FeatureEnVi: Visual Analytics for Feature Engineering Using Stepwise Selection and Semi-Automatic Extraction Approaches
https://doi.org/10.1109/TVCG.2022.3141040
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2334 lines
93 KiB
2334 lines
93 KiB
# -*- coding: utf-8 -*-
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"""
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flask.app
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~~~~~~~~~
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This module implements the central WSGI application object.
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:copyright: © 2010 by the Pallets team.
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:license: BSD, see LICENSE for more details.
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"""
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import os
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import sys
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import warnings
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from datetime import timedelta
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from functools import update_wrapper
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from itertools import chain
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from threading import Lock
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from werkzeug.datastructures import Headers, ImmutableDict
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from werkzeug.exceptions import BadRequest, BadRequestKeyError, HTTPException, \
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InternalServerError, MethodNotAllowed, default_exceptions
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from werkzeug.routing import BuildError, Map, RequestRedirect, \
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RoutingException, Rule
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from . import cli, json
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from ._compat import integer_types, reraise, string_types, text_type
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from .config import Config, ConfigAttribute
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from .ctx import AppContext, RequestContext, _AppCtxGlobals
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from .globals import _request_ctx_stack, g, request, session
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from .helpers import (
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_PackageBoundObject,
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_endpoint_from_view_func, find_package, get_env, get_debug_flag,
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get_flashed_messages, locked_cached_property, url_for, get_load_dotenv
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)
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from .logging import create_logger
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from .sessions import SecureCookieSessionInterface
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from .signals import appcontext_tearing_down, got_request_exception, \
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request_finished, request_started, request_tearing_down
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from .templating import DispatchingJinjaLoader, Environment, \
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_default_template_ctx_processor
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from .wrappers import Request, Response
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# a singleton sentinel value for parameter defaults
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_sentinel = object()
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def _make_timedelta(value):
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if not isinstance(value, timedelta):
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return timedelta(seconds=value)
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return value
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def setupmethod(f):
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"""Wraps a method so that it performs a check in debug mode if the
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first request was already handled.
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"""
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def wrapper_func(self, *args, **kwargs):
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if self.debug and self._got_first_request:
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raise AssertionError('A setup function was called after the '
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'first request was handled. This usually indicates a bug '
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'in the application where a module was not imported '
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'and decorators or other functionality was called too late.\n'
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'To fix this make sure to import all your view modules, '
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'database models and everything related at a central place '
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'before the application starts serving requests.')
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return f(self, *args, **kwargs)
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return update_wrapper(wrapper_func, f)
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class Flask(_PackageBoundObject):
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"""The flask object implements a WSGI application and acts as the central
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object. It is passed the name of the module or package of the
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application. Once it is created it will act as a central registry for
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the view functions, the URL rules, template configuration and much more.
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The name of the package is used to resolve resources from inside the
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package or the folder the module is contained in depending on if the
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package parameter resolves to an actual python package (a folder with
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an :file:`__init__.py` file inside) or a standard module (just a ``.py`` file).
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For more information about resource loading, see :func:`open_resource`.
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Usually you create a :class:`Flask` instance in your main module or
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in the :file:`__init__.py` file of your package like this::
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from flask import Flask
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app = Flask(__name__)
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.. admonition:: About the First Parameter
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The idea of the first parameter is to give Flask an idea of what
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belongs to your application. This name is used to find resources
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on the filesystem, can be used by extensions to improve debugging
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information and a lot more.
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So it's important what you provide there. If you are using a single
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module, `__name__` is always the correct value. If you however are
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using a package, it's usually recommended to hardcode the name of
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your package there.
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For example if your application is defined in :file:`yourapplication/app.py`
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you should create it with one of the two versions below::
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app = Flask('yourapplication')
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app = Flask(__name__.split('.')[0])
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Why is that? The application will work even with `__name__`, thanks
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to how resources are looked up. However it will make debugging more
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painful. Certain extensions can make assumptions based on the
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import name of your application. For example the Flask-SQLAlchemy
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extension will look for the code in your application that triggered
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an SQL query in debug mode. If the import name is not properly set
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up, that debugging information is lost. (For example it would only
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pick up SQL queries in `yourapplication.app` and not
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`yourapplication.views.frontend`)
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.. versionadded:: 0.7
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The `static_url_path`, `static_folder`, and `template_folder`
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parameters were added.
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.. versionadded:: 0.8
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The `instance_path` and `instance_relative_config` parameters were
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added.
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.. versionadded:: 0.11
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The `root_path` parameter was added.
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.. versionadded:: 1.0
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The ``host_matching`` and ``static_host`` parameters were added.
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.. versionadded:: 1.0
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The ``subdomain_matching`` parameter was added. Subdomain
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matching needs to be enabled manually now. Setting
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:data:`SERVER_NAME` does not implicitly enable it.
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:param import_name: the name of the application package
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:param static_url_path: can be used to specify a different path for the
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static files on the web. Defaults to the name
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of the `static_folder` folder.
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:param static_folder: the folder with static files that should be served
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at `static_url_path`. Defaults to the ``'static'``
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folder in the root path of the application.
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:param static_host: the host to use when adding the static route.
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Defaults to None. Required when using ``host_matching=True``
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with a ``static_folder`` configured.
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:param host_matching: set ``url_map.host_matching`` attribute.
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Defaults to False.
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:param subdomain_matching: consider the subdomain relative to
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:data:`SERVER_NAME` when matching routes. Defaults to False.
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:param template_folder: the folder that contains the templates that should
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be used by the application. Defaults to
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``'templates'`` folder in the root path of the
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application.
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:param instance_path: An alternative instance path for the application.
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By default the folder ``'instance'`` next to the
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package or module is assumed to be the instance
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path.
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:param instance_relative_config: if set to ``True`` relative filenames
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for loading the config are assumed to
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be relative to the instance path instead
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of the application root.
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:param root_path: Flask by default will automatically calculate the path
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to the root of the application. In certain situations
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this cannot be achieved (for instance if the package
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is a Python 3 namespace package) and needs to be
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manually defined.
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"""
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#: The class that is used for request objects. See :class:`~flask.Request`
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#: for more information.
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request_class = Request
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#: The class that is used for response objects. See
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#: :class:`~flask.Response` for more information.
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response_class = Response
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#: The class that is used for the Jinja environment.
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#:
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#: .. versionadded:: 0.11
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jinja_environment = Environment
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#: The class that is used for the :data:`~flask.g` instance.
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#:
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#: Example use cases for a custom class:
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#:
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#: 1. Store arbitrary attributes on flask.g.
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#: 2. Add a property for lazy per-request database connectors.
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#: 3. Return None instead of AttributeError on unexpected attributes.
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#: 4. Raise exception if an unexpected attr is set, a "controlled" flask.g.
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#:
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#: In Flask 0.9 this property was called `request_globals_class` but it
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#: was changed in 0.10 to :attr:`app_ctx_globals_class` because the
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#: flask.g object is now application context scoped.
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#:
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#: .. versionadded:: 0.10
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app_ctx_globals_class = _AppCtxGlobals
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#: The class that is used for the ``config`` attribute of this app.
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#: Defaults to :class:`~flask.Config`.
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#:
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#: Example use cases for a custom class:
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#:
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#: 1. Default values for certain config options.
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#: 2. Access to config values through attributes in addition to keys.
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#:
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#: .. versionadded:: 0.11
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config_class = Config
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#: The testing flag. Set this to ``True`` to enable the test mode of
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#: Flask extensions (and in the future probably also Flask itself).
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#: For example this might activate test helpers that have an
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#: additional runtime cost which should not be enabled by default.
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#:
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#: If this is enabled and PROPAGATE_EXCEPTIONS is not changed from the
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#: default it's implicitly enabled.
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#:
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#: This attribute can also be configured from the config with the
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#: ``TESTING`` configuration key. Defaults to ``False``.
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testing = ConfigAttribute('TESTING')
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#: If a secret key is set, cryptographic components can use this to
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#: sign cookies and other things. Set this to a complex random value
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#: when you want to use the secure cookie for instance.
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#:
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#: This attribute can also be configured from the config with the
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#: :data:`SECRET_KEY` configuration key. Defaults to ``None``.
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secret_key = ConfigAttribute('SECRET_KEY')
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#: The secure cookie uses this for the name of the session cookie.
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#:
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#: This attribute can also be configured from the config with the
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#: ``SESSION_COOKIE_NAME`` configuration key. Defaults to ``'session'``
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session_cookie_name = ConfigAttribute('SESSION_COOKIE_NAME')
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#: A :class:`~datetime.timedelta` which is used to set the expiration
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#: date of a permanent session. The default is 31 days which makes a
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#: permanent session survive for roughly one month.
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#:
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#: This attribute can also be configured from the config with the
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#: ``PERMANENT_SESSION_LIFETIME`` configuration key. Defaults to
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#: ``timedelta(days=31)``
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permanent_session_lifetime = ConfigAttribute('PERMANENT_SESSION_LIFETIME',
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get_converter=_make_timedelta)
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#: A :class:`~datetime.timedelta` which is used as default cache_timeout
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#: for the :func:`send_file` functions. The default is 12 hours.
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#:
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#: This attribute can also be configured from the config with the
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#: ``SEND_FILE_MAX_AGE_DEFAULT`` configuration key. This configuration
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#: variable can also be set with an integer value used as seconds.
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#: Defaults to ``timedelta(hours=12)``
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send_file_max_age_default = ConfigAttribute('SEND_FILE_MAX_AGE_DEFAULT',
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get_converter=_make_timedelta)
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#: Enable this if you want to use the X-Sendfile feature. Keep in
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#: mind that the server has to support this. This only affects files
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#: sent with the :func:`send_file` method.
