portable outside theflask
command. Useclick.get_current_context().obj
if it’s needed. #3552The CLI shows better error messages when the app failed to load when looking up commands. #2741
Add
sessions.SessionInterface.get_cookie_name()
to allow setting the session cookie name dynamically. #3369Add
Config.from_file()
to load config using arbitrary file loaders, such astoml.load
orjson.load
.Config.from_json()
is deprecated in favor of this. #3398The
flask run
command will only defer errors on reload. Errors present during the initial call will cause the server to exit with the traceback immediately. #3431send_file()
raises aValueError
when passed anio
object in text mode. Previously, it would respond with 200 OK and an empty file. #3358When using ad-hoc certificates, check for the cryptography library instead of PyOpenSSL. #3492
When specifying a factory function with
FLASK_APP
, keyword argument can be passed. #3553When loading a
.env
or.flaskenv
file, the current working directory is no longer changed to the location of the file. #3560When returning a
(response, headers)
tuple from a view, the headers replace rather than extend existing headers on the response. For example, this allows setting theContent-Type
forjsonify()
. Useresponse.headers.extend()
if extending is desired. #3628The
Scaffold
class provides a common API for theFlask
andBlueprint
classes.Blueprint
information is stored in attributes just likeFlask
, rather than opaque lambda functions. This is intended to improve consistency and maintainability. #3215Include
samesite
andsecure
options when removing the session cookie. #3726Support passing a
pathlib.Path
tostatic_folder
. #3579send_file
andsend_from_directory
are wrappers around the implementations inwerkzeug.utils
. #3828Some
send_file
parameters have been renamed, the old names are deprecated.attachment_filename
is renamed todownload_name
.cache_timeout
is renamed tomax_age
.add_etags
is renamed toetag
. #3828, #3883send_file
passesdownload_name
even ifas_attachment=False
by usingContent-Disposition: inline
. #3828send_file
setsconditional=True
andmax_age=None
by default.Cache-Control
is set tono-cache
ifmax_age
is not set, otherwisepublic
. This tells browsers to validate conditional requests instead of using a timed cache. #3828helpers.safe_join
is deprecated. Usewerkzeug.utils.safe_join
instead. #3828The request context does route matching before opening the session. This could allow a session interface to change behavior based on
request.endpoint
. #3776Use Jinja’s implementation of the
|tojson
filter. #3881Add route decorators for common HTTP methods. For example,
@app.post("/login")
is a shortcut for@app.route("/login", methods=["POST"])
. #3907Support async views, error handlers, before and after request, and teardown functions. #3412
Set the default encoding to “UTF-8” when loading
.env
and.flaskenv
files to allow to use non-ASCII characters. #3931flask shell
sets up tab and history completion like the defaultpython
shell ifreadline
is installed. #3941helpers.total_seconds()
is deprecated. Usetimedelta.total_seconds()
instead. #3962Add type hinting. #3973.
Version 1.1.4¶
Released 2021-05-13
Update
static_folder
to use_compat.fspath
instead ofos.fspath
to continue supporting Python < 3.6 #4050
Version 1.1.3¶
Released 2021-05-13
Version 1.1.2¶
Released 2020-04-03
Version 1.1.1¶
Released 2019-07-08
The
flask.json_available
flag was added back for compatibility with some extensions. It will raise a deprecation warning when used, and will be removed in version 2.0.0. #3288
Version 1.1.0¶
Released 2019-07-04
Bump minimum Werkzeug version to >= 0.15.
Drop support for Python 3.4.
Error handlers for
InternalServerError
or500
will always be passed an instance ofInternalServerError
. If they are invoked due to an unhandled exception, that original exception is now available ase.original_exception
rather than being passed directly to the handler. The same is true if the handler is for the baseHTTPException
. This makes error handler behavior more consistent. #3266Flask.finalize_request()
is called for all unhandled exceptions even if there is no500
error handler.
