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Merge branch 'master' into reload_templates_run_debug

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David Lord 2017-06-14 09:58:33 -07:00
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flask/app.py
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@ -10,31 +10,32 @@
"""
import os
import sys
from threading import Lock
import warnings
from datetime import timedelta
from itertools import chain
from functools import update_wrapper
from collections import deque
from itertools import chain
from threading import Lock
from werkzeug.datastructures import ImmutableDict
from werkzeug.routing import Map, Rule, RequestRedirect, BuildError
from werkzeug.exceptions import HTTPException, InternalServerError, \
MethodNotAllowed, BadRequest, default_exceptions
from werkzeug.datastructures import ImmutableDict, Headers
from werkzeug.exceptions import BadRequest, HTTPException, \
InternalServerError, MethodNotAllowed, default_exceptions, \
BadRequestKeyError
from werkzeug.routing import BuildError, Map, RequestRedirect, Rule
from .helpers import _PackageBoundObject, url_for, get_flashed_messages, \
locked_cached_property, _endpoint_from_view_func, find_package, \
get_debug_flag
from . import json, cli
from .wrappers import Request, Response
from .config import ConfigAttribute, Config
from .ctx import RequestContext, AppContext, _AppCtxGlobals
from .globals import _request_ctx_stack, request, session, g
from . import cli, json
from ._compat import integer_types, reraise, string_types, text_type
from .config import Config, ConfigAttribute
from .ctx import AppContext, RequestContext, _AppCtxGlobals
from .globals import _request_ctx_stack, g, request, session
from .helpers import _PackageBoundObject, \
_endpoint_from_view_func, find_package, get_debug_flag, \
get_flashed_messages, locked_cached_property, url_for
from .sessions import SecureCookieSessionInterface
from .signals import appcontext_tearing_down, got_request_exception, \
request_finished, request_started, request_tearing_down
from .templating import DispatchingJinjaLoader, Environment, \
_default_template_ctx_processor
from .signals import request_started, request_finished, got_request_exception, \
request_tearing_down, appcontext_tearing_down
from ._compat import reraise, string_types, text_type, integer_types
_default_template_ctx_processor
from .wrappers import Request, Response
# a lock used for logger initialization
_logger_lock = Lock()
@ -124,6 +125,9 @@ class Flask(_PackageBoundObject):
.. versionadded:: 0.11
The `root_path` parameter was added.
.. versionadded:: 0.13
The `host_matching` and `static_host` parameters were added.
:param import_name: the name of the application package
:param static_url_path: can be used to specify a different path for the
static files on the web. Defaults to the name
@ -131,6 +135,11 @@ class Flask(_PackageBoundObject):
:param static_folder: the folder with static files that should be served
at `static_url_path`. Defaults to the ``'static'``
folder in the root path of the application.
:param host_matching: sets the app's ``url_map.host_matching`` to the given
value. Defaults to False.
:param static_host: the host to use when adding the static route. Defaults
to None. Required when using ``host_matching=True``
with a ``static_folder`` configured.
:param template_folder: the folder that contains the templates that should
be used by the application. Defaults to
``'templates'`` folder in the root path of the
@ -213,7 +222,7 @@ class Flask(_PackageBoundObject):
#: The testing flag. Set this to ``True`` to enable the test mode of
#: Flask extensions (and in the future probably also Flask itself).
#: For example this might activate unittest helpers that have an
#: For example this might activate test helpers that have an
#: additional runtime cost which should not be enabled by default.