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#:
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#: .. versionadded:: 0.2
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#:
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#: This attribute can also be configured from the config with the
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#: ``USE_X_SENDFILE`` configuration key. Defaults to ``False``.
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use_x_sendfile = ConfigAttribute('USE_X_SENDFILE')
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#: The JSON encoder class to use. Defaults to :class:`~flask.json.JSONEncoder`.
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#:
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#: .. versionadded:: 0.10
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json_encoder = json.JSONEncoder
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#: The JSON decoder class to use. Defaults to :class:`~flask.json.JSONDecoder`.
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#:
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#: .. versionadded:: 0.10
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json_decoder = json.JSONDecoder
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#: Options that are passed directly to the Jinja2 environment.
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jinja_options = ImmutableDict(
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extensions=['jinja2.ext.autoescape', 'jinja2.ext.with_']
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)
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#: Default configuration parameters.
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default_config = ImmutableDict({
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'ENV': None,
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'DEBUG': None,
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'TESTING': False,
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'PROPAGATE_EXCEPTIONS': None,
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'PRESERVE_CONTEXT_ON_EXCEPTION': None,
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'SECRET_KEY': None,
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'PERMANENT_SESSION_LIFETIME': timedelta(days=31),
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'USE_X_SENDFILE': False,
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'SERVER_NAME': None,
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'APPLICATION_ROOT': '/',
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'SESSION_COOKIE_NAME': 'session',
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'SESSION_COOKIE_DOMAIN': None,
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'SESSION_COOKIE_PATH': None,
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'SESSION_COOKIE_HTTPONLY': True,
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'SESSION_COOKIE_SECURE': False,
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'SESSION_COOKIE_SAMESITE': None,
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'SESSION_REFRESH_EACH_REQUEST': True,
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'MAX_CONTENT_LENGTH': None,
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'SEND_FILE_MAX_AGE_DEFAULT': timedelta(hours=12),
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'TRAP_BAD_REQUEST_ERRORS': None,
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'TRAP_HTTP_EXCEPTIONS': False,
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'EXPLAIN_TEMPLATE_LOADING': False,
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'PREFERRED_URL_SCHEME': 'http',
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'JSON_AS_ASCII': True,
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'JSON_SORT_KEYS': True,
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'JSONIFY_PRETTYPRINT_REGULAR': False,
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'JSONIFY_MIMETYPE': 'application/json',
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'TEMPLATES_AUTO_RELOAD': None,
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'MAX_COOKIE_SIZE': 4093,
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})
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#: The rule object to use for URL rules created. This is used by
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#: :meth:`add_url_rule`. Defaults to :class:`werkzeug.routing.Rule`.
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#:
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#: .. versionadded:: 0.7
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url_rule_class = Rule
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#: the test client that is used with when `test_client` is used.
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#:
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#: .. versionadded:: 0.7
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test_client_class = None
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#: The :class:`~click.testing.CliRunner` subclass, by default
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#: :class:`~flask.testing.FlaskCliRunner` that is used by
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#: :meth:`test_cli_runner`. Its ``__init__`` method should take a
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#: Flask app object as the first argument.
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#:
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#: .. versionadded:: 1.0
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test_cli_runner_class = None
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#: the session interface to use. By default an instance of
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#: :class:`~flask.sessions.SecureCookieSessionInterface` is used here.
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#:
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#: .. versionadded:: 0.8
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session_interface = SecureCookieSessionInterface()
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# TODO remove the next three attrs when Sphinx :inherited-members: works
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# https://github.com/sphinx-doc/sphinx/issues/741
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#: The name of the package or module that this app belongs to. Do not
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#: change this once it is set by the constructor.
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import_name = None
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#: Location of the template files to be added to the template lookup.
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#: ``None`` if templates should not be added.
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template_folder = None
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#: Absolute path to the package on the filesystem. Used to look up
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#: resources contained in the package.
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root_path = None
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def __init__(
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self,
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import_name,
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static_url_path=None,
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static_folder='static',
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static_host=None,
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host_matching=False,
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subdomain_matching=False,
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template_folder='templates',
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instance_path=None,
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instance_relative_config=False,
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root_path=None
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):
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_PackageBoundObject.__init__(
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self,
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import_name,
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template_folder=template_folder,
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root_path=root_path
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)
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if static_url_path is not None:
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self.static_url_path = static_url_path
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if static_folder is not None:
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self.static_folder = static_folder
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if instance_path is None:
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instance_path = self.auto_find_instance_path()
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elif not os.path.isabs(instance_path):
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raise ValueError(
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'If an instance path is provided it must be absolute.'
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' A relative path was given instead.'
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)
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#: Holds the path to the instance folder.
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#:
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#: .. versionadded:: 0.8
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self.instance_path = instance_path
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#: The configuration dictionary as :class:`Config`. This behaves
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#: exactly like a regular dictionary but supports additional methods
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#: to load a config from files.
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self.config = self.make_config(instance_relative_config)
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#: A dictionary of all view functions registered. The keys will
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#: be function names which are also used to generate URLs and
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#: the values are the function objects themselves.
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#: To register a view function, use the :meth:`route` decorator.
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self.view_functions = {}
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#: A dictionary of all registered error handlers. The key is ``None``
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#: for error handlers active on the application, otherwise the key is
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#: the name of the blueprint. Each key points to another dictionary
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#: where the key is the status code of the http exception. The
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#: special key ``None`` points to a list of tuples where the first item
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#: is the class for the instance check and the second the error handler
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#: function.
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#:
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#: To register an error handler, use the :meth:`errorhandler`
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#: decorator.
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self.error_handler_spec = {}
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#: A list of functions that are called when :meth:`url_for` raises a
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|
#: :exc:`~werkzeug.routing.BuildError`. Each function registered here
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|
#: is called with `error`, `endpoint` and `values`. If a function
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#: returns ``None`` or raises a :exc:`BuildError` the next function is
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#: tried.
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#:
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#: .. versionadded:: 0.9
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self.url_build_error_handlers = []
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#: A dictionary with lists of functions that will be called at the
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#: beginning of each request. The key of the dictionary is the name of
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#: the blueprint this function is active for, or ``None`` for all
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#: requests. To register a function, use the :meth:`before_request`
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#: decorator.
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self.before_request_funcs = {}
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#: A list of functions that will be called at the beginning of the
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#: first request to this instance. To register a function, use the
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#: :meth:`before_first_request` decorator.
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#:
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#: .. versionadded:: 0.8
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|
self.before_first_request_funcs = []
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#: A dictionary with lists of functions that should be called after
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#: each request. The key of the dictionary is the name of the blueprint
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#: this function is active for, ``None`` for all requests. This can for
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#: example be used to close database connections. To register a function
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#: here, use the :meth:`after_request` decorator.
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self.after_request_funcs = {}
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#: A dictionary with lists of functions that are called after
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#: each request, even if an exception has occurred. The key of the
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#: dictionary is the name of the blueprint this function is active for,
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#: ``None`` for all requests. These functions are not allowed to modify
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#: the request, and their return values are ignored. If an exception
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#: occurred while processing the request, it gets passed to each
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#: teardown_request function. To register a function here, use the
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#: :meth:`teardown_request` decorator.
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#:
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#: .. versionadded:: 0.7
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|
self.teardown_request_funcs = {}
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#: A list of functions that are called when the application context
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#: is destroyed. Since the application context is also torn down
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#: if the request ends this is the place to store code that disconnects
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#: from databases.
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#:
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#: .. versionadded:: 0.9
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self.teardown_appcontext_funcs = []
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#: A dictionary with lists of functions that are called before the
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#: :attr:`before_request_funcs` functions. The key of the dictionary is
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#: the name of the blueprint this function is active for, or ``None``
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#: for all requests. To register a function, use
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#: :meth:`url_value_preprocessor`.
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#:
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#: .. versionadded:: 0.7
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self.url_value_preprocessors = {}
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#: A dictionary with lists of functions that can be used as URL value
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#: preprocessors. The key ``None`` here is used for application wide
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#: callbacks, otherwise the key is the name of the blueprint.
|
|
#: Each of these functions has the chance to modify the dictionary
|
|
#: of URL values before they are used as the keyword arguments of the
|
|
#: view function. For each function registered this one should also
|
|
#: provide a :meth:`url_defaults` function that adds the parameters
|
|
#: automatically again that were removed that way.
|
|
#:
|
|
#: .. versionadded:: 0.7
|
|
self.url_default_functions = {}
|
|
|
|
#: A dictionary with list of functions that are called without argument
|
|
#: to populate the template context. The key of the dictionary is the
|
|
#: name of the blueprint this function is active for, ``None`` for all
|
|
#: requests. Each returns a dictionary that the template context is
|
|
#: updated with. To register a function here, use the
|
|
#: :meth:`context_processor` decorator.
|
|
self.template_context_processors = {
|
|
None: [_default_template_ctx_processor]
|
|
}
|
|
|
|
#: A list of shell context processor functions that should be run
|
|
#: when a shell context is created.
|
|
#:
|
|
#: .. versionadded:: 0.11
|
|
self.shell_context_processors = []
|
|
|
|
#: all the attached blueprints in a dictionary by name. Blueprints
|
|
#: can be attached multiple times so this dictionary does not tell
|
|
#: you how often they got attached.