Flask.logger
takes the same name asFlask.name
(the value passed asFlask(import_name)
. This reverts 1.0’s behavior of always logging to"flask.app"
, in order to support multiple apps in the same process. A warning will be shown if old configuration is detected that needs to be moved. #2866flask.RequestContext.copy()
includes the current session object in the request context copy. This preventssession
pointing to an out-of-date object. #2935Using built-in RequestContext, unprintable Unicode characters in Host header will result in a HTTP 400 response and not HTTP 500 as previously. #2994
send_file()
supportsPathLike
objects as described in PEP 0519, to supportpathlib
in Python 3. #3059send_file()
supportsBytesIO
partial content. #2957open_resource()
accepts the “rt” file mode. This still does the same thing as “r”. #3163The
MethodView.methods
attribute set in a base class is used by subclasses. #3138Flask.jinja_options
is adict
instead of anImmutableDict
to allow easier configuration. Changes must still be made before creating the environment. #3190Flask’s
JSONMixin
for the request and response wrappers was moved into Werkzeug. Use Werkzeug’s version with Flask-specific support. This bumps the Werkzeug dependency to >= 0.15. #3125The
flask
command entry point is simplified to take advantage of Werkzeug 0.15’s better reloader support. This bumps the Werkzeug dependency to >= 0.15. #3022Support
static_url_path
that ends with a forward slash. #3134Support empty
static_folder
without requiring setting an emptystatic_url_path
as well. #3124jsonify()
supportsdataclasses.dataclass
objects. #3195Allow customizing the
Flask.url_map_class
used for routing. #3069The development server port can be set to 0, which tells the OS to pick an available port. #2926
The return value from
cli.load_dotenv()
is more consistent with the documentation. It will returnFalse
if python-dotenv is not installed, or if the given path isn’t a file. #2937Signaling support has a stub for the
connect_via
method when the Blinker library is not installed. #3208Add an
--extra-files
option to theflask run
CLI command to specify extra files that will trigger the reloader on change. #2897Allow returning a dictionary from a view function. Similar to how returning a string will produce a
text/html
response, returning a dict will calljsonify
to produce aapplication/json
response. #3111Blueprints have a
cli
Click group likeapp.cli
. CLI commands registered with a blueprint will be available as a group under theflask
command. #1357.When using the test client as a context manager (
with client:
), all preserved request contexts are popped when the block exits, ensuring nested contexts are cleaned up correctly. #3157Show a better error message when the view return type is not supported. #3214
flask.testing.make_test_environ_builder()
has been deprecated in favour of a new classflask.testing.EnvironBuilder
. #3232The
flask run
command no longer fails if Python is not built with SSL support. Using the--cert
option will show an appropriate error message. #3211URL matching now occurs after the request context is pushed, rather than when it’s created. This allows custom URL converters to access the app and request contexts, such as to query a database for an id. #3088
Version 1.0.4¶
Released 2019-07-04
The key information for
BadRequestKeyError
is no longer cleared outside debug mode, so error handlers can still access it. This requires upgrading to Werkzeug 0.15.5. #3249send_file
url quotes the “:” and “/” characters for more compatible UTF-8 filename support in some browsers. #3074Fixes for PEP451 import loaders and pytest 5.x. #3275
Show message about dotenv on stderr instead of stdout. #3285
Version 1.0.3¶
Released 2019-05-17
send_file()
encodes filenames as ASCII instead of Latin-1 (ISO-8859-1). This fixes compatibility with Gunicorn, which is stricter about header encodings than PEP 3333. #2766Allow custom CLIs using
FlaskGroup
to set the debug flag without it always being overwritten based on environment variables. #2765flask --version
outputs Werkzeug’s version and simplifies the Python version. #2825send_file()
handles anattachment_filename
that is a native Python 2 string (bytes) with UTF-8 coded bytes. #2933A catch-all error handler registered for
HTTPException
will not handleRoutingException
, which is used internally during routing. This fixes the unexpected behavior that had been introduced in 1.0. #2986Passing the
json
argument toapp.test_client
does not push/pop an extra app context. #2900
Version 1.0.2¶
Released 2018-05-02
Version 1.0.1¶
Released 2018-04-29
Fix registering partials (with no
__name__
) as view functions. #2730Don’t treat lists returned from view functions the same as tuples. Only tuples are interpreted as response data. #2736
Extra slashes between a blueprint’s
url_prefix
and a route URL are merged. This fixes some backwards compatibility issues with the change in 1.0. #2731, #2742Only trap
BadRequestKeyError
errors in debug mode, not allBadRequest
errors. This allowsabort(400)
to continue working as expected. #2735The
FLASK_SKIP_DOTENV
environment variable can be set to1
to skip automatically loading dotenv files. #2722
Version 1.0¶
Released 2018-04-26
Python 2.6 and 3.3 are no longer supported.