#:
#: If this is enabled and PROPAGATE_EXCEPTIONS is not changed from the
@ -300,7 +309,7 @@ class Flask(_PackageBoundObject):
'LOGGER_NAME': None,
'LOGGER_HANDLER_POLICY': 'always',
'SERVER_NAME': None,
'APPLICATION_ROOT': None,
'APPLICATION_ROOT': '/',
'SESSION_COOKIE_NAME': 'session',
'SESSION_COOKIE_DOMAIN': None,
'SESSION_COOKIE_PATH': None,
@ -309,13 +318,13 @@ class Flask(_PackageBoundObject):
'SESSION_REFRESH_EACH_REQUEST': True,
'MAX_CONTENT_LENGTH': None,
'SEND_FILE_MAX_AGE_DEFAULT': timedelta(hours=12),
'TRAP_BAD_REQUEST_ERRORS': False,
'TRAP_BAD_REQUEST_ERRORS': None,
'TRAP_HTTP_EXCEPTIONS': False,
'EXPLAIN_TEMPLATE_LOADING': False,
'PREFERRED_URL_SCHEME': 'http',
'JSON_AS_ASCII': True,
'JSON_SORT_KEYS': True,
'JSONIFY_PRETTYPRINT_REGULAR': True,
'JSONIFY_PRETTYPRINT_REGULAR': False,
'JSONIFY_MIMETYPE': 'application/json',
'TEMPLATES_AUTO_RELOAD': None,
})
@ -337,8 +346,24 @@ class Flask(_PackageBoundObject):
#: .. versionadded:: 0.8
session_interface = SecureCookieSessionInterface()
# TODO remove the next three attrs when Sphinx :inherited-members: works
# https://github.com/sphinx-doc/sphinx/issues/741
#: The name of the package or module that this app belongs to. Do not
#: change this once it is set by the constructor.
import_name = None
#: Location of the template files to be added to the template lookup.
#: ``None`` if templates should not be added.
template_folder = None
#: Absolute path to the package on the filesystem. Used to look up
#: resources contained in the package.
root_path = None
def __init__(self, import_name, static_path=None, static_url_path=None,
static_folder='static', template_folder='templates',
static_folder='static', static_host=None,
host_matching=False, template_folder='templates',
instance_path=None, instance_relative_config=False,
root_path=None):
_PackageBoundObject.__init__(self, import_name,
@ -392,7 +417,7 @@ class Flask(_PackageBoundObject):
#: is the class for the instance check and the second the error handler
#: function.
#:
#: To register a error handler, use the :meth:`errorhandler`
#: To register an error handler, use the :meth:`errorhandler`
#: decorator.
self.error_handler_spec = {None: self._error_handlers}
@ -405,17 +430,16 @@ class Flask(_PackageBoundObject):
#: .. versionadded:: 0.9
self.url_build_error_handlers = []
#: A dictionary with lists of functions that should be called at the
#: beginning of the request. The key of the dictionary is the name of
#: the blueprint this function is active for, ``None`` for all requests.
#: This can for example be used to open database connections or
#: getting hold of the currently logged in user. To register a
#: function here, use the :meth:`before_request` decorator.
#: A dictionary with lists of functions that will be called at the
#: beginning of each request. The key of the dictionary is the name of
#: the blueprint this function is active for, or ``None`` for all
#: requests. To register a function, use the :meth:`before_request`
#: decorator.
self.before_request_funcs = {}
#: A lists of functions that should be called at the beginning of the
#: first request to this instance. To register a function here, use
#: the :meth:`before_first_request` decorator.
#: A list of functions that will be called at the beginning of the
#: first request to this instance. To register a function, use the
#: :meth:`before_first_request` decorator.
#:
#: .. versionadded:: 0.8
self.before_first_request_funcs = []
@ -447,12 +471,11 @@ class Flask(_PackageBoundObject):
#: .. versionadded:: 0.9
self.teardown_appcontext_funcs = []
#: A dictionary with lists of functions that can be used as URL
#: value processor functions. Whenever a URL is built these functions
#: are called to modify the dictionary of values in place. The key
#: ``None`` here is used for application wide
#: callbacks, otherwise the key is the name of the blueprint.
#: Each of these functions has the chance to modify the dictionary
#: A dictionary with lists of functions that are called before the
#: :attr:`before_request_funcs` functions. The key of the dictionary is
#: the name of the blueprint this function is active for, or ``None``
#: for all requests. To register a function, use
#: :meth:`url_value_preprocessor`.