|
|
#:
|
|
#: .. versionadded:: 0.7
|
|
self.blueprints = {}
|
|
self._blueprint_order = []
|
|
|
|
#: a place where extensions can store application specific state. For
|
|
#: example this is where an extension could store database engines and
|
|
#: similar things. For backwards compatibility extensions should register
|
|
#: themselves like this::
|
|
#:
|
|
#: if not hasattr(app, 'extensions'):
|
|
#: app.extensions = {}
|
|
#: app.extensions['extensionname'] = SomeObject()
|
|
#:
|
|
#: The key must match the name of the extension module. For example in
|
|
#: case of a "Flask-Foo" extension in `flask_foo`, the key would be
|
|
#: ``'foo'``.
|
|
#:
|
|
#: .. versionadded:: 0.7
|
|
self.extensions = {}
|
|
|
|
#: The :class:`~werkzeug.routing.Map` for this instance. You can use
|
|
#: this to change the routing converters after the class was created
|
|
#: but before any routes are connected. Example::
|
|
#:
|
|
#: from werkzeug.routing import BaseConverter
|
|
#:
|
|
#: class ListConverter(BaseConverter):
|
|
#: def to_python(self, value):
|
|
#: return value.split(',')
|
|
#: def to_url(self, values):
|
|
#: 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
|
|
self.subdomain_matching = subdomain_matching
|
|
|
|
# tracks internally if the application already handled at least one
|
|
# request.
|
|
self._got_first_request = False
|
|
self._before_request_lock = Lock()
|
|
|
|
# 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',
|
|
host=static_host,
|
|
view_func=self.send_static_file
|
|
)
|
|
|
|
#: The click command line context for this application. Commands
|
|
#: registered here show up in the :command:`flask` command once the
|
|
#: application has been discovered. The default commands are
|
|
#: provided by Flask itself and can be overridden.
|
|
#:
|
|
#: This is an instance of a :class:`click.Group` object.
|
|
self.cli = cli.AppGroup(self.name)
|
|
|
|
@locked_cached_property
|
|
def name(self):
|
|
"""The name of the application. This is usually the import name
|
|
with the difference that it's guessed from the run file if the
|
|
import name is main. This name is used as a display name when
|
|
Flask needs the name of the application. It can be set and overridden
|
|
to change the value.
|
|
|
|
.. versionadded:: 0.8
|
|
"""
|
|
if self.import_name == '__main__':
|
|
fn = getattr(sys.modules['__main__'], '__file__', None)
|
|
if fn is None:
|
|
return '__main__'
|
|
return os.path.splitext(os.path.basename(fn))[0]
|
|
return self.import_name
|
|
|
|
@property
|
|
def propagate_exceptions(self):
|
|
"""Returns the value of the ``PROPAGATE_EXCEPTIONS`` configuration
|
|
value in case it's set, otherwise a sensible default is returned.
|
|
|
|
.. versionadded:: 0.7
|
|
"""
|
|
rv = self.config['PROPAGATE_EXCEPTIONS']
|
|
if rv is not None:
|
|
return rv
|
|
return self.testing or self.debug
|
|
|
|
@property
|
|
def preserve_context_on_exception(self):
|
|
"""Returns the value of the ``PRESERVE_CONTEXT_ON_EXCEPTION``
|
|
configuration value in case it's set, otherwise a sensible default
|
|
is returned.
|
|
|
|
.. versionadded:: 0.7
|
|
"""
|
|
rv = self.config['PRESERVE_CONTEXT_ON_EXCEPTION']
|
|
if rv is not None:
|
|
return rv
|
|
return self.debug
|
|
|
|
@locked_cached_property
|
|
def logger(self):
|
|
"""The ``'flask.app'`` logger, a standard Python
|
|
:class:`~logging.Logger`.
|
|
|
|
In debug mode, the logger's :attr:`~logging.Logger.level` will be set
|
|
to :data:`~logging.DEBUG`.
|
|
|
|
If there are no handlers configured, a default handler will be added.
|
|
See :ref:`logging` for more information.
|
|
|
|
.. versionchanged:: 1.0
|
|
Behavior was simplified. The logger is always named
|
|
``flask.app``. The level is only set during configuration, it
|
|
doesn't check ``app.debug`` each time. Only one format is used,
|
|
not different ones depending on ``app.debug``. No handlers are
|
|
removed, and a handler is only added if no handlers are already
|
|
configured.
|
|
|
|
.. versionadded:: 0.3
|
|
"""
|
|
return create_logger(self)
|
|
|
|
@locked_cached_property
|
|
def jinja_env(self):
|
|
"""The Jinja2 environment used to load templates."""
|
|
return self.create_jinja_environment()
|
|
|
|
@property
|
|
def got_first_request(self):
|
|
"""This attribute is set to ``True`` if the application started
|
|
handling the first request.
|
|
|
|
.. versionadded:: 0.8
|
|
"""
|
|
return self._got_first_request
|
|
|
|
def make_config(self, instance_relative=False):
|
|
"""Used to create the config attribute by the Flask constructor.
|
|
The `instance_relative` parameter is passed in from the constructor
|
|
of Flask (there named `instance_relative_config`) and indicates if
|
|
the config should be relative to the instance path or the root path
|
|
of the application.
|
|
|
|
.. versionadded:: 0.8
|
|
"""
|
|
root_path = self.root_path
|
|
if instance_relative:
|
|
root_path = self.instance_path
|
|
defaults = dict(self.default_config)
|
|
defaults['ENV'] = get_env()
|
|
defaults['DEBUG'] = get_debug_flag()
|
|
return self.config_class(root_path, defaults)
|
|
|
|
def auto_find_instance_path(self):
|
|
"""Tries to locate the instance path if it was not provided to the
|
|
constructor of the application class. It will basically calculate
|
|
the path to a folder named ``instance`` next to your main file or
|
|
the package.
|
|
|
|
.. versionadded:: 0.8
|
|
"""
|
|
prefix, package_path = find_package(self.import_name)
|
|
if prefix is None:
|
|
return os.path.join(package_path, 'instance')
|
|
return os.path.join(prefix, 'var', self.name + '-instance')
|
|
|
|
def open_instance_resource(self, resource, mode='rb'):
|
|
"""Opens a resource from the application's instance folder
|
|
(:attr:`instance_path`). Otherwise works like
|
|
:meth:`open_resource`. Instance resources can also be opened for
|
|
writing.
|
|
|
|
:param resource: the name of the resource. To access resources within
|
|
subfolders use forward slashes as separator.
|
|
:param mode: resource file opening mode, default is 'rb'.
|
|
"""
|
|
return open(os.path.join(self.instance_path, resource), mode)
|
|
|
|
def _get_templates_auto_reload(self):
|
|
"""Reload templates when they are changed. Used by
|
|
:meth:`create_jinja_environment`.
|
|
|
|
This attribute can be configured with :data:`TEMPLATES_AUTO_RELOAD`. If
|
|
not set, it will be enabled in debug mode.
|
|
|
|
.. versionadded:: 1.0
|
|
This property was added but the underlying config and behavior
|
|
already existed.
|
|
"""
|
|
rv = self.config['TEMPLATES_AUTO_RELOAD']
|
|
return rv if rv is not None else self.debug
|
|
|
|
def _set_templates_auto_reload(self, value):
|
|
self.config['TEMPLATES_AUTO_RELOAD'] = value
|
|
|
|
templates_auto_reload = property(
|
|
_get_templates_auto_reload, _set_templates_auto_reload
|
|
)
|
|
del _get_templates_auto_reload, _set_templates_auto_reload
|
|
|
|
def create_jinja_environment(self):
|
|
"""Creates the Jinja2 environment based on :attr:`jinja_options`
|
|
and :meth:`select_jinja_autoescape`. Since 0.7 this also adds
|
|
the Jinja2 globals and filters after initialization. Override
|
|
this function to customize the behavior.
|
|
|
|
.. versionadded:: 0.5
|
|
.. versionchanged:: 0.11
|
|
``Environment.auto_reload`` set in accordance with
|
|
``TEMPLATES_AUTO_RELOAD`` configuration option.
|
|
"""
|
|
options = dict(self.jinja_options)
|
|
|
|
if 'autoescape' not in options:
|
|
options['autoescape'] = self.select_jinja_autoescape
|
|
|
|
if 'auto_reload' not in options:
|
|
options['auto_reload'] = self.templates_auto_reload
|
|
|
|
rv = self.jinja_environment(self, **options)
|
|
rv.globals.update(
|
|
url_for=url_for,
|
|
get_flashed_messages=get_flashed_messages,
|
|
config=self.config,
|
|
# request, session and g are normally added with the
|
|
# context processor for efficiency reasons but for imported
|
|
# templates we also want the proxies in there.
|
|
request=request,
|
|
session=session,
|
|
g=g
|
|
)
|
|
rv.filters['tojson'] = json.tojson_filter
|
|
return rv
|
|
|
|
def create_global_jinja_loader(self):
|
|
"""Creates the loader for the Jinja2 environment. Can be used to
|
|
override just the loader and keeping the rest unchanged. It's
|
|
discouraged to override this function. Instead one should override
|
|
the :meth:`jinja_loader` function instead.
|
|
|
|
The global loader dispatches between the loaders of the application
|
|
and the individual blueprints.
|
|
|
|
.. versionadded:: 0.7
|
|
"""
|
|
return DispatchingJinjaLoader(self)
|
|
|
|
def select_jinja_autoescape(self, filename):
|
|
"""Returns ``True`` if autoescaping should be active for the given
|
|
template name. If no template name is given, returns `True`.
|
|
|
|
.. versionadded:: 0.5
|
|
"""
|
|
if filename is None:
|
|
return True
|
|
return filename.endswith(('.html', '.htm', '.xml', '.xhtml'))
|
|
|
|
def update_template_context(self, context):
|
|
"""Update the template context with some commonly used variables.