Bump minimum dependency versions to the latest stable versions: Werkzeug >= 0.14, Jinja >= 2.10, itsdangerous >= 0.24, Click >= 5.1. #2586
Skip
app.run
when a Flask application is run from the command line. This avoids some behavior that was confusing to debug.Change the default for
JSONIFY_PRETTYPRINT_REGULAR
toFalse
.jsonify()
returns a compact format by default, and an indented format in debug mode. #2193Flask.__init__
accepts thehost_matching
argument and sets it onurl_map
. #1559Flask.__init__
accepts thestatic_host
argument and passes it as thehost
argument when defining the static route. #1559send_file()
supports Unicode inattachment_filename
. #2223Pass
_scheme
argument fromurl_for()
tohandle_url_build_error()
. #2017add_url_rule()
accepts theprovide_automatic_options
argument to disable adding theOPTIONS
method. #1489MethodView
subclasses inherit method handlers from base classes. #1936Errors caused while opening the session at the beginning of the request are handled by the app’s error handlers. #2254
Blueprints gained
json_encoder
andjson_decoder
attributes to override the app’s encoder and decoder. #1898Flask.make_response()
raisesTypeError
instead ofValueError
for bad response types. The error messages have been improved to describe why the type is invalid. #2256Add
routes
CLI command to output routes registered on the application. #2259Show warning when session cookie domain is a bare hostname or an IP address, as these may not behave properly in some browsers, such as Chrome. #2282
Allow IP address as exact session cookie domain. #2282
SESSION_COOKIE_DOMAIN
is set if it is detected throughSERVER_NAME
. #2282Auto-detect zero-argument app factory called
create_app
ormake_app
fromFLASK_APP
. #2297Factory functions are not required to take a
script_info
parameter to work with theflask
command. If they take a single parameter or a parameter namedscript_info
, theScriptInfo
object will be passed. #2319FLASK_APP
can be set to an app factory, with arguments if needed, for exampleFLASK_APP=myproject.app:create_app('dev')
. #2326FLASK_APP
can point to local packages that are not installed in editable mode, althoughpip install -e
is still preferred. #2414The
View
class attributeprovide_automatic_options
is set inas_view()
, to be detected byadd_url_rule()
. #2316Error handling will try handlers registered for
blueprint, code
,app, code
,blueprint, exception
,app, exception
. #2314Cookie
is added to the response’sVary
header if the session is accessed at all during the request (and not deleted). #2288test_request_context()
acceptssubdomain
andurl_scheme
arguments for use when building the base URL. #1621Set
APPLICATION_ROOT
to'/'
by default. This was already the implicit default when it was set toNone
.TRAP_BAD_REQUEST_ERRORS
is enabled by default in debug mode.BadRequestKeyError
has a message with the bad key in debug mode instead of the generic bad request message. #2348Allow registering new tags with
TaggedJSONSerializer
to support storing other types in the session cookie. #2352Only open the session if the request has not been pushed onto the context stack yet. This allows
stream_with_context()
generators to access the same session that the containing view uses. #2354Add
json
keyword argument for the test client request methods. This will dump the given object as JSON and set the appropriate content type. #2358Extract JSON handling to a mixin applied to both the
Request
andResponse
classes. This adds theis_json()
andget_json()
methods to the response to make testing JSON response much easier. #2358Removed error handler caching because it caused unexpected results for some exception inheritance hierarchies. Register handlers explicitly for each exception if you want to avoid traversing the MRO. #2362
Fix incorrect JSON encoding of aware, non-UTC datetimes. #2374
Template auto reloading will honor debug mode even even if
jinja_env
was already accessed. #2373The following old deprecated code was removed. #2385
flask.ext
- import extensions directly by their name instead of through theflask.ext
namespace. For example,import flask.ext.sqlalchemy
becomesimport flask_sqlalchemy
.Flask.init_jinja_globals
- extendFlask.create_jinja_environment()
instead.Flask.error_handlers
- tracked byFlask.error_handler_spec
, useFlask.errorhandler()
to register handlers.Flask.request_globals_class
- useFlask.app_ctx_globals_class
instead.Flask.static_path
- useFlask.static_url_path
instead.Request.module
- useRequest.blueprint
instead.