#:
#: .. versionadded:: 0.7
self.url_value_preprocessors = {}
@ -519,26 +542,29 @@ class Flask(_PackageBoundObject):
#: def to_python(self, value):
#: return value.split(',')
#: def to_url(self, values):
#: return ','.join(BaseConverter.to_url(value)
#: return ','.join(super(ListConverter, self).to_url(value)
#: for value in values)
#:
#: app = Flask(__name__)
#: app.url_map.converters['list'] = ListConverter
self.url_map = Map()
self.url_map.host_matching = host_matching
# tracks internally if the application already handled at least one
# request.
self._got_first_request = False
self._before_request_lock = Lock()
# register the static folder for the application. Do that even
# if the folder does not exist. First of all it might be created
# while the server is running (usually happens during development)
# but also because google appengine stores static files somewhere
# else when mapped with the .yml file.
# Add a static route using the provided static_url_path, static_host,
# and static_folder if there is a configured static_folder.
# Note we do this without checking if static_folder exists.
# For one, it might be created while the server is running (e.g. during
# development). Also, Google App Engine stores static files somewhere
if self.has_static_folder:
assert bool(static_host) == host_matching, 'Invalid static_host/host_matching combination'
self.add_url_rule(self.static_url_path + '/<path:filename>',
endpoint='static',
endpoint='static', host=static_host,
view_func=self.send_static_file)
#: The click command line context for this application. Commands
@ -814,7 +840,8 @@ class Flask(_PackageBoundObject):
:param host: the hostname to listen on. Set this to ``'0.0.0.0'`` to
have the server available externally as well. Defaults to
``'127.0.0.1'``.
``'127.0.0.1'`` or the host in the ``SERVER_NAME`` config
variable if present.
:param port: the port of the webserver. Defaults to ``5000`` or the
port defined in the ``SERVER_NAME`` config variable if
present.
@ -825,27 +852,33 @@ class Flask(_PackageBoundObject):
:func:`werkzeug.serving.run_simple` for more
information.
"""
# Change this into a no-op if the server is invoked from the
# command line. Have a look at cli.py for more information.
if os.environ.get('FLASK_RUN_FROM_CLI_SERVER') == '1':
from .debughelpers import explain_ignored_app_run
explain_ignored_app_run()
return
from werkzeug.serving import run_simple
if host is None:
host = '127.0.0.1'
if port is None:
server_name = self.config['SERVER_NAME']
if server_name and ':' in server_name:
port = int(server_name.rsplit(':', 1)[1])
else:
port = 5000
_host = '127.0.0.1'
_port = 5000
server_name = self.config.get("SERVER_NAME")
sn_host, sn_port = None, None
if server_name:
sn_host, _, sn_port = server_name.partition(':')
host = host or sn_host or _host
port = int(port or sn_port or _port)
if debug is not None:
self.debug = bool(debug)
options.setdefault('use_reloader', self.debug)
options.setdefault('use_debugger', self.debug)
options.setdefault('passthrough_errors', True)
if debug:
self.jinja_env.auto_reload = True
try:
run_simple(host, port, self, **options)
finally:
# reset the first request information if the development server
# resetted normally. This makes it possible to restart the server
# reset normally. This makes it possible to restart the server
# without reloader and that stuff from an interactive shell.
self._got_first_request = False
@ -879,9 +912,9 @@ class Flask(_PackageBoundObject):
from flask.testing import FlaskClient
class CustomClient(FlaskClient):
def __init__(self, authentication=None, *args, **kwargs):
FlaskClient.__init__(*args, **kwargs)
self._authentication = authentication
def __init__(self, *args, **kwargs):
self._authentication = kwargs.pop("authentication")
super(CustomClient,self).__init__( *args, **kwargs)
app.test_client_class = CustomClient
client = app.test_client(authentication='Basic ....')
@ -911,8 +944,17 @@ class Flask(_PackageBoundObject):
:attr:`secret_key` is set. Instead of overriding this method
we recommend replacing the :class:`session_interface`.
.. deprecated: 1.0
Will be removed in 1.1. Use ``session_interface.open_session``
instead.
:param request: an instance of :attr:`request_class`.
"""
warnings.warn(DeprecationWarning(
'"open_session" is deprecated and will be removed in 1.1. Use'
' "session_interface.open_session" instead.'
))
return self.session_interface.open_session(self, request)
def save_session(self, session, response):
@ -920,53 +962,74 @@ class Flask(_PackageBoundObject):
implementation, check :meth:`open_session`. Instead of overriding this
method we recommend replacing the :class:`session_interface`.