|
|
This injects request, session, config and g into the template
|
|
context as well as everything template context processors want
|
|
to inject. Note that the as of Flask 0.6, the original values
|
|
in the context will not be overridden if a context processor
|
|
decides to return a value with the same key.
|
|
|
|
:param context: the context as a dictionary that is updated in place
|
|
to add extra variables.
|
|
"""
|
|
funcs = self.template_context_processors[None]
|
|
reqctx = _request_ctx_stack.top
|
|
if reqctx is not None:
|
|
bp = reqctx.request.blueprint
|
|
if bp is not None and bp in self.template_context_processors:
|
|
funcs = chain(funcs, self.template_context_processors[bp])
|
|
orig_ctx = context.copy()
|
|
for func in funcs:
|
|
context.update(func())
|
|
# make sure the original values win. This makes it possible to
|
|
# easier add new variables in context processors without breaking
|
|
# existing views.
|
|
context.update(orig_ctx)
|
|
|
|
def make_shell_context(self):
|
|
"""Returns the shell context for an interactive shell for this
|
|
application. This runs all the registered shell context
|
|
processors.
|
|
|
|
.. versionadded:: 0.11
|
|
"""
|
|
rv = {'app': self, 'g': g}
|
|
for processor in self.shell_context_processors:
|
|
rv.update(processor())
|
|
return rv
|
|
|
|
#: What environment the app is running in. Flask and extensions may
|
|
#: enable behaviors based on the environment, such as enabling debug
|
|
#: mode. This maps to the :data:`ENV` config key. This is set by the
|
|
#: :envvar:`FLASK_ENV` environment variable and may not behave as
|
|
#: expected if set in code.
|
|
#:
|
|
#: **Do not enable development when deploying in production.**
|
|
#:
|
|
#: Default: ``'production'``
|
|
env = ConfigAttribute('ENV')
|
|
|
|
def _get_debug(self):
|
|
return self.config['DEBUG']
|
|
|
|
def _set_debug(self, value):
|
|
self.config['DEBUG'] = value
|
|
self.jinja_env.auto_reload = self.templates_auto_reload
|
|
|
|
#: Whether debug mode is enabled. When using ``flask run`` to start
|
|
#: the development server, an interactive debugger will be shown for
|
|
#: unhandled exceptions, and the server will be reloaded when code
|
|
#: changes. This maps to the :data:`DEBUG` config key. This is
|
|
#: enabled when :attr:`env` is ``'development'`` and is overridden
|
|
#: by the ``FLASK_DEBUG`` environment variable. It may not behave as
|
|
#: expected if set in code.
|
|
#:
|
|
#: **Do not enable debug mode when deploying in production.**
|
|
#:
|
|
#: Default: ``True`` if :attr:`env` is ``'development'``, or
|
|
#: ``False`` otherwise.
|
|
debug = property(_get_debug, _set_debug)
|
|
del _get_debug, _set_debug
|
|
|
|
def run(self, host=None, port=None, debug=None,
|
|
load_dotenv=True, **options):
|
|
"""Runs the application on a local development server.
|
|
|
|
Do not use ``run()`` in a production setting. It is not intended to
|
|
meet security and performance requirements for a production server.
|
|
Instead, see :ref:`deployment` for WSGI server recommendations.
|
|
|
|
If the :attr:`debug` flag is set the server will automatically reload
|
|
for code changes and show a debugger in case an exception happened.
|
|
|
|
If you want to run the application in debug mode, but disable the
|
|
code execution on the interactive debugger, you can pass
|
|
``use_evalex=False`` as parameter. This will keep the debugger's
|
|
traceback screen active, but disable code execution.
|
|
|
|
It is not recommended to use this function for development with
|
|
automatic reloading as this is badly supported. Instead you should
|
|
be using the :command:`flask` command line script's ``run`` support.
|
|
|
|
.. admonition:: Keep in Mind
|
|
|
|
Flask will suppress any server error with a generic error page
|
|
unless it is in debug mode. As such to enable just the
|
|
interactive debugger without the code reloading, you have to
|
|
invoke :meth:`run` with ``debug=True`` and ``use_reloader=False``.
|
|
Setting ``use_debugger`` to ``True`` without being in debug mode
|
|
won't catch any exceptions because there won't be any to
|
|
catch.
|
|
|
|
: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'`` 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.
|
|
:param debug: if given, enable or disable debug mode. See
|
|
:attr:`debug`.
|
|
:param load_dotenv: Load the nearest :file:`.env` and :file:`.flaskenv`
|
|
files to set environment variables. Will also change the working
|
|
directory to the directory containing the first file found.
|
|
:param options: the options to be forwarded to the underlying Werkzeug
|
|
server. See :func:`werkzeug.serving.run_simple` for more
|
|
information.
|
|
|
|
.. versionchanged:: 1.0
|
|
If installed, python-dotenv will be used to load environment
|
|
variables from :file:`.env` and :file:`.flaskenv` files.
|
|
|
|
If set, the :envvar:`FLASK_ENV` and :envvar:`FLASK_DEBUG`
|
|
environment variables will override :attr:`env` and
|
|
:attr:`debug`.
|
|
|
|
Threaded mode is enabled by default.
|
|
|
|
.. versionchanged:: 0.10
|
|
The default port is now picked from the ``SERVER_NAME``
|
|
variable.
|
|
"""
|
|
# 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') == 'true':
|
|
from .debughelpers import explain_ignored_app_run
|
|
explain_ignored_app_run()
|
|
return
|
|
|
|
if get_load_dotenv(load_dotenv):
|
|
cli.load_dotenv()
|
|
|
|
# if set, let env vars override previous values
|
|
if 'FLASK_ENV' in os.environ:
|
|
self.env = get_env()
|
|
self.debug = get_debug_flag()
|
|
elif 'FLASK_DEBUG' in os.environ:
|
|
self.debug = get_debug_flag()
|
|
|
|
# debug passed to method overrides all other sources
|
|
if debug is not None:
|
|
self.debug = bool(debug)
|
|
|
|
_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)
|
|
|
|
options.setdefault('use_reloader', self.debug)
|
|
options.setdefault('use_debugger', self.debug)
|
|
options.setdefault('threaded', True)
|
|
|
|
cli.show_server_banner(self.env, self.debug, self.name, False)
|
|
|
|
from werkzeug.serving import run_simple
|
|
|
|
try:
|
|
run_simple(host, port, self, **options)
|
|
finally:
|
|
# reset the first request information if the development 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
|
|
|
|
def test_client(self, use_cookies=True, **kwargs):
|
|
"""Creates a test client for this application. For information
|
|
about unit testing head over to :ref:`testing`.
|
|
|
|
Note that if you are testing for assertions or exceptions in your
|
|
application code, you must set ``app.testing = True`` in order for the
|
|
exceptions to propagate to the test client. Otherwise, the exception
|
|
will be handled by the application (not visible to the test client) and
|
|
the only indication of an AssertionError or other exception will be a
|
|
500 status code response to the test client. See the :attr:`testing`
|
|
attribute. For example::
|
|
|
|
app.testing = True
|
|
client = app.test_client()
|
|
|
|
The test client can be used in a ``with`` block to defer the closing down
|
|
of the context until the end of the ``with`` block. This is useful if
|
|
you want to access the context locals for testing::
|
|
|
|
with app.test_client() as c:
|
|
rv = c.get('/?vodka=42')
|
|
assert request.args['vodka'] == '42'
|
|
|
|
Additionally, you may pass optional keyword arguments that will then
|
|
be passed to the application's :attr:`test_client_class` constructor.
|
|
For example::
|
|
|
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from flask.testing import FlaskClient
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|
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class CustomClient(FlaskClient):
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def __init__(self, *args, **kwargs):
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self._authentication = kwargs.pop("authentication")
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super(CustomClient,self).__init__( *args, **kwargs)
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app.test_client_class = CustomClient
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client = app.test_client(authentication='Basic ....')
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See :class:`~flask.testing.FlaskClient` for more information.
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|
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.. versionchanged:: 0.4
|
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added support for ``with`` block usage for the client.
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|
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.. versionadded:: 0.7
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The `use_cookies` parameter was added as well as the ability
|
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to override the client to be used by setting the
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:attr:`test_client_class` attribute.
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|
|
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.. versionchanged:: 0.11
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Added `**kwargs` to support passing additional keyword arguments to
|
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the constructor of :attr:`test_client_class`.
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"""
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cls = self.test_client_class
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if cls is None:
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from flask.testing import FlaskClient as cls
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return cls(self, self.response_class, use_cookies=use_cookies, **kwargs)
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def test_cli_runner(self, **kwargs):
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"""Create a CLI runner for testing CLI commands.
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See :ref:`testing-cli`.
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Returns an instance of :attr:`test_cli_runner_class`, by default
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:class:`~flask.testing.FlaskCliRunner`. The Flask app object is
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passed as the first argument.
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.. versionadded:: 1.0
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"""
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cls = self.test_cli_runner_class
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if cls is None:
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from flask.testing import FlaskCliRunner as cls
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return cls(self, **kwargs)
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def open_session(self, request):
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"""Creates or opens a new session. Default implementation stores all
|
|
session data in a signed cookie. This requires that the
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:attr:`secret_key` is set. Instead of overriding this method
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we recommend replacing the :class:`session_interface`.
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.. deprecated: 1.0
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Will be removed in 1.1. Use ``session_interface.open_session``
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instead.
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:param request: an instance of :attr:`request_class`.