The
Request.json
property is no longer deprecated. #1421Support passing a
EnvironBuilder
ordict
totest_client.open
. #2412The
flask
command andFlask.run()
will load environment variables from.env
and.flaskenv
files if python-dotenv is installed. #2416When passing a full URL to the test client, the scheme in the URL is used instead of
PREFERRED_URL_SCHEME
. #2430Flask.logger
has been simplified.LOGGER_NAME
andLOGGER_HANDLER_POLICY
config was removed. The logger is always namedflask.app
. The level is only set on first access, it doesn’t checkFlask.debug
each time. Only one format is used, not different ones depending onFlask.debug
. No handlers are removed, and a handler is only added if no handlers are already configured. #2436Blueprint view function names may not contain dots. #2450
Fix a
ValueError
caused by invalidRange
requests in some cases. #2526The development server uses threads by default. #2529
Loading config files with
silent=True
will ignoreENOTDIR
errors. #2581Pass
--cert
and--key
options toflask run
to run the development server over HTTPS. #2606Added
SESSION_COOKIE_SAMESITE
to control theSameSite
attribute on the session cookie. #2607Added
test_cli_runner()
to create a Click runner that can invoke Flask CLI commands for testing. #2636Subdomain matching is disabled by default and setting
SERVER_NAME
does not implicitly enable it. It can be enabled by passingsubdomain_matching=True
to theFlask
constructor. #2635A single trailing slash is stripped from the blueprint
url_prefix
when it is registered with the app. #2629Request.get_json()
doesn’t cache the result if parsing fails whensilent
is true. #2651Request.get_json()
no longer accepts arbitrary encodings. Incoming JSON should be encoded using UTF-8 per RFC 8259, but Flask will autodetect UTF-8, -16, or -32. #2691Added
MAX_COOKIE_SIZE
andResponse.max_cookie_size
to control when Werkzeug warns about large cookies that browsers may ignore. #2693Updated documentation theme to make docs look better in small windows. #2709
Rewrote the tutorial docs and example project to take a more structured approach to help new users avoid common pitfalls. #2676
Version 0.12.3¶
Released 2018-04-26
Request.get_json()
no longer accepts arbitrary encodings. Incoming JSON should be encoded using UTF-8 per RFC 8259, but Flask will autodetect UTF-8, -16, or -32. #2692Fix a Python warning about imports when using
python -m flask
. #2666Fix a
ValueError
caused by invalidRange
requests in some cases.
Version 0.12.1¶
Released 2017-03-31
Prevent
flask run
from showing aNoAppException
when anImportError
occurs within the imported application module.Fix encoding behavior of
app.config.from_pyfile
for Python 3. #2118Use the
SERVER_NAME
config if it is present as default values forapp.run
. #2109, #2152Call
ctx.auto_pop
with the exception object instead ofNone
, in the event that aBaseException
such asKeyboardInterrupt
is raised in a request handler.
Version 0.12¶
Released 2016-12-21, codename Punsch
The cli command now responds to
--version
.Mimetype guessing and ETag generation for file-like objects in
send_file
has been removed. #104, :pr`1849`Mimetype guessing in
send_file
now fails loudly and doesn’t fall back toapplication/octet-stream
. #1988Make
flask.safe_join
able to join multiple paths likeos.path.join
#1730Revert a behavior change that made the dev server crash instead of returning an Internal Server Error. #2006
Correctly invoke response handlers for both regular request dispatching as well as error handlers.
Disable logger propagation by default for the app logger.
Add support for range requests in
send_file
.app.test_client
includes preset default environment, which can now be directly set, instead of perclient.get
.Fix crash when running under PyPy3. #1814
Version 0.11.1¶
Released 2016-06-07
Fixed a bug that prevented
FLASK_APP=foobar/__init__.py
from working. #1872
Version 0.11¶
Released 2016-05-29, codename Absinthe
Added support to serializing top-level arrays to
flask.jsonify()
. This introduces a security risk in ancient browsers.Added before_render_template signal.
Added
**kwargs
toflask.Test.test_client()
to support passing additional keyword arguments to the constructor offlask.Flask.test_client_class
.Added
SESSION_REFRESH_EACH_REQUEST
config key that controls the set-cookie behavior. If set toTrue
a permanent session will be refreshed each request and get their lifetime extended, if set toFalse
it will only be modified if the session actually modifies. Non permanent sessions are not affected by this and will always expire if the browser window closes.Made Flask support custom JSON mimetypes for incoming data.
Added support for returning tuples in the form
(response, headers)
from a view function.Added
flask.Config.from_json()
.Added
flask.Flask.config_class
.Added
flask.Config.get_namespace()
.Templates are no longer automatically reloaded outside of debug mode. This can be configured with the new
TEMPLATES_AUTO_RELOAD
config key.Added a workaround for a limitation in Python 3.3’s namespace loader.
Added support for explicit root paths when using Python 3.3’s namespace packages.