.. deprecated: 1.0
Will be removed in 1.1. Use ``session_interface.save_session``
instead.
:param session: the session to be saved (a
:class:`~werkzeug.contrib.securecookie.SecureCookie`
object)
:param response: an instance of :attr:`response_class`
"""
warnings.warn(DeprecationWarning(
'"save_session" is deprecated and will be removed in 1.1. Use'
' "session_interface.save_session" instead.'
))
return self.session_interface.save_session(self, session, response)
def make_null_session(self):
"""Creates a new instance of a missing session. Instead of overriding
this method we recommend replacing the :class:`session_interface`.
.. deprecated: 1.0
Will be removed in 1.1. Use ``session_interface.make_null_session``
instead.
.. versionadded:: 0.7
"""
warnings.warn(DeprecationWarning(
'"make_null_session" is deprecated and will be removed in 1.1. Use'
' "session_interface.make_null_session" instead.'
))
return self.session_interface.make_null_session(self)
@setupmethod
def register_blueprint(self, blueprint, **options):
"""Register a blueprint on the application. For information about
blueprints head over to :ref:`blueprints`.
"""Register a :class:`~flask.Blueprint` on the application. Keyword
arguments passed to this method will override the defaults set on the
blueprint.
The blueprint name is passed in as the first argument.
Options are passed as additional keyword arguments and forwarded to
`blueprints` in an "options" dictionary.
Calls the blueprint's :meth:`~flask.Blueprint.register` method after
recording the blueprint in the application's :attr:`blueprints`.
:param subdomain: set a subdomain for the blueprint
:param url_prefix: set the prefix for all URLs defined on the blueprint.
``(url_prefix='/<lang code>')``
:param url_defaults: a dictionary with URL defaults that is added to
each and every URL defined with this blueprint
:param static_folder: add a static folder to urls in this blueprint
:param static_url_path: add a static url path to urls in this blueprint
:param template_folder: set an alternate template folder
:param root_path: set an alternate root path for this blueprint
:param blueprint: The blueprint to register.
:param url_prefix: Blueprint routes will be prefixed with this.
:param subdomain: Blueprint routes will match on this subdomain.
:param url_defaults: Blueprint routes will use these default values for
view arguments.
:param options: Additional keyword arguments are passed to
:class:`~flask.blueprints.BlueprintSetupState`. They can be
accessed in :meth:`~flask.Blueprint.record` callbacks.
.. versionadded:: 0.7
"""
first_registration = False
if blueprint.name in self.blueprints:
assert self.blueprints[blueprint.name] is blueprint, \
'A blueprint\'s name collision occurred between %r and ' \
'%r. Both share the same name "%s". Blueprints that ' \
'are created on the fly need unique names.' % \
(blueprint, self.blueprints[blueprint.name], blueprint.name)
assert self.blueprints[blueprint.name] is blueprint, (
'A name collision occurred between blueprints %r and %r. Both'
' share the same name "%s". Blueprints that are created on the'
' fly need unique names.' % (
blueprint, self.blueprints[blueprint.name], blueprint.name
)
)
else:
self.blueprints[blueprint.name] = blueprint
self._blueprint_order.append(blueprint)
first_registration = True
blueprint.register(self, options, first_registration)
def iter_blueprints(self):
@ -977,7 +1040,7 @@ class Flask(_PackageBoundObject):
return iter(self._blueprint_order)
@setupmethod
def add_url_rule(self, rule, endpoint=None, view_func=None, **options):
def add_url_rule(self, rule, endpoint=None, view_func=None, provide_automatic_options=None, **options):
"""Connects a URL rule. Works exactly like the :meth:`route`
decorator. If a view_func is provided it will be registered with the
endpoint.
@ -1017,6 +1080,10 @@ class Flask(_PackageBoundObject):
endpoint
:param view_func: the function to call when serving a request to the
provided endpoint
:param provide_automatic_options: controls whether the ``OPTIONS``
method should be added automatically. This can also be controlled
by setting the ``view_func.provide_automatic_options = False``
before adding the rule.