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"""
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warnings.warn(DeprecationWarning(
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'"open_session" is deprecated and will be removed in 1.1. Use'
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' "session_interface.open_session" instead.'
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))
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return self.session_interface.open_session(self, request)
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def save_session(self, session, response):
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"""Saves the session if it needs updates. For the default
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|
implementation, check :meth:`open_session`. Instead of overriding this
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method we recommend replacing the :class:`session_interface`.
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.. deprecated: 1.0
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|
Will be removed in 1.1. Use ``session_interface.save_session``
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|
instead.
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|
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:param session: the session to be saved (a
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:class:`~werkzeug.contrib.securecookie.SecureCookie`
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object)
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:param response: an instance of :attr:`response_class`
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"""
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warnings.warn(DeprecationWarning(
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'"save_session" is deprecated and will be removed in 1.1. Use'
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' "session_interface.save_session" instead.'
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))
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return self.session_interface.save_session(self, session, response)
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|
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def make_null_session(self):
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"""Creates a new instance of a missing session. Instead of overriding
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this method we recommend replacing the :class:`session_interface`.
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.. deprecated: 1.0
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|
Will be removed in 1.1. Use ``session_interface.make_null_session``
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instead.
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.. versionadded:: 0.7
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"""
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|
|
|
warnings.warn(DeprecationWarning(
|
|
'"make_null_session" is deprecated and will be removed in 1.1. Use'
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' "session_interface.make_null_session" instead.'
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))
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return self.session_interface.make_null_session(self)
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|
|
@setupmethod
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def register_blueprint(self, blueprint, **options):
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"""Register a :class:`~flask.Blueprint` on the application. Keyword
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|
arguments passed to this method will override the defaults set on the
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blueprint.
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Calls the blueprint's :meth:`~flask.Blueprint.register` method after
|
|
recording the blueprint in the application's :attr:`blueprints`.
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:param blueprint: The blueprint to register.
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|
: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.
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|
:param options: Additional keyword arguments are passed to
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|
:class:`~flask.blueprints.BlueprintSetupState`. They can be
|
|
accessed in :meth:`~flask.Blueprint.record` callbacks.
|
|
|
|
.. versionadded:: 0.7
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"""
|
|
first_registration = False
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|
|
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if blueprint.name in self.blueprints:
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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.' % (
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blueprint, self.blueprints[blueprint.name], blueprint.name
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|
)
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)
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|
else:
|
|
self.blueprints[blueprint.name] = blueprint
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|
self._blueprint_order.append(blueprint)
|
|
first_registration = True
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|
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blueprint.register(self, options, first_registration)
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|
|
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def iter_blueprints(self):
|
|
"""Iterates over all blueprints by the order they were registered.
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|
|
|
.. versionadded:: 0.11
|
|
"""
|
|
return iter(self._blueprint_order)
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|
|
|
@setupmethod
|
|
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.
|
|
|
|
Basically this example::
|
|
|
|
@app.route('/')
|
|
def index():
|
|
pass
|
|
|
|
Is equivalent to the following::
|
|
|
|
def index():
|
|
pass
|
|
app.add_url_rule('/', 'index', index)
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|
|
|
If the view_func is not provided you will need to connect the endpoint
|
|
to a view function like so::
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|
|
|
app.view_functions['index'] = index
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|
|
|
Internally :meth:`route` invokes :meth:`add_url_rule` so if you want
|
|
to customize the behavior via subclassing you only need to change
|
|
this method.
|
|
|
|
For more information refer to :ref:`url-route-registrations`.
|
|
|
|
.. versionchanged:: 0.2
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|
`view_func` parameter added.
|
|
|
|
.. versionchanged:: 0.6
|
|
``OPTIONS`` is added automatically as method.
|
|
|
|
:param rule: the URL rule as string
|
|
:param endpoint: the endpoint for the registered URL rule. Flask
|
|
itself assumes the name of the view function as
|
|
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
|
|
is a list of methods this rule should be limited
|
|
to (``GET``, ``POST`` etc.). By default a rule
|
|
just listens for ``GET`` (and implicitly ``HEAD``).
|
|
Starting with Flask 0.6, ``OPTIONS`` is implicitly
|
|
added and handled by the standard request handling.
|
|
"""
|
|
if endpoint is None:
|
|
endpoint = _endpoint_from_view_func(view_func)
|
|
options['endpoint'] = endpoint
|
|
methods = options.pop('methods', None)
|
|
|
|
# if the methods are not given and the view_func object knows its
|
|
# methods we can use that instead. If neither exists, we go with
|
|
# a tuple of only ``GET`` as default.
|
|
if methods is None:
|
|
methods = getattr(view_func, 'methods', None) or ('GET',)
|
|
if isinstance(methods, string_types):
|
|
raise TypeError('Allowed methods have to be iterables of strings, '
|
|
'for example: @app.route(..., methods=["POST"])')
|
|
methods = set(item.upper() for item in methods)
|
|
|
|
# Methods that should always be added
|
|
required_methods = set(getattr(view_func, 'required_methods', ()))
|
|
|
|
# starting with Flask 0.8 the view_func object can disable and
|
|
# force-enable the automatic options handling.
|
|
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:
|
|
provide_automatic_options = True
|
|
required_methods.add('OPTIONS')
|
|
else:
|
|
provide_automatic_options = False
|
|
|
|
# Add the required methods now.
|
|
methods |= required_methods
|
|
|
|
rule = self.url_rule_class(rule, methods=methods, **options)
|
|
rule.provide_automatic_options = provide_automatic_options
|
|
|
|
self.url_map.add(rule)
|
|
if view_func is not None:
|
|
old_func = self.view_functions.get(endpoint)
|
|
if old_func is not None and old_func != view_func:
|
|
raise AssertionError('View function mapping is overwriting an '
|
|
'existing endpoint function: %s' % endpoint)
|
|
self.view_functions[endpoint] = view_func
|
|
|
|
def route(self, rule, **options):
|
|
"""A decorator that is used to register a view function for a
|
|
given URL rule. This does the same thing as :meth:`add_url_rule`
|
|
but is intended for decorator usage::
|
|
|
|
@app.route('/')
|
|
def index():
|
|
return 'Hello World'
|
|
|
|
For more information refer to :ref:`url-route-registrations`.
|
|
|
|
:param rule: the URL rule as string
|
|
:param endpoint: the endpoint for the registered URL rule. Flask
|
|
itself assumes the name of the view function as
|
|
endpoint
|
|
: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
|
|
is a list of methods this rule should be limited
|
|
to (``GET``, ``POST`` etc.). By default a rule
|
|
just listens for ``GET`` (and implicitly ``HEAD``).
|
|
Starting with Flask 0.6, ``OPTIONS`` is implicitly
|
|
added and handled by the standard request handling.
|
|
"""
|
|
def decorator(f):
|
|
endpoint = options.pop('endpoint', None)
|
|
self.add_url_rule(rule, endpoint, f, **options)
|
|
return f
|
|
return decorator
|
|
|
|
@setupmethod
|
|
def endpoint(self, endpoint):
|
|
"""A decorator to register a function as an endpoint.
|
|
Example::
|
|
|
|
@app.endpoint('example.endpoint')
|
|
def example():
|
|
return "example"
|
|
|
|
:param endpoint: the name of the endpoint
|
|
"""
|
|
def decorator(f):
|
|
self.view_functions[endpoint] = f
|
|
return f
|
|
return decorator
|
|
|
|
@staticmethod
|
|
def _get_exc_class_and_code(exc_class_or_code):
|
|
"""Ensure that we register only exceptions as handler keys"""
|
|
if isinstance(exc_class_or_code, integer_types):
|
|
exc_class = default_exceptions[exc_class_or_code]
|
|
else:
|
|
exc_class = exc_class_or_code
|
|
|
|
assert issubclass(exc_class, Exception)
|
|
|
|
if issubclass(exc_class, HTTPException):
|
|
return exc_class, exc_class.code
|
|
else:
|
|
return exc_class, None
|
|
|
|
@setupmethod
|
|
def errorhandler(self, code_or_exception):
|
|
"""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)
|
|
def page_not_found(error):
|
|
return 'This page does not exist', 404
|
|
|
|
You can also register handlers for arbitrary exceptions::
|
|
|
|
@app.errorhandler(DatabaseError)
|
|
def special_exception_handler(error):
|
|
return 'Database connection failed', 500
|
|
|
|
.. versionadded:: 0.7
|
|
Use :meth:`register_error_handler` instead of modifying
|
|
:attr:`error_handler_spec` directly, for application wide error
|
|
handlers.
|
|
|
|
.. versionadded:: 0.7
|
|
One can now additionally also register custom exception types
|
|
that do not necessarily have to be a subclass of the
|
|
:class:`~werkzeug.exceptions.HTTPException` class.
|
|
|
|
: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
|
|
usage.
|
|
|
|
.. versionadded:: 0.7
|
|
"""
|
|
self._register_error_handler(None, code_or_exception, f)
|
|
|
|
@setupmethod
|
|
def _register_error_handler(self, key, code_or_exception, f):
|
|
"""
|
|
:type key: None|str
|
|
:type code_or_exception: int|T<=Exception
|
|
:type f: callable
|
|
"""
|
|
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)
|
|
)
|
|
|
|
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
|
|
|
|
@setupmethod
|
|
def template_filter(self, name=None):
|
|
"""A decorator that is used to register custom template filter.
|
|
You can specify a name for the filter, otherwise the function
|
|
name will be used. Example::
|
|
|
|
@app.template_filter()
|
|
def reverse(s):
|
|
return s[::-1]
|
|
|
|
:param name: the optional name of the filter, otherwise the
|
|
function name will be used.