Added flask and the
flask.cli
module to start the local debug server through the click CLI system. This is recommended over the oldflask.run()
method as it works faster and more reliable due to a different design and also replacesFlask-Script
.Error handlers that match specific classes are now checked first, thereby allowing catching exceptions that are subclasses of HTTP exceptions (in
werkzeug.exceptions
). This makes it possible for an extension author to create exceptions that will by default result in the HTTP error of their choosing, but may be caught with a custom error handler if desired.Added
flask.Config.from_mapping()
.Flask will now log by default even if debug is disabled. The log format is now hardcoded but the default log handling can be disabled through the
LOGGER_HANDLER_POLICY
configuration key.Removed deprecated module functionality.
Added the
EXPLAIN_TEMPLATE_LOADING
config flag which when enabled will instruct Flask to explain how it locates templates. This should help users debug when the wrong templates are loaded.Enforce blueprint handling in the order they were registered for template loading.
Ported test suite to py.test.
Deprecated
request.json
in favour ofrequest.get_json()
.Add “pretty” and “compressed” separators definitions in jsonify() method. Reduces JSON response size when
JSONIFY_PRETTYPRINT_REGULAR=False
by removing unnecessary white space included by default after separators.JSON responses are now terminated with a newline character, because it is a convention that UNIX text files end with a newline and some clients don’t deal well when this newline is missing. This came up originally as a part of https://github.com/postmanlabs/httpbin/issues/168. #1262
The automatically provided
OPTIONS
method is now correctly disabled if the user registered an overriding rule with the lowercase-versionoptions
. #1288flask.json.jsonify
now supports thedatetime.date
type. #1326Don’t leak exception info of already caught exceptions to context teardown handlers. #1393
Allow custom Jinja environment subclasses. #1422
Updated extension dev guidelines.
flask.g
now haspop()
andsetdefault
methods.Turn on autoescape for
flask.templating.render_template_string
by default. #1515flask.ext
is now deprecated. #1484send_from_directory
now raises BadRequest if the filename is invalid on the server OS. #1763Added the
JSONIFY_MIMETYPE
configuration variable. #1728Exceptions during teardown handling will no longer leave bad application contexts lingering around.
Fixed broken
test_appcontext_signals()
test case.Raise an
AttributeError
inflask.helpers.find_package()
with a useful message explaining why it is raised when a PEP 302 import hook is used without anis_package()
method.Fixed an issue causing exceptions raised before entering a request or app context to be passed to teardown handlers.
Fixed an issue with query parameters getting removed from requests in the test client when absolute URLs were requested.
Made
@before_first_request
into a decorator as intended.Fixed an etags bug when sending a file streams with a name.
Fixed
send_from_directory
not expanding to the application root path correctly.Changed logic of before first request handlers to flip the flag after invoking. This will allow some uses that are potentially dangerous but should probably be permitted.
Fixed Python 3 bug when a handler from
app.url_build_error_handlers
reraises theBuildError
.
Version 0.10.1¶
Released 2013-06-14
Fixed an issue where
|tojson
was not quoting single quotes which made the filter not work properly in HTML attributes. Now it’s possible to use that filter in single quoted attributes. This should make using that filter with angular.js easier.Added support for byte strings back to the session system. This broke compatibility with the common case of people putting binary data for token verification into the session.
Fixed an issue where registering the same method twice for the same endpoint would trigger an exception incorrectly.
Version 0.10¶
Released 2013-06-13, codename Limoncello
Changed default cookie serialization format from pickle to JSON to limit the impact an attacker can do if the secret key leaks.
Added
template_test
methods in addition to the already existingtemplate_filter
method family.Added
template_global
methods in addition to the already existingtemplate_filter
method family.Set the content-length header for x-sendfile.
tojson
filter now does not escape script blocks in HTML5 parsers.tojson
used in templates is now safe by default due. This was allowed due to the different escaping behavior.Flask will now raise an error if you attempt to register a new function on an already used endpoint.
Added wrapper module around simplejson and added default serialization of datetime objects. This allows much easier customization of how JSON is handled by Flask or any Flask extension.
Removed deprecated internal
flask.session
module alias. Useflask.sessions
instead to get the session module. This is not to be confused withflask.session
the session proxy.Templates can now be rendered without request context. The behavior is slightly different as the
request
,session
andg
objects will not be available and blueprint’s context processors are not called.The config object is now available to the template as a real global and not through a context processor which makes it available even in imported templates by default.