:param options: the options to be forwarded to the underlying
:class:`~werkzeug.routing.Rule` object. A change
to Werkzeug is handling of method options. methods
@ -1046,8 +1113,9 @@ class Flask(_PackageBoundObject):
# starting with Flask 0.8 the view_func object can disable and
# force-enable the automatic options handling.
provide_automatic_options = getattr(view_func,
'provide_automatic_options', None)
if provide_automatic_options is None:
provide_automatic_options = getattr(view_func,
'provide_automatic_options', None)
if provide_automatic_options is None:
if 'OPTIONS' not in methods:
@ -1133,7 +1201,9 @@ class Flask(_PackageBoundObject):
@setupmethod
def errorhandler(self, code_or_exception):
"""A decorator that is used to register a function give a given
"""Register a function to handle errors by code or exception class.
A decorator that is used to register a function given an
error code. Example::
@app.errorhandler(404)
@ -1146,21 +1216,6 @@ class Flask(_PackageBoundObject):
def special_exception_handler(error):
return 'Database connection failed', 500
You can also register a function as error handler without using
the :meth:`errorhandler` decorator. The following example is
equivalent to the one above::
def page_not_found(error):
return 'This page does not exist', 404
app.error_handler_spec[None][404] = page_not_found
Setting error handlers via assignments to :attr:`error_handler_spec`
however is discouraged as it requires fiddling with nested dictionaries
and the special case for arbitrary exception types.
The first ``None`` refers to the active blueprint. If the error
handler should be application wide ``None`` shall be used.
.. versionadded:: 0.7
Use :meth:`register_error_handler` instead of modifying
:attr:`error_handler_spec` directly, for application wide error
@ -1171,13 +1226,15 @@ class Flask(_PackageBoundObject):
that do not necessarily have to be a subclass of the
:class:`~werkzeug.exceptions.HTTPException` class.
:param code: the code as integer for the handler
:param code_or_exception: the code as integer for the handler, or
an arbitrary exception
"""
def decorator(f):
self._register_error_handler(None, code_or_exception, f)
return f
return decorator
@setupmethod
def register_error_handler(self, code_or_exception, f):
"""Alternative error attach function to the :meth:`errorhandler`
decorator that is more straightforward to use for non decorator
@ -1196,11 +1253,18 @@ class Flask(_PackageBoundObject):
"""
if isinstance(code_or_exception, HTTPException): # old broken behavior
raise ValueError(
'Tried to register a handler for an exception instance {0!r}. '
'Handlers can only be registered for exception classes or HTTP error codes.'
.format(code_or_exception))
'Tried to register a handler for an exception instance {0!r}.'
' Handlers can only be registered for exception classes or'
' HTTP error codes.'.format(code_or_exception)
)
exc_class, code = self._get_exc_class_and_code(code_or_exception)
try:
exc_class, code = self._get_exc_class_and_code(code_or_exception)
except KeyError:
raise KeyError(
"'{0}' is not a recognized HTTP error code. Use a subclass of"
" HTTPException with that code instead.".format(code_or_exception)
)
handlers = self.error_handler_spec.setdefault(key, {}).setdefault(code, {})
handlers[exc_class] = f
@ -1306,10 +1370,12 @@ class Flask(_PackageBoundObject):
def before_request(self, f):
"""Registers a function to run before each request.
The function will be called without any arguments.
If the function returns a non-None value, it's handled as
if it was the return value from the view and further
request handling is stopped.
For example, this can be used to open a database connection, or to load
the logged in user from the session.
The function will be called without any arguments. If it returns a
non-None value, the value is handled as if it was the return value from
the view, and further request handling is stopped.
"""
self.before_request_funcs.setdefault(None, []).append(f)
return f
@ -1365,7 +1431,7 @@ class Flask(_PackageBoundObject):
will have to surround the execution of these code by try/except
statements and log occurring errors.
When a teardown function was called because of a exception it will
When a teardown function was called because of an exception it will
be passed an error object.
The return values of teardown functions are ignored.
@ -1428,9 +1494,17 @@ class Flask(_PackageBoundObject):
@setupmethod
def url_value_preprocessor(self, f):
"""Registers a function as URL value preprocessor for all view
functions of the application. It's called before the view functions
are called and can modify the url values provided.
