1537 lines
60 KiB
Python
1537 lines
60 KiB
Python
from __future__ import annotations
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import collections.abc as cabc
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import os
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import sys
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import typing as t
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import weakref
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from datetime import timedelta
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from inspect import iscoroutinefunction
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from itertools import chain
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from types import TracebackType
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from urllib.parse import quote as _url_quote
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import click
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from werkzeug.datastructures import Headers
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from werkzeug.datastructures import ImmutableDict
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from werkzeug.exceptions import BadRequestKeyError
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from werkzeug.exceptions import HTTPException
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from werkzeug.exceptions import InternalServerError
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from werkzeug.routing import BuildError
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from werkzeug.routing import MapAdapter
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from werkzeug.routing import RequestRedirect
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from werkzeug.routing import RoutingException
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from werkzeug.routing import Rule
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from werkzeug.serving import is_running_from_reloader
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from werkzeug.wrappers import Response as BaseResponse
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from werkzeug.wsgi import get_host
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from . import cli
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from . import typing as ft
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from .ctx import AppContext
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from .ctx import RequestContext
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from .globals import _cv_app
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from .globals import _cv_request
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from .globals import current_app
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from .globals import g
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from .globals import request
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from .globals import request_ctx
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from .globals import session
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from .helpers import get_debug_flag
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from .helpers import get_flashed_messages
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from .helpers import get_load_dotenv
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from .helpers import send_from_directory
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from .sansio.app import App
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from .sansio.scaffold import _sentinel
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from .sessions import SecureCookieSessionInterface
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from .sessions import SessionInterface
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from .signals import appcontext_tearing_down
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from .signals import got_request_exception
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from .signals import request_finished
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from .signals import request_started
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from .signals import request_tearing_down
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from .templating import Environment
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from .wrappers import Request
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from .wrappers import Response
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if t.TYPE_CHECKING: # pragma: no cover
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from _typeshed.wsgi import StartResponse
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from _typeshed.wsgi import WSGIEnvironment
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from .testing import FlaskClient
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from .testing import FlaskCliRunner
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from .typing import HeadersValue
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T_shell_context_processor = t.TypeVar(
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"T_shell_context_processor", bound=ft.ShellContextProcessorCallable
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)
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T_teardown = t.TypeVar("T_teardown", bound=ft.TeardownCallable)
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T_template_filter = t.TypeVar("T_template_filter", bound=ft.TemplateFilterCallable)
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T_template_global = t.TypeVar("T_template_global", bound=ft.TemplateGlobalCallable)
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T_template_test = t.TypeVar("T_template_test", bound=ft.TemplateTestCallable)
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def _make_timedelta(value: timedelta | int | None) -> timedelta | None:
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if value is None or isinstance(value, timedelta):
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return value
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return timedelta(seconds=value)
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class Flask(App):
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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 is served at
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``static_url_path``. Relative to the application ``root_path``
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or an absolute path. Defaults to ``'static'``.
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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: The path to the root of the application files.
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This should only be set manually when it can't be detected
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automatically, such as for namespace packages.
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"""
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default_config = ImmutableDict(
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{
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"DEBUG": None,
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"TESTING": False,
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"PROPAGATE_EXCEPTIONS": None,
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"SECRET_KEY": None,
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"SECRET_KEY_FALLBACKS": None,
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"PERMANENT_SESSION_LIFETIME": timedelta(days=31),
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"USE_X_SENDFILE": False,
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"TRUSTED_HOSTS": None,
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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_PARTITIONED": 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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"MAX_FORM_MEMORY_SIZE": 500_000,
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"MAX_FORM_PARTS": 1_000,
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"SEND_FILE_MAX_AGE_DEFAULT": None,
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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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"TEMPLATES_AUTO_RELOAD": None,
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"MAX_COOKIE_SIZE": 4093,
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"PROVIDE_AUTOMATIC_OPTIONS": True,
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}
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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: type[Request] = 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: type[Response] = Response
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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: SessionInterface = SecureCookieSessionInterface()
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def __init__(
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self,
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import_name: str,
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static_url_path: str | None = None,
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static_folder: str | os.PathLike[str] | None = "static",
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static_host: str | None = None,
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host_matching: bool = False,
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subdomain_matching: bool = False,
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template_folder: str | os.PathLike[str] | None = "templates",
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instance_path: str | None = None,
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instance_relative_config: bool = False,
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root_path: str | None = None,
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):
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super().__init__(
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import_name=import_name,
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static_url_path=static_url_path,
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static_folder=static_folder,
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static_host=static_host,
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host_matching=host_matching,
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subdomain_matching=subdomain_matching,
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template_folder=template_folder,
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instance_path=instance_path,
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instance_relative_config=instance_relative_config,
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root_path=root_path,
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)
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#: The Click command group for registering CLI commands for this
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#: object. The commands are available from the ``flask`` command
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#: once the application has been discovered and blueprints have
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#: been registered.