|
|
"""
|
|
def decorator(f):
|
|
self.add_template_filter(f, name=name)
|
|
return f
|
|
return decorator
|
|
|
|
@setupmethod
|
|
def add_template_filter(self, f, name=None):
|
|
"""Register a custom template filter. Works exactly like the
|
|
:meth:`template_filter` decorator.
|
|
|
|
:param name: the optional name of the filter, otherwise the
|
|
function name will be used.
|
|
"""
|
|
self.jinja_env.filters[name or f.__name__] = f
|
|
|
|
@setupmethod
|
|
def template_test(self, name=None):
|
|
"""A decorator that is used to register custom template test.
|
|
You can specify a name for the test, otherwise the function
|
|
name will be used. Example::
|
|
|
|
@app.template_test()
|
|
def is_prime(n):
|
|
if n == 2:
|
|
return True
|
|
for i in range(2, int(math.ceil(math.sqrt(n))) + 1):
|
|
if n % i == 0:
|
|
return False
|
|
return True
|
|
|
|
.. versionadded:: 0.10
|
|
|
|
:param name: the optional name of the test, otherwise the
|
|
function name will be used.
|
|
"""
|
|
def decorator(f):
|
|
self.add_template_test(f, name=name)
|
|
return f
|
|
return decorator
|
|
|
|
@setupmethod
|
|
def add_template_test(self, f, name=None):
|
|
"""Register a custom template test. Works exactly like the
|
|
:meth:`template_test` decorator.
|
|
|
|
.. versionadded:: 0.10
|
|
|
|
:param name: the optional name of the test, otherwise the
|
|
function name will be used.
|
|
"""
|
|
self.jinja_env.tests[name or f.__name__] = f
|
|
|
|
@setupmethod
|
|
def template_global(self, name=None):
|
|
"""A decorator that is used to register a custom template global function.
|
|
You can specify a name for the global function, otherwise the function
|
|
name will be used. Example::
|
|
|
|
@app.template_global()
|
|
def double(n):
|
|
return 2 * n
|
|
|
|
.. versionadded:: 0.10
|
|
|
|
:param name: the optional name of the global function, otherwise the
|
|
function name will be used.
|
|
"""
|
|
def decorator(f):
|
|
self.add_template_global(f, name=name)
|
|
return f
|
|
return decorator
|
|
|
|
@setupmethod
|
|
def add_template_global(self, f, name=None):
|
|
"""Register a custom template global function. Works exactly like the
|
|
:meth:`template_global` decorator.
|
|
|
|
.. versionadded:: 0.10
|
|
|
|
:param name: the optional name of the global function, otherwise the
|
|
function name will be used.
|
|
"""
|
|
self.jinja_env.globals[name or f.__name__] = f
|
|
|
|
@setupmethod
|
|
def before_request(self, f):
|
|
"""Registers a function to run before each request.
|
|
|
|
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
|
|
|
|
@setupmethod
|
|
def before_first_request(self, f):
|
|
"""Registers a function to be run before the first request to this
|
|
instance of the application.
|
|
|
|
The function will be called without any arguments and its return
|
|
value is ignored.
|
|
|
|
.. versionadded:: 0.8
|
|
"""
|
|
self.before_first_request_funcs.append(f)
|
|
return f
|
|
|
|
@setupmethod
|
|
def after_request(self, f):
|
|
"""Register a function to be run after each request.
|
|
|
|
Your function must take one parameter, an instance of
|
|
:attr:`response_class` and return a new response object or the
|
|
same (see :meth:`process_response`).
|
|
|
|
As of Flask 0.7 this function might not be executed at the end of the
|
|
request in case an unhandled exception occurred.
|
|
"""
|
|
self.after_request_funcs.setdefault(None, []).append(f)
|
|
return f
|
|
|
|
@setupmethod
|
|
def teardown_request(self, f):
|
|
"""Register a function to be run at the end of each request,
|
|
regardless of whether there was an exception or not. These functions
|
|
are executed when the request context is popped, even if not an
|
|
actual request was performed.
|
|
|
|
Example::
|
|
|
|
ctx = app.test_request_context()
|
|
ctx.push()
|
|
...
|
|
ctx.pop()
|
|
|
|
When ``ctx.pop()`` is executed in the above example, the teardown
|
|
functions are called just before the request context moves from the
|
|
stack of active contexts. This becomes relevant if you are using
|
|
such constructs in tests.
|
|
|
|
Generally teardown functions must take every necessary step to avoid
|
|
that they will fail. If they do execute code that might fail they
|
|
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 an exception it will
|
|
be passed an error object.
|
|
|
|
The return values of teardown functions are ignored.
|
|
|
|
.. admonition:: Debug Note
|
|
|
|
In debug mode Flask will not tear down a request on an exception
|
|
immediately. Instead it will keep it alive so that the interactive
|
|
debugger can still access it. This behavior can be controlled
|
|
by the ``PRESERVE_CONTEXT_ON_EXCEPTION`` configuration variable.
|
|
"""
|
|
self.teardown_request_funcs.setdefault(None, []).append(f)
|
|
return f
|
|
|
|
@setupmethod
|
|
def teardown_appcontext(self, f):
|
|
"""Registers a function to be called when the application context
|
|
ends. These functions are typically also called when the request
|
|
context is popped.
|
|
|
|
Example::
|
|
|
|
ctx = app.app_context()
|
|
ctx.push()
|
|
...
|
|
ctx.pop()
|
|
|
|
When ``ctx.pop()`` is executed in the above example, the teardown
|
|
functions are called just before the app context moves from the
|
|
stack of active contexts. This becomes relevant if you are using
|
|
such constructs in tests.
|
|
|
|
Since a request context typically also manages an application
|
|
context it would also be called when you pop a request context.
|
|
|
|
When a teardown function was called because of an unhandled exception
|
|
it will be passed an error object. If an :meth:`errorhandler` is
|
|
registered, it will handle the exception and the teardown will not
|
|
receive it.
|
|
|
|
The return values of teardown functions are ignored.
|
|
|
|
.. versionadded:: 0.9
|
|
"""
|
|
self.teardown_appcontext_funcs.append(f)
|
|
return f
|
|
|
|
@setupmethod
|
|
def context_processor(self, f):
|
|
"""Registers a template context processor function."""
|
|
self.template_context_processors[None].append(f)
|
|
return f
|
|
|
|
@setupmethod
|
|
def shell_context_processor(self, f):
|
|
"""Registers a shell context processor function.
|
|
|
|
.. versionadded:: 0.11
|
|
"""
|
|
self.shell_context_processors.append(f)
|
|
return f
|
|
|
|
@setupmethod
|
|
def url_value_preprocessor(self, f):
|
|
"""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
|
|
|
|
@setupmethod
|
|
def url_defaults(self, f):
|
|
"""Callback function for URL defaults for all view functions of the
|
|
application. It's called with the endpoint and values and should
|
|
update the values passed in place.
|
|
"""
|
|
self.url_default_functions.setdefault(None, []).append(f)
|
|
return f
|
|
|
|
def _find_error_handler(self, e):
|
|
"""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))
|
|
|
|
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:
|
|
continue
|
|
|
|
for cls in exc_class.__mro__:
|
|
handler = handler_map.get(cls)
|
|
|
|
if handler is not None:
|
|
return handler
|
|
|
|
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
|
|
exception as response.
|
|
|
|
.. versionchanged:: 1.0.3
|
|
``RoutingException``, used internally for actions such as
|
|
slash redirects during routing, is not passed to error
|
|
handlers.
|
|
|
|
.. versionchanged:: 1.0
|
|
Exceptions are looked up by code *and* by MRO, so
|
|
``HTTPExcpetion`` subclasses can be handled with a catch-all
|
|
handler for the base ``HTTPException``.
|
|
|
|
.. versionadded:: 0.3
|
|
"""
|
|
# Proxy exceptions don't have error codes. We want to always return
|
|
# those unchanged as errors
|
|
if e.code is None:
|
|
return e
|
|
|
|
# RoutingExceptions are used internally to trigger routing
|
|
# actions, such as slash redirects raising RequestRedirect. They
|
|
# are not raised or handled in user code.
|
|
if isinstance(e, RoutingException):
|
|
return e
|
|
|
|
handler = self._find_error_handler(e)
|
|
if handler is None:
|
|
return e
|
|
return handler(e)
|
|
|
|
def trap_http_exception(self, e):
|
|
"""Checks if an HTTP exception should be trapped or not. By default
|
|
this will return ``False`` for all exceptions except for a bad request
|
|
key error if ``TRAP_BAD_REQUEST_ERRORS`` is set to ``True``. It
|
|
also returns ``True`` if ``TRAP_HTTP_EXCEPTIONS`` is set to ``True``.
|
|
|
|
This is called for all HTTP exceptions raised by a view function.
|
|
If it returns ``True`` for any exception the error handler for this
|
|
exception is not called and it shows up as regular exception in the
|
|
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
|
|
|
|
trap_bad_request = self.config['TRAP_BAD_REQUEST_ERRORS']
|
|
|
|
# if unset, trap key errors in debug mode
|
|
if (
|
|
trap_bad_request is None and self.debug
|
|
and isinstance(e, BadRequestKeyError)
|
|
):
|
|
return True
|
|
|
|
if trap_bad_request:
|
|
return isinstance(e, BadRequest)
|
|
|
|
return False
|
|
|
|
def handle_user_exception(self, e):
|
|
"""This method is called whenever an exception occurs that
|
|
should be handled. A special case is :class:`~werkzeug
|
|
.exceptions.HTTPException` which is forwarded to the
|
|
:meth:`handle_http_exception` method. This 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
|
|
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.