Added an option to generate non-ascii encoded JSON which should result in less bytes being transmitted over the network. It’s disabled by default to not cause confusion with existing libraries that might expect
flask.json.dumps
to return bytes by default.flask.g
is now stored on the app context instead of the request context.flask.g
now gained aget()
method for not erroring out on non existing items.flask.g
now can be used with thein
operator to see what’s defined and it now is iterable and will yield all attributes stored.flask.Flask.request_globals_class
got renamed toflask.Flask.app_ctx_globals_class
which is a better name to what it does since 0.10.request
,session
andg
are now also added as proxies to the template context which makes them available in imported templates. One has to be very careful with those though because usage outside of macros might cause caching.Flask will no longer invoke the wrong error handlers if a proxy exception is passed through.
Added a workaround for chrome’s cookies in localhost not working as intended with domain names.
Changed logic for picking defaults for cookie values from sessions to work better with Google Chrome.
Added
message_flashed
signal that simplifies flashing testing.Added support for copying of request contexts for better working with greenlets.
Removed custom JSON HTTP exception subclasses. If you were relying on them you can reintroduce them again yourself trivially. Using them however is strongly discouraged as the interface was flawed.
Python requirements changed: requiring Python 2.6 or 2.7 now to prepare for Python 3.3 port.
Changed how the teardown system is informed about exceptions. This is now more reliable in case something handles an exception halfway through the error handling process.
Request context preservation in debug mode now keeps the exception information around which means that teardown handlers are able to distinguish error from success cases.
Added the
JSONIFY_PRETTYPRINT_REGULAR
configuration variable.Flask now orders JSON keys by default to not trash HTTP caches due to different hash seeds between different workers.
Added
appcontext_pushed
andappcontext_popped
signals.The builtin run method now takes the
SERVER_NAME
into account when picking the default port to run on.Added
flask.request.get_json()
as a replacement for the oldflask.request.json
property.
Version 0.9¶
Released 2012-07-01, codename Campari
The
flask.Request.on_json_loading_failed()
now returns a JSON formatted response by default.The
flask.url_for()
function now can generate anchors to the generated links.The
flask.url_for()
function now can also explicitly generate URL rules specific to a given HTTP method.Logger now only returns the debug log setting if it was not set explicitly.
Unregister a circular dependency between the WSGI environment and the request object when shutting down the request. This means that environ
werkzeug.request
will beNone
after the response was returned to the WSGI server but has the advantage that the garbage collector is not needed on CPython to tear down the request unless the user created circular dependencies themselves.Session is now stored after callbacks so that if the session payload is stored in the session you can still modify it in an after request callback.
The
flask.Flask
class will avoid importing the provided import name if it can (the required first parameter), to benefit tools which build Flask instances programmatically. The Flask class will fall back to using import on systems with custom module hooks, e.g. Google App Engine, or when the import name is inside a zip archive (usually a .egg) prior to Python 2.7.Blueprints now have a decorator to add custom template filters application wide,
flask.Blueprint.app_template_filter()
.The Flask and Blueprint classes now have a non-decorator method for adding custom template filters application wide,
flask.Flask.add_template_filter()
andflask.Blueprint.add_app_template_filter()
.The
flask.get_flashed_messages()
function now allows rendering flashed message categories in separate blocks, through acategory_filter
argument.The
flask.Flask.run()
method now acceptsNone
forhost
andport
arguments, using default values whenNone
. This allows for calling run using configuration values, e.g.app.run(app.config.get('MYHOST'), app.config.get('MYPORT'))
, with proper behavior whether or not a config file is provided.The
flask.render_template()
method now accepts a either an iterable of template names or a single template name. Previously, it only accepted a single template name. On an iterable, the first template found is rendered.Added
flask.Flask.app_context()
which works very similar to the request context but only provides access to the current application. This also adds support for URL generation without an active request context.View functions can now return a tuple with the first instance being an instance of
flask.Response
. This allows for returningjsonify(error="error msg"), 400
from a view function.Flask
andBlueprint
now provide aget_send_file_max_age()
hook for subclasses to override behavior of serving static files from Flask when usingflask.Flask.send_static_file()
(used for the default static file handler) andsend_file()
. This hook is provided a filename, which for example allows changing cache controls by file extension. The default max-age forsend_file
and static files can be configured through a newSEND_FILE_MAX_AGE_DEFAULT
configuration variable, which is used in the defaultget_send_file_max_age
implementation.Fixed an assumption in sessions implementation which could break message flashing on sessions implementations which use external storage.
Changed the behavior of tuple return values from functions. They are no longer arguments to the response object, they now have a defined meaning.