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self.cli = cli.AppGroup()
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# Set the name of the Click group in case someone wants to add
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# the app's commands to another CLI tool.
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self.cli.name = self.name
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# Add a static route using the provided static_url_path, static_host,
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# and static_folder if there is a configured static_folder.
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# Note we do this without checking if static_folder exists.
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# For one, it might be created while the server is running (e.g. during
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# development). Also, Google App Engine stores static files somewhere
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if self.has_static_folder:
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assert bool(static_host) == host_matching, (
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"Invalid static_host/host_matching combination"
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)
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# Use a weakref to avoid creating a reference cycle between the app
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# and the view function (see #3761).
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self_ref = weakref.ref(self)
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self.add_url_rule(
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f"{self.static_url_path}/<path:filename>",
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endpoint="static",
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host=static_host,
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view_func=lambda **kw: self_ref().send_static_file(**kw), # type: ignore # noqa: B950
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)
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def get_send_file_max_age(self, filename: str | None) -> int | None:
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"""Used by :func:`send_file` to determine the ``max_age`` cache
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value for a given file path if it wasn't passed.
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By default, this returns :data:`SEND_FILE_MAX_AGE_DEFAULT` from
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the configuration of :data:`~flask.current_app`. This defaults
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to ``None``, which tells the browser to use conditional requests
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instead of a timed cache, which is usually preferable.
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Note this is a duplicate of the same method in the Flask
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class.
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.. versionchanged:: 2.0
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The default configuration is ``None`` instead of 12 hours.
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.. versionadded:: 0.9
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"""
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value = current_app.config["SEND_FILE_MAX_AGE_DEFAULT"]
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if value is None:
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return None
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if isinstance(value, timedelta):
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return int(value.total_seconds())
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return value # type: ignore[no-any-return]
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def send_static_file(self, filename: str) -> Response:
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"""The view function used to serve files from
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:attr:`static_folder`. A route is automatically registered for
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this view at :attr:`static_url_path` if :attr:`static_folder` is
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set.
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Note this is a duplicate of the same method in the Flask
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class.
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.. versionadded:: 0.5
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"""
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if not self.has_static_folder:
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raise RuntimeError("'static_folder' must be set to serve static_files.")
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# send_file only knows to call get_send_file_max_age on the app,
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# call it here so it works for blueprints too.
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max_age = self.get_send_file_max_age(filename)
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return send_from_directory(
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t.cast(str, self.static_folder), filename, max_age=max_age
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)
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def open_resource(
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self, resource: str, mode: str = "rb", encoding: str | None = None
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) -> t.IO[t.AnyStr]:
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"""Open a resource file relative to :attr:`root_path` for reading.
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For example, if the file ``schema.sql`` is next to the file
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``app.py`` where the ``Flask`` app is defined, it can be opened
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with:
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.. code-block:: python
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with app.open_resource("schema.sql") as f:
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conn.executescript(f.read())
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:param resource: Path to the resource relative to :attr:`root_path`.
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:param mode: Open the file in this mode. Only reading is supported,
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valid values are ``"r"`` (or ``"rt"``) and ``"rb"``.
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:param encoding: Open the file with this encoding when opening in text
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mode. This is ignored when opening in binary mode.
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.. versionchanged:: 3.1
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Added the ``encoding`` parameter.
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"""
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if mode not in {"r", "rt", "rb"}:
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raise ValueError("Resources can only be opened for reading.")
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path = os.path.join(self.root_path, resource)
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if mode == "rb":
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return open(path, mode) # pyright: ignore
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return open(path, mode, encoding=encoding)
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def open_instance_resource(
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self, resource: str, mode: str = "rb", encoding: str | None = "utf-8"
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) -> t.IO[t.AnyStr]:
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"""Open a resource file relative to the application's instance folder
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:attr:`instance_path`. Unlike :meth:`open_resource`, files in the
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instance folder can be opened for writing.
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:param resource: Path to the resource relative to :attr:`instance_path`.