"""Register a URL value preprocessor function for all view
functions in the application. These functions will be called before the
:meth:`before_request` functions.
The function can modify the values captured from the matched url before
they are passed to the view. For example, this can be used to pop a
common language code value and place it in ``g`` rather than pass it to
every view.
The function is passed the endpoint name and values dict. The return
value is ignored.
"""
self.url_value_preprocessors.setdefault(None, []).append(f)
return f
@ -1445,43 +1519,28 @@ class Flask(_PackageBoundObject):
return f
def _find_error_handler(self, e):
"""Finds a registered error handler for the request’s blueprint.
Otherwise falls back to the app, returns None if not a suitable
handler is found.
"""Return a registered error handler for an exception in this order:
blueprint handler for a specific code, app handler for a specific code,
blueprint handler for an exception class, app handler for an exception
class, or ``None`` if a suitable handler is not found.
"""
exc_class, code = self._get_exc_class_and_code(type(e))
def find_handler(handler_map):
for name, c in (
(request.blueprint, code), (None, code),
(request.blueprint, None), (None, None)
):
handler_map = self.error_handler_spec.setdefault(name, {}).get(c)
if not handler_map:
return
queue = deque(exc_class.__mro__)
# Protect from geniuses who might create circular references in
# __mro__
done = set()
continue
while queue:
cls = queue.popleft()
if cls in done:
continue
done.add(cls)
for cls in exc_class.__mro__:
handler = handler_map.get(cls)
if handler is not None:
# cache for next time exc_class is raised
handler_map[exc_class] = handler
return handler
queue.extend(cls.__mro__)
# try blueprint handlers
handler = find_handler(self.error_handler_spec
.get(request.blueprint, {})
.get(code))
if handler is not None:
return handler
# fall back to app handlers
return find_handler(self.error_handler_spec[None].get(code))
def handle_http_exception(self, e):
"""Handles an HTTP exception. By default this will invoke the
registered error handlers and fall back to returning the
@ -1511,12 +1570,20 @@ class Flask(_PackageBoundObject):
traceback. This is helpful for debugging implicitly raised HTTP
exceptions.
.. versionchanged:: 1.0
Bad request errors are not trapped by default in debug mode.
.. versionadded:: 0.8
"""
if self.config['TRAP_HTTP_EXCEPTIONS']:
return True
if self.config['TRAP_BAD_REQUEST_ERRORS']:
trap_bad_request = self.config['TRAP_BAD_REQUEST_ERRORS']
# if unset, trap based on debug mode
if (trap_bad_request is None and self.debug) or trap_bad_request:
return isinstance(e, BadRequest)
return False
def handle_user_exception(self, e):
@ -1527,16 +1594,30 @@ class Flask(_PackageBoundObject):
function will either return a response value or reraise the
exception with the same traceback.
.. versionchanged:: 1.0
Key errors raised from request data like ``form`` show the the bad
key in debug mode rather than a generic bad request message.
.. versionadded:: 0.7
"""
exc_type, exc_value, tb = sys.exc_info()
assert exc_value is e
# ensure not to trash sys.exc_info() at that point in case someone
# wants the traceback preserved in handle_http_exception. Of course
# we cannot prevent users from trashing it themselves in a custom
# trap_http_exception method so that's their fault then.
# MultiDict passes the key to the exception, but that's ignored
# when generating the response message. Set an informative
# description for key errors in debug mode or when trapping errors.
if (
(self.debug or self.config['TRAP_BAD_REQUEST_ERRORS'])
and isinstance(e, BadRequestKeyError)
# only set it if it's still the default description
and e.description is BadRequestKeyError.description
):
e.description = "KeyError: '{0}'".format(*e.args)
if isinstance(e, HTTPException) and not self.trap_http_exception(e):
return self.handle_http_exception(e)
@ -1573,7 +1654,7 @@ class Flask(_PackageBoundObject):
self.log_exception((exc_type, exc_value, tb))
if handler is None:
return InternalServerError()
return handler(e)
return self.finalize_request(handler(e), from_error_handler=True)
def log_exception(self, exc_info):
"""Logs an exception. This is called by :meth:`handle_exception`
@ -1641,9 +1722,30 @@ class Flask(_PackageBoundObject):
rv = self.dispatch_request()
except Exception as e:
rv = self.handle_user_exception(e)
return self.finalize_request(rv)
def finalize_request(self, rv, from_error_handler=False):
"""Given the return value from a view function this finalizes
the request by converting it into a response and invoking the
postprocessing functions. This is invoked for both normal
request dispatching as well as error handlers.