Added
flask.Flask.request_globals_class
to allow a specific class to be used on creation of theg
instance of each request.Added
required_methods
attribute to view functions to force-add methods on registration.Added
flask.after_this_request()
.Added
flask.stream_with_context()
and the ability to push contexts multiple times without producing unexpected behavior.
Version 0.8.1¶
Released 2012-07-01
Fixed an issue with the undocumented
flask.session
module to not work properly on Python 2.5. It should not be used but did cause some problems for package managers.
Version 0.8¶
Released 2011-09-29, codename Rakija
Refactored session support into a session interface so that the implementation of the sessions can be changed without having to override the Flask class.
Empty session cookies are now deleted properly automatically.
View functions can now opt out of getting the automatic OPTIONS implementation.
HTTP exceptions and Bad Request errors can now be trapped so that they show up normally in the traceback.
Flask in debug mode is now detecting some common problems and tries to warn you about them.
Flask in debug mode will now complain with an assertion error if a view was attached after the first request was handled. This gives earlier feedback when users forget to import view code ahead of time.
Added the ability to register callbacks that are only triggered once at the beginning of the first request. (
Flask.before_first_request()
)Malformed JSON data will now trigger a bad request HTTP exception instead of a value error which usually would result in a 500 internal server error if not handled. This is a backwards incompatible change.
Applications now not only have a root path where the resources and modules are located but also an instance path which is the designated place to drop files that are modified at runtime (uploads etc.). Also this is conceptually only instance depending and outside version control so it’s the perfect place to put configuration files etc.
Added the
APPLICATION_ROOT
configuration variable.Implemented
session_transaction()
to easily modify sessions from the test environment.Refactored test client internally. The
APPLICATION_ROOT
configuration variable as well asSERVER_NAME
are now properly used by the test client as defaults.Added
flask.views.View.decorators
to support simpler decorating of pluggable (class-based) views.Fixed an issue where the test client if used with the “with” statement did not trigger the execution of the teardown handlers.
Added finer control over the session cookie parameters.
HEAD requests to a method view now automatically dispatch to the
get
method if no handler was implemented.Implemented the virtual
flask.ext
package to import extensions from.The context preservation on exceptions is now an integral component of Flask itself and no longer of the test client. This cleaned up some internal logic and lowers the odds of runaway request contexts in unittests.
Fixed the Jinja2 environment’s
list_templates
method not returning the correct names when blueprints or modules were involved.
Version 0.7.2¶
Released 2011-07-06
Fixed an issue with URL processors not properly working on blueprints.
Version 0.7.1¶
Released 2011-06-29
Added missing future import that broke 2.5 compatibility.
Fixed an infinite redirect issue with blueprints.
Version 0.7¶
Released 2011-06-28, codename Grappa
Added
make_default_options_response()
which can be used by subclasses to alter the default behavior forOPTIONS
responses.Unbound locals now raise a proper
RuntimeError
instead of anAttributeError
.Mimetype guessing and etag support based on file objects is now deprecated for
flask.send_file()
because it was unreliable. Pass filenames instead or attach your own etags and provide a proper mimetype by hand.Static file handling for modules now requires the name of the static folder to be supplied explicitly. The previous autodetection was not reliable and caused issues on Google’s App Engine. Until 1.0 the old behavior will continue to work but issue dependency warnings.
Fixed a problem for Flask to run on jython.
Added a
PROPAGATE_EXCEPTIONS
configuration variable that can be used to flip the setting of exception propagation which previously was linked toDEBUG
alone and is now linked to eitherDEBUG
orTESTING
.Flask no longer internally depends on rules being added through the
add_url_rule
function and can now also accept regular werkzeug rules added to the url map.Added an
endpoint
method to the flask application object which allows one to register a callback to an arbitrary endpoint with a decorator.Use Last-Modified for static file sending instead of Date which was incorrectly introduced in 0.6.
Added
create_jinja_loader
to override the loader creation process.Implemented a silent flag for
config.from_pyfile
.Added
teardown_request
decorator, for functions that should run at the end of a request regardless of whether an exception occurred. Also the behavior forafter_request
was changed. It’s now no longer executed when an exception is raised.Implemented
flask.has_request_context()
Deprecated
init_jinja_globals
. Override thecreate_jinja_environment()
method instead to achieve the same functionality.Added
flask.safe_join()
The automatic JSON request data unpacking now looks at the charset mimetype parameter.
Don’t modify the session on
flask.get_flashed_messages()
if there are no messages in the session.before_request
handlers are now able to abort requests with errors.It is not possible to define user exception handlers. That way you can provide custom error messages from a central hub for certain errors that might occur during request processing (for instance database connection errors, timeouts from remote resources etc.).