|
|
|
|
if isinstance(e, BadRequestKeyError):
|
|
if self.debug or self.config["TRAP_BAD_REQUEST_ERRORS"]:
|
|
# Werkzeug < 0.15 doesn't add the KeyError to the 400
|
|
# message, add it in manually.
|
|
description = e.get_description()
|
|
|
|
if e.args[0] not in description:
|
|
e.description = "KeyError: '{}'".format(*e.args)
|
|
else:
|
|
# Werkzeug >= 0.15 does add it, remove it in production
|
|
e.args = ()
|
|
|
|
if isinstance(e, HTTPException) and not self.trap_http_exception(e):
|
|
return self.handle_http_exception(e)
|
|
|
|
handler = self._find_error_handler(e)
|
|
|
|
if handler is None:
|
|
reraise(exc_type, exc_value, tb)
|
|
return handler(e)
|
|
|
|
def handle_exception(self, e):
|
|
"""Default exception handling that kicks in when an exception
|
|
occurs that is not caught. In debug mode the exception will
|
|
be re-raised immediately, otherwise it is logged and the handler
|
|
for a 500 internal server error is used. If no such handler
|
|
exists, a default 500 internal server error message is displayed.
|
|
|
|
.. versionadded:: 0.3
|
|
"""
|
|
exc_type, exc_value, tb = sys.exc_info()
|
|
|
|
got_request_exception.send(self, exception=e)
|
|
handler = self._find_error_handler(InternalServerError())
|
|
|
|
if self.propagate_exceptions:
|
|
# if we want to repropagate the exception, we can attempt to
|
|
# raise it with the whole traceback in case we can do that
|
|
# (the function was actually called from the except part)
|
|
# otherwise, we just raise the error again
|
|
if exc_value is e:
|
|
reraise(exc_type, exc_value, tb)
|
|
else:
|
|
raise e
|
|
|
|
self.log_exception((exc_type, exc_value, tb))
|
|
if handler is None:
|
|
return InternalServerError()
|
|
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`
|
|
if debugging is disabled and right before the handler is called.
|
|
The default implementation logs the exception as error on the
|
|
:attr:`logger`.
|
|
|
|
.. versionadded:: 0.8
|
|
"""
|
|
self.logger.error('Exception on %s [%s]' % (
|
|
request.path,
|
|
request.method
|
|
), exc_info=exc_info)
|
|
|
|
def raise_routing_exception(self, request):
|
|
"""Exceptions that are recording during routing are reraised with
|
|
this method. During debug we are not reraising redirect requests
|
|
for non ``GET``, ``HEAD``, or ``OPTIONS`` requests and we're raising
|
|
a different error instead to help debug situations.
|
|
|
|
:internal:
|
|
"""
|
|
if not self.debug \
|
|
or not isinstance(request.routing_exception, RequestRedirect) \
|
|
or request.method in ('GET', 'HEAD', 'OPTIONS'):
|
|
raise request.routing_exception
|
|
|
|
from .debughelpers import FormDataRoutingRedirect
|
|
raise FormDataRoutingRedirect(request)
|
|
|
|
def dispatch_request(self):
|
|
"""Does the request dispatching. Matches the URL and returns the
|
|
return value of the view or error handler. This does not have to
|
|
be a response object. In order to convert the return value to a
|
|
proper response object, call :func:`make_response`.
|
|
|
|
.. versionchanged:: 0.7
|
|
This no longer does the exception handling, this code was
|
|
moved to the new :meth:`full_dispatch_request`.
|
|
"""
|
|
req = _request_ctx_stack.top.request
|
|
if req.routing_exception is not None:
|
|
self.raise_routing_exception(req)
|
|
rule = req.url_rule
|
|
# if we provide automatic options for this URL and the
|
|
# request came with the OPTIONS method, reply automatically
|
|
if getattr(rule, 'provide_automatic_options', False) \
|
|
and req.method == 'OPTIONS':
|
|
return self.make_default_options_response()
|
|
# otherwise dispatch to the handler for that endpoint
|
|
return self.view_functions[rule.endpoint](**req.view_args)
|
|
|
|
def full_dispatch_request(self):
|
|
"""Dispatches the request and on top of that performs request
|
|
pre and postprocessing as well as HTTP exception catching and
|
|
error handling.
|
|
|
|
.. versionadded:: 0.7
|
|
"""
|
|
self.try_trigger_before_first_request_functions()
|
|
try:
|
|
request_started.send(self)
|
|
rv = self.preprocess_request()
|
|
if rv is None:
|
|
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)
|
|
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):
|
|
"""Called before each request and will ensure that it triggers
|
|
the :attr:`before_first_request_funcs` and only exactly once per
|
|
application instance (which means process usually).
|
|
|
|
:internal:
|
|
"""
|
|
if self._got_first_request:
|
|
return
|
|
with self._before_request_lock:
|
|
if self._got_first_request:
|
|
return
|
|
for func in self.before_first_request_funcs:
|
|
func()
|
|
self._got_first_request = True
|
|
|
|
def make_default_options_response(self):
|
|
"""This method is called to create the default ``OPTIONS`` response.
|
|
This can be changed through subclassing to change the default
|
|
behavior of ``OPTIONS`` responses.
|
|
|
|
.. versionadded:: 0.7
|
|
"""
|
|
adapter = _request_ctx_stack.top.url_adapter
|
|
if hasattr(adapter, 'allowed_methods'):
|
|
methods = adapter.allowed_methods()
|
|
else:
|
|
# fallback for Werkzeug < 0.7
|
|
methods = []
|
|
try:
|
|
adapter.match(method='--')
|
|
except MethodNotAllowed as e:
|
|
methods = e.valid_methods
|
|
except HTTPException as e:
|
|
pass
|
|
rv = self.response_class()
|
|
rv.allow.update(methods)
|
|
return rv
|
|
|
|
def should_ignore_error(self, error):
|
|
"""This is called to figure out if an error should be ignored
|
|
or not as far as the teardown system is concerned. If this
|
|
function returns ``True`` then the teardown handlers will not be
|
|
passed the error.
|
|
|
|
.. versionadded:: 0.10
|
|
"""
|
|
return False
|
|
|
|
def make_response(self, rv):
|
|
"""Convert the return value from a view function to an instance of
|
|
:attr:`response_class`.
|
|
|
|
: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``:
|
|
|
|
``str`` (``unicode`` in Python 2)
|
|
A response object is created with the string encoded to UTF-8
|
|
as the body.
|
|
|
|
``bytes`` (``str`` in Python 2)
|
|
A response object is created with the bytes as the body.
|
|
|
|
``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 = headers = None
|
|
|
|
# unpack tuple returns
|
|
if isinstance(rv, tuple):
|
|
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 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):
|
|
if isinstance(rv, (text_type, bytes, bytearray)):
|
|
# 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:
|
|
# 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])
|
|
|
|
# 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
|
|
|
|
# extend existing headers with provided headers
|
|
if headers:
|
|
rv.headers.extend(headers)
|
|
|
|
return rv
|
|
|
|
def create_url_adapter(self, request):
|
|
"""Creates a URL adapter for the given request. The URL adapter
|
|
is created at a point where the request context is not yet set
|
|
up so the request is passed explicitly.
|
|
|
|
.. versionadded:: 0.6
|
|
|
|
.. versionchanged:: 0.9
|
|
This can now also be called without a request object when the
|
|
URL adapter is created for the application context.
|
|
|
|
.. versionchanged:: 1.0
|
|
:data:`SERVER_NAME` no longer implicitly enables subdomain
|
|
matching. Use :attr:`subdomain_matching` instead.
|
|
"""
|
|
if request is not None:
|
|
# If subdomain matching is disabled (the default), use the
|
|
# default subdomain in all cases. This should be the default
|
|
# in Werkzeug but it currently does not have that feature.
|
|
subdomain = ((self.url_map.default_subdomain or None)
|
|
if not self.subdomain_matching else None)
|
|
return self.url_map.bind_to_environ(
|
|
request.environ,
|
|
server_name=self.config['SERVER_NAME'],
|
|
subdomain=subdomain)
|
|
# We need at the very least the server name to be set for this
|
|
# to work.
|
|
if self.config['SERVER_NAME'] is not None:
|
|
return self.url_map.bind(
|
|
self.config['SERVER_NAME'],
|
|
script_name=self.config['APPLICATION_ROOT'],
|
|
url_scheme=self.config['PREFERRED_URL_SCHEME'])
|
|
|
|
def inject_url_defaults(self, endpoint, values):
|
|
"""Injects the URL defaults for the given endpoint directly into
|
|
the values dictionary passed. This is used internally and
|
|
automatically called on URL building.
|
|
|
|
.. versionadded:: 0.7
|
|
"""
|
|
funcs = self.url_default_functions.get(None, ())
|
|
if '.' in endpoint:
|
|
bp = endpoint.rsplit('.', 1)[0]
|
|
funcs = chain(funcs, self.url_default_functions.get(bp, ()))
|
|
for func in funcs:
|
|
func(endpoint, values)
|
|
|
|
def handle_url_build_error(self, error, endpoint, values):
|
|
"""Handle :class:`~werkzeug.routing.BuildError` on :meth:`url_for`.