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:param mode: Open the file in this mode.
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:param encoding: Open the file with this encoding when opening in text
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mode. This is ignored when opening in binary mode.
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.. versionchanged:: 3.1
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Added the ``encoding`` parameter.
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"""
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path = os.path.join(self.instance_path, resource)
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if "b" in mode:
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return open(path, mode)
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return open(path, mode, encoding=encoding)
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def create_jinja_environment(self) -> Environment:
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"""Create the Jinja environment based on :attr:`jinja_options`
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and the various Jinja-related methods of the app. Changing
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:attr:`jinja_options` after this will have no effect. Also adds
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Flask-related globals and filters to the environment.
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.. versionchanged:: 0.11
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``Environment.auto_reload`` set in accordance with
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``TEMPLATES_AUTO_RELOAD`` configuration option.
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.. versionadded:: 0.5
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"""
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options = dict(self.jinja_options)
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if "autoescape" not in options:
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options["autoescape"] = self.select_jinja_autoescape
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if "auto_reload" not in options:
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auto_reload = self.config["TEMPLATES_AUTO_RELOAD"]
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if auto_reload is None:
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auto_reload = self.debug
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options["auto_reload"] = auto_reload
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rv = self.jinja_environment(self, **options)
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rv.globals.update(
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url_for=self.url_for,
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get_flashed_messages=get_flashed_messages,
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config=self.config,
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# request, session and g are normally added with the
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# context processor for efficiency reasons but for imported
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# templates we also want the proxies in there.
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request=request,
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session=session,
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g=g,
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)
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rv.policies["json.dumps_function"] = self.json.dumps
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return rv
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def create_url_adapter(self, request: Request | None) -> MapAdapter | None:
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"""Creates a URL adapter for the given request. The URL adapter
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is created at a point where the request context is not yet set
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up so the request is passed explicitly.
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.. versionchanged:: 3.1
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If :data:`SERVER_NAME` is set, it does not restrict requests to
|
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only that domain, for both ``subdomain_matching`` and
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``host_matching``.
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|
.. versionchanged:: 1.0
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|
:data:`SERVER_NAME` no longer implicitly enables subdomain
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matching. Use :attr:`subdomain_matching` instead.
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|
|
.. versionchanged:: 0.9
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This can be called outside a request when the URL adapter is created
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for an application context.
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.. versionadded:: 0.6
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"""
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if request is not None:
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if (trusted_hosts := self.config["TRUSTED_HOSTS"]) is not None:
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request.trusted_hosts = trusted_hosts
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# Check trusted_hosts here until bind_to_environ does.
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request.host = get_host(request.environ, request.trusted_hosts) # pyright: ignore
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subdomain = None
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server_name = self.config["SERVER_NAME"]
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if self.url_map.host_matching:
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# Don't pass SERVER_NAME, otherwise it's used and the actual
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# host is ignored, which breaks host matching.
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server_name = None
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elif not self.subdomain_matching:
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# Werkzeug doesn't implement subdomain matching yet. Until then,
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# disable it by forcing the current subdomain to the default, or
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# the empty string.
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subdomain = self.url_map.default_subdomain or ""
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return self.url_map.bind_to_environ(
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request.environ, server_name=server_name, subdomain=subdomain
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)
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# Need at least SERVER_NAME to match/build outside a request.
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if self.config["SERVER_NAME"] is not None:
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return self.url_map.bind(
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self.config["SERVER_NAME"],
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script_name=self.config["APPLICATION_ROOT"],
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url_scheme=self.config["PREFERRED_URL_SCHEME"],
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)
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return None
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|
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def raise_routing_exception(self, request: Request) -> t.NoReturn:
|
|
"""Intercept routing exceptions and possibly do something else.
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|
|
In debug mode, intercept a routing redirect and replace it with
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an error if the body will be discarded.
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With modern Werkzeug this shouldn't occur, since it now uses a
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308 status which tells the browser to resend the method and
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body.
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.. versionchanged:: 2.1
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|
Don't intercept 307 and 308 redirects.