Because this means that it might be called as a result of a
failure a special safe mode is available which can be enabled
with the `from_error_handler` flag. If enabled, failures in
response processing will be logged and otherwise ignored.
:internal:
"""
response = self.make_response(rv)
response = self.process_response(response)
request_finished.send(self, response=response)
try:
response = self.process_response(response)
request_finished.send(self, response=response)
except Exception:
if not from_error_handler:
raise
self.logger.exception('Request finalizing failed with an '
'error while handling an error')
return response
def try_trigger_before_first_request_functions(self):
@ -1696,62 +1798,106 @@ class Flask(_PackageBoundObject):
return False
def make_response(self, rv):
"""Converts the return value from a view function to a real
response object that is an instance of :attr:`response_class`.
"""Convert the return value from a view function to an instance of
:attr:`response_class`.
The following types are allowed for `rv`:
:param rv: the return value from the view function. The view function
must return a response. Returning ``None``, or the view ending
without returning, is not allowed. The following types are allowed
for ``view_rv``:
.. tabularcolumns:: |p{3.5cm}|p{9.5cm}|
``str`` (``unicode`` in Python 2)
A response object is created with the string encoded to UTF-8
as the body.
======================= ===========================================
:attr:`response_class` the object is returned unchanged
:class:`str` a response object is created with the
string as body
:class:`unicode` a response object is created with the
string encoded to utf-8 as body
a WSGI function the function is called as WSGI application
and buffered as response object
:class:`tuple` A tuple in the form ``(response, status,
headers)`` or ``(response, headers)``
where `response` is any of the
types defined here, `status` is a string
or an integer and `headers` is a list or
a dictionary with header values.
======================= ===========================================
``bytes`` (``str`` in Python 2)
A response object is created with the bytes as the body.
:param rv: the return value from the view function
``tuple``
Either ``(body, status, headers)``, ``(body, status)``, or
``(body, headers)``, where ``body`` is any of the other types
allowed here, ``status`` is a string or an integer, and
``headers`` is a dictionary or a list of ``(key, value)``
tuples. If ``body`` is a :attr:`response_class` instance,
``status`` overwrites the exiting value and ``headers`` are
extended.
:attr:`response_class`
The object is returned unchanged.
other :class:`~werkzeug.wrappers.Response` class
The object is coerced to :attr:`response_class`.
:func:`callable`
The function is called as a WSGI application. The result is
used to create a response object.
.. versionchanged:: 0.9
Previously a tuple was interpreted as the arguments for the
response object.
"""
status_or_headers = headers = None
if isinstance(rv, tuple):
rv, status_or_headers, headers = rv + (None,) * (3 - len(rv))
status = headers = None
# unpack tuple returns
if isinstance(rv, (tuple, list)):
len_rv = len(rv)
# a 3-tuple is unpacked directly
if len_rv == 3:
rv, status, headers = rv
# decide if a 2-tuple has status or headers
elif len_rv == 2:
if isinstance(rv[1], (Headers, dict, tuple, list)):
rv, headers = rv
else:
rv, status = rv
# other sized tuples are not allowed
else:
raise TypeError(
'The view function did not return a valid response tuple.'
' The tuple must have the form (body, status, headers),'
' (body, status), or (body, headers).'
)
# the body must not be None
if rv is None:
raise ValueError('View function did not return a response')
if isinstance(status_or_headers, (dict, list)):
headers, status_or_headers = status_or_headers, None
raise TypeError(
'The view function did not return a valid response. The'
' function either returned None or ended without a return'
' statement.'