Blueprints can provide blueprint specific error handlers.
Implemented generic class-based views.
Version 0.6.1¶
Released 2010-12-31
Fixed an issue where the default
OPTIONS
response was not exposing all valid methods in theAllow
header.Jinja2 template loading syntax now allows “./” in front of a template load path. Previously this caused issues with module setups.
Fixed an issue where the subdomain setting for modules was ignored for the static folder.
Fixed a security problem that allowed clients to download arbitrary files if the host server was a windows based operating system and the client uses backslashes to escape the directory the files where exposed from.
Version 0.6¶
Released 2010-07-27, codename Whisky
After request functions are now called in reverse order of registration.
OPTIONS is now automatically implemented by Flask unless the application explicitly adds ‘OPTIONS’ as method to the URL rule. In this case no automatic OPTIONS handling kicks in.
Static rules are now even in place if there is no static folder for the module. This was implemented to aid GAE which will remove the static folder if it’s part of a mapping in the .yml file.
The
config
is now available in the templates asconfig
.Context processors will no longer override values passed directly to the render function.
Added the ability to limit the incoming request data with the new
MAX_CONTENT_LENGTH
configuration value.The endpoint for the
flask.Module.add_url_rule()
method is now optional to be consistent with the function of the same name on the application object.Added a
flask.make_response()
function that simplifies creating response object instances in views.Added signalling support based on blinker. This feature is currently optional and supposed to be used by extensions and applications. If you want to use it, make sure to have blinker installed.
Refactored the way URL adapters are created. This process is now fully customizable with the
create_url_adapter()
method.Modules can now register for a subdomain instead of just an URL prefix. This makes it possible to bind a whole module to a configurable subdomain.
Version 0.5.2¶
Released 2010-07-15
Fixed another issue with loading templates from directories when modules were used.
Version 0.5.1¶
Released 2010-07-06
Fixes an issue with template loading from directories when modules where used.
Version 0.5¶
Released 2010-07-06, codename Calvados
Fixed a bug with subdomains that was caused by the inability to specify the server name. The server name can now be set with the
SERVER_NAME
config key. This key is now also used to set the session cookie cross-subdomain wide.Autoescaping is no longer active for all templates. Instead it is only active for
.html
,.htm
,.xml
and.xhtml
. Inside templates this behavior can be changed with theautoescape
tag.Refactored Flask internally. It now consists of more than a single file.
flask.send_file()
now emits etags and has the ability to do conditional responses builtin.(temporarily) dropped support for zipped applications. This was a rarely used feature and led to some confusing behavior.
Added support for per-package template and static-file directories.
Removed support for
create_jinja_loader
which is no longer used in 0.5 due to the improved module support.Added a helper function to expose files from any directory.
Version 0.4¶
Released 2010-06-18, codename Rakia
Added the ability to register application wide error handlers from modules.
after_request()
handlers are now also invoked if the request dies with an exception and an error handling page kicks in.Test client has not the ability to preserve the request context for a little longer. This can also be used to trigger custom requests that do not pop the request stack for testing.
Because the Python standard library caches loggers, the name of the logger is configurable now to better support unittests.
Added
TESTING
switch that can activate unittesting helpers.The logger switches to
DEBUG
mode now if debug is enabled.
Version 0.3.1¶
Released 2010-05-28
Fixed a error reporting bug with
flask.Config.from_envvar()
Removed some unused code from flask
Release does no longer include development leftover files (.git folder for themes, built documentation in zip and pdf file and some .pyc files)
Version 0.3¶
Released 2010-05-28, codename Schnaps
Added support for categories for flashed messages.
The application now configures a
logging.Handler
and will log request handling exceptions to that logger when not in debug mode. This makes it possible to receive mails on server errors for example.Added support for context binding that does not require the use of the with statement for playing in the console.
The request context is now available within the with statement making it possible to further push the request context or pop it.
Added support for configurations.
Version 0.2¶
Released 2010-05-12, codename J?germeister
Various bugfixes
Integrated JSON support
Added
get_template_attribute()
helper function.add_url_rule()
can now also register a view function.Refactored internal request dispatching.
Server listens on 127.0.0.1 by default now to fix issues with chrome.
Added external URL support.
Added support for
send_file()
Module support and internal request handling refactoring to better support pluggable applications.
Sessions can be set to be permanent now on a per-session basis.
Better error reporting on missing secret keys.
Added support for Google Appengine.