|
|
"""
|
|
exc_type, exc_value, tb = sys.exc_info()
|
|
for handler in self.url_build_error_handlers:
|
|
try:
|
|
rv = handler(error, endpoint, values)
|
|
if rv is not None:
|
|
return rv
|
|
except BuildError as e:
|
|
# make error available outside except block (py3)
|
|
error = e
|
|
|
|
# At this point we want to reraise the exception. If the error is
|
|
# still the same one we can reraise it with the original traceback,
|
|
# otherwise we raise it from here.
|
|
if error is exc_value:
|
|
reraise(exc_type, exc_value, tb)
|
|
raise error
|
|
|
|
def preprocess_request(self):
|
|
"""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.
|
|
|
|
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, ())
|
|
if bp is not None and bp in self.url_value_preprocessors:
|
|
funcs = chain(funcs, self.url_value_preprocessors[bp])
|
|
for func in funcs:
|
|
func(request.endpoint, request.view_args)
|
|
|
|
funcs = self.before_request_funcs.get(None, ())
|
|
if bp is not None and bp in self.before_request_funcs:
|
|
funcs = chain(funcs, self.before_request_funcs[bp])
|
|
for func in funcs:
|
|
rv = func()
|
|
if rv is not None:
|
|
return rv
|
|
|
|
def process_response(self, response):
|
|
"""Can be overridden in order to modify the response object
|
|
before it's sent to the WSGI server. By default this will
|
|
call all the :meth:`after_request` decorated functions.
|
|
|
|
.. versionchanged:: 0.5
|
|
As of Flask 0.5 the functions registered for after request
|
|
execution are called in reverse order of registration.
|
|
|
|
:param response: a :attr:`response_class` object.
|
|
:return: a new response object or the same, has to be an
|
|
instance of :attr:`response_class`.
|
|
"""
|
|
ctx = _request_ctx_stack.top
|
|
bp = ctx.request.blueprint
|
|
funcs = ctx._after_request_functions
|
|
if bp is not None and bp in self.after_request_funcs:
|
|
funcs = chain(funcs, reversed(self.after_request_funcs[bp]))
|
|
if None in self.after_request_funcs:
|
|
funcs = chain(funcs, reversed(self.after_request_funcs[None]))
|
|
for handler in funcs:
|
|
response = handler(response)
|
|
if not self.session_interface.is_null_session(ctx.session):
|
|
self.session_interface.save_session(self, ctx.session, response)
|
|
return response
|
|
|
|
def do_teardown_request(self, exc=_sentinel):
|
|
"""Called after the request is dispatched and the response is
|
|
returned, right before the request context is popped.
|
|
|
|
This calls all functions decorated with
|
|
:meth:`teardown_request`, and :meth:`Blueprint.teardown_request`
|
|
if a blueprint handled the request. Finally, the
|
|
:data:`request_tearing_down` signal is sent.
|
|
|
|
This is called by
|
|
:meth:`RequestContext.pop() <flask.ctx.RequestContext.pop>`,
|
|
which may be delayed during testing to maintain access to
|
|
resources.
|
|
|
|
:param exc: An unhandled exception raised while dispatching the
|
|
request. Detected from the current exception information if
|
|
not passed. Passed to each teardown function.
|
|
|
|
.. versionchanged:: 0.9
|
|
Added the ``exc`` argument.
|
|
"""
|
|
if exc is _sentinel:
|
|
exc = sys.exc_info()[1]
|
|
funcs = reversed(self.teardown_request_funcs.get(None, ()))
|
|
bp = _request_ctx_stack.top.request.blueprint
|
|
if bp is not None and bp in self.teardown_request_funcs:
|
|
funcs = chain(funcs, reversed(self.teardown_request_funcs[bp]))
|
|
for func in funcs:
|
|
func(exc)
|
|
request_tearing_down.send(self, exc=exc)
|
|
|
|
def do_teardown_appcontext(self, exc=_sentinel):
|
|
"""Called right before the application context is popped.
|
|
|
|
When handling a request, the application context is popped
|
|
after the request context. See :meth:`do_teardown_request`.
|
|
|
|
This calls all functions decorated with
|
|
:meth:`teardown_appcontext`. Then the
|
|
:data:`appcontext_tearing_down` signal is sent.
|
|
|
|
This is called by
|
|
:meth:`AppContext.pop() <flask.ctx.AppContext.pop>`.
|
|
|
|
.. versionadded:: 0.9
|
|
"""
|
|
if exc is _sentinel:
|
|
exc = sys.exc_info()[1]
|
|
for func in reversed(self.teardown_appcontext_funcs):
|
|
func(exc)
|
|
appcontext_tearing_down.send(self, exc=exc)
|
|
|
|
def app_context(self):
|
|
"""Create an :class:`~flask.ctx.AppContext`. Use as a ``with``
|
|
block to push the context, which will make :data:`current_app`
|
|
point at this application.
|
|
|
|
An application context is automatically pushed by
|
|
:meth:`RequestContext.push() <flask.ctx.RequestContext.push>`
|
|
when handling a request, and when running a CLI command. Use
|
|
this to manually create a context outside of these situations.
|
|
|
|
::
|
|
|
|
with app.app_context():
|
|
init_db()
|
|
|
|
See :doc:`/appcontext`.
|
|
|
|
.. versionadded:: 0.9
|
|
"""
|
|
return AppContext(self)
|
|
|
|
def request_context(self, environ):
|
|
"""Create a :class:`~flask.ctx.RequestContext` representing a
|
|
WSGI environment. Use a ``with`` block to push the context,
|
|
which will make :data:`request` point at this request.
|
|
|
|
See :doc:`/reqcontext`.
|
|
|
|
Typically you should not call this from your own code. A request
|
|
context is automatically pushed by the :meth:`wsgi_app` when
|
|
handling a request. Use :meth:`test_request_context` to create
|
|
an environment and context instead of this method.
|
|
|
|
:param environ: a WSGI environment
|
|
"""
|
|
return RequestContext(self, environ)
|
|
|
|
def test_request_context(self, *args, **kwargs):
|
|
"""Create a :class:`~flask.ctx.RequestContext` for a WSGI
|
|
environment created from the given values. This is mostly useful
|
|
during testing, where you may want to run a function that uses
|
|
request data without dispatching a full request.
|
|
|
|
See :doc:`/reqcontext`.
|
|
|
|
Use a ``with`` block to push the context, which will make
|
|
:data:`request` point at the request for the created
|
|
environment. ::
|
|
|
|
with test_request_context(...):
|
|
generate_report()
|
|
|
|
When using the shell, it may be easier to push and pop the
|
|
context manually to avoid indentation. ::
|
|
|
|
ctx = app.test_request_context(...)
|
|
ctx.push()
|
|
...
|
|
ctx.pop()
|
|
|
|
Takes the same arguments as Werkzeug's
|
|
:class:`~werkzeug.test.EnvironBuilder`, with some defaults from
|
|
the application. See the linked Werkzeug docs for most of the
|
|
available arguments. Flask-specific behavior is listed here.
|
|
|
|
:param path: URL path being requested.
|
|
:param base_url: Base URL where the app is being served, which
|
|
``path`` is relative to. If not given, built from
|
|
:data:`PREFERRED_URL_SCHEME`, ``subdomain``,
|
|
:data:`SERVER_NAME`, and :data:`APPLICATION_ROOT`.
|
|
:param subdomain: Subdomain name to append to
|
|
:data:`SERVER_NAME`.
|
|
:param url_scheme: Scheme to use instead of
|
|
:data:`PREFERRED_URL_SCHEME`.
|
|
:param data: The request body, either as a string or a dict of
|
|
form keys and values.
|
|
:param json: If given, this is serialized as JSON and passed as
|
|
``data``. Also defaults ``content_type`` to
|
|
``application/json``.
|
|
:param args: other positional arguments passed to
|
|
:class:`~werkzeug.test.EnvironBuilder`.
|
|
:param kwargs: other keyword arguments passed to
|
|
:class:`~werkzeug.test.EnvironBuilder`.
|
|
"""
|
|
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:
|
|
builder.close()
|
|
|
|
def wsgi_app(self, environ, start_response):
|
|
"""The actual WSGI application. This is not implemented in
|
|
:meth:`__call__` so that middlewares can be applied without
|
|
losing a reference to the app object. Instead of doing this::
|
|
|
|
app = MyMiddleware(app)
|
|
|
|
It's a better idea to do this instead::
|
|
|
|
app.wsgi_app = MyMiddleware(app.wsgi_app)
|
|
|
|
Then you still have the original application object around and
|
|
can continue to call methods on it.
|
|
|
|
.. versionchanged:: 0.7
|
|
Teardown events for the request and app contexts are called
|
|
even if an unhandled error occurs. Other events may not be
|
|
called depending on when an error occurs during dispatch.
|
|
See :ref:`callbacks-and-errors`.
|
|
|
|
:param environ: A WSGI environment.
|
|
:param start_response: A callable accepting a status code,
|
|
a list of headers, and an optional exception context to
|
|
start the response.
|
|
"""
|
|
ctx = self.request_context(environ)
|
|
error = None
|
|
try:
|
|
try:
|
|
ctx.push()
|
|
response = self.full_dispatch_request()
|
|
except Exception as e:
|
|
error = 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):
|
|
error = None
|
|
ctx.auto_pop(error)
|
|
|
|
def __call__(self, environ, start_response):
|
|
"""The WSGI server calls the Flask application object as the
|
|
WSGI application. This calls :meth:`wsgi_app` which can be
|
|
wrapped to applying middleware."""
|
|
return self.wsgi_app(environ, start_response)
|
|
|
|
def __repr__(self):
|
|
return '<%s %r>' % (
|
|
self.__class__.__name__,
|
|
self.name,
|
|
)
|
|
|