)
# make sure the body is an instance of the response class
if not isinstance(rv, self.response_class):
# When we create a response object directly, we let the constructor
# set the headers and status. We do this because there can be
# some extra logic involved when creating these objects with
# specific values (like default content type selection).
if isinstance(rv, (text_type, bytes, bytearray)):
rv = self.response_class(rv, headers=headers,
status=status_or_headers)
headers = status_or_headers = None
# let the response class set the status and headers instead of
# waiting to do it manually, so that the class can handle any
# special logic
rv = self.response_class(rv, status=status, headers=headers)
status = headers = None
else:
rv = self.response_class.force_type(rv, request.environ)
# evaluate a WSGI callable, or coerce a different response
# class to the correct type
try:
rv = self.response_class.force_type(rv, request.environ)
except TypeError as e:
new_error = TypeError(
'{e}\nThe view function did not return a valid'
' response. The return type must be a string, tuple,'
' Response instance, or WSGI callable, but it was a'
' {rv.__class__.__name__}.'.format(e=e, rv=rv)
)
reraise(TypeError, new_error, sys.exc_info()[2])
if status_or_headers is not None:
if isinstance(status_or_headers, string_types):
rv.status = status_or_headers
# prefer the status if it was provided
if status is not None:
if isinstance(status, (text_type, bytes, bytearray)):
rv.status = status
else:
rv.status_code = status_or_headers
rv.status_code = status
# extend existing headers with provided headers
if headers:
rv.headers.extend(headers)
@ -1776,7 +1922,7 @@ class Flask(_PackageBoundObject):
if self.config['SERVER_NAME'] is not None:
return self.url_map.bind(
self.config['SERVER_NAME'],
script_name=self.config['APPLICATION_ROOT'] or '/',
script_name=self.config['APPLICATION_ROOT'],
url_scheme=self.config['PREFERRED_URL_SCHEME'])
def inject_url_defaults(self, endpoint, values):
@ -1814,16 +1960,16 @@ class Flask(_PackageBoundObject):
raise error
def preprocess_request(self):
"""Called before the actual request dispatching and will
call each :meth:`before_request` decorated function, passing no
arguments.
If any of these functions returns a value, it's handled as
if it was the return value from the view and further
request handling is stopped.
"""Called before the request is dispatched. Calls
:attr:`url_value_preprocessors` registered with the app and the
current blueprint (if any). Then calls :attr:`before_request_funcs`
registered with the app and the blueprint.
This also triggers the :meth:`url_value_processor` functions before
the actual :meth:`before_request` functions are called.
If any :meth:`before_request` handler returns a non-None value, the
value is handled as if it was the return value from the view, and
further request handling is stopped.
"""
bp = _request_ctx_stack.top.request.blueprint
funcs = self.url_value_preprocessors.get(None, ())
@ -1863,7 +2009,7 @@ class Flask(_PackageBoundObject):
for handler in funcs:
response = handler(response)
if not self.session_interface.is_null_session(ctx.session):
self.save_session(ctx.session, response)
self.session_interface.save_session(self, ctx.session, response)
return response
def do_teardown_request(self, exc=_sentinel):
@ -1948,10 +2094,19 @@ class Flask(_PackageBoundObject):
def test_request_context(self, *args, **kwargs):
"""Creates a WSGI environment from the given values (see
:class:`werkzeug.test.EnvironBuilder` for more information, this
function accepts the same arguments).
function accepts the same arguments plus two additional).
Additional arguments (only if ``base_url`` is not specified):
:param subdomain: subdomain to use for route matching
:param url_scheme: scheme for the request, default
``PREFERRED_URL_SCHEME`` or ``http``.
"""
from flask.testing import make_test_environ_builder
builder = make_test_environ_builder(self, *args, **kwargs)
try:
return self.request_context(builder.get_environ())
finally:
@ -1983,14 +2138,17 @@ class Flask(_PackageBoundObject):
exception context to start the response
"""
ctx = self.request_context(environ)
ctx.push()
error = None
try:
try:
ctx.push()
response = self.full_dispatch_request()
except Exception as e:
error = e
response = self.make_response(self.handle_exception(e))
response = self.handle_exception(e)
except:
error = sys.exc_info()[1]
raise
return response(environ, start_response)
finally:
if self.should_ignore_error(error):