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:meta private:
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:internal:
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"""
|
|
if (
|
|
not self.debug
|
|
or not isinstance(request.routing_exception, RequestRedirect)
|
|
or request.routing_exception.code in {307, 308}
|
|
or request.method in {"GET", "HEAD", "OPTIONS"}
|
|
):
|
|
raise request.routing_exception # type: ignore[misc]
|
|
|
|
from .debughelpers import FormDataRoutingRedirect
|
|
|
|
raise FormDataRoutingRedirect(request)
|
|
|
|
def update_template_context(self, context: dict[str, t.Any]) -> None:
|
|
"""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.
|
|
"""
|
|
names: t.Iterable[str | None] = (None,)
|
|
|
|
# A template may be rendered outside a request context.
|
|
if request:
|
|
names = chain(names, reversed(request.blueprints))
|
|
|
|
# The values passed to render_template take precedence. Keep a
|
|
# copy to re-apply after all context functions.
|
|
orig_ctx = context.copy()
|
|
|
|
for name in names:
|
|
if name in self.template_context_processors:
|
|
for func in self.template_context_processors[name]:
|
|
context.update(self.ensure_sync(func)())
|
|
|
|
context.update(orig_ctx)
|
|
|
|
def make_shell_context(self) -> dict[str, t.Any]:
|
|
"""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
|
|
|
|
def run(
|
|
self,
|
|
host: str | None = None,
|
|
port: int | None = None,
|
|
debug: bool | None = None,
|
|
load_dotenv: bool = True,
|
|
**options: t.Any,
|
|
) -> None:
|
|
"""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 :doc:`/deploying/index` 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.
|
|
|
|
The :envvar:`FLASK_DEBUG` environment variable will override :attr:`debug`.
|
|
|
|
Threaded mode is enabled by default.
|
|
|
|
.. versionchanged:: 0.10
|
|
The default port is now picked from the ``SERVER_NAME``
|
|
variable.
|
|
"""
|
|
# Ignore this call so that it doesn't start another server if
|
|
# the 'flask run' command is used.
|
|
if os.environ.get("FLASK_RUN_FROM_CLI") == "true":
|
|
if not is_running_from_reloader():
|
|
click.secho(
|
|
" * Ignoring a call to 'app.run()' that would block"
|
|
" the current 'flask' CLI command.\n"
|
|
" Only call 'app.run()' in an 'if __name__ =="
|
|
' "__main__"\' guard.',
|
|
fg="red",
|
|
)
|
|
|
|
return
|
|
|
|
if get_load_dotenv(load_dotenv):
|
|
cli.load_dotenv()
|
|
|
|
# if set, env var overrides existing value
|
|
if "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)
|
|
|
|
server_name = self.config.get("SERVER_NAME")
|
|
sn_host = sn_port = None
|
|
|
|
if server_name:
|
|
sn_host, _, sn_port = server_name.partition(":")
|
|
|
|
if not host:
|
|
if sn_host:
|
|
host = sn_host
|
|
else:
|
|
host = "127.0.0.1"
|
|
|
|
if port or port == 0:
|
|
port = int(port)
|
|
elif sn_port:
|
|
port = int(sn_port)
|
|
else:
|
|
port = 5000
|
|
|
|
options.setdefault("use_reloader", self.debug)
|
|
options.setdefault("use_debugger", self.debug)
|
|
options.setdefault("threaded", True)
|
|
|
|
cli.show_server_banner(self.debug, self.name)
|
|
|
|
from werkzeug.serving import run_simple
|
|
|
|
try:
|
|
run_simple(t.cast(str, 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: bool = True, **kwargs: t.Any) -> FlaskClient:
|
|
"""Creates a test client for this application. For information
|
|
about unit testing head over to :doc:`/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::
|
|
|
|
from flask.testing import FlaskClient
|
|
|
|
class CustomClient(FlaskClient):
|
|
def __init__(self, *args, **kwargs):
|
|
self._authentication = kwargs.pop("authentication")
|
|
super(CustomClient,self).__init__( *args, **kwargs)
|
|
|
|
app.test_client_class = CustomClient
|
|
client = app.test_client(authentication='Basic ....')
|
|
|
|
See :class:`~flask.testing.FlaskClient` for more information.
|
|
|
|
.. versionchanged:: 0.4
|
|
added support for ``with`` block usage for the client.
|
|
|
|
.. versionadded:: 0.7
|
|
The `use_cookies` parameter was added as well as the ability
|
|
to override the client to be used by setting the
|
|
:attr:`test_client_class` attribute.
|
|
|
|
.. versionchanged:: 0.11
|
|
Added `**kwargs` to support passing additional keyword arguments to
|
|
the constructor of :attr:`test_client_class`.
|
|
"""
|
|
cls = self.test_client_class
|
|
if cls is None:
|
|
from .testing import FlaskClient as cls
|
|
return cls( # type: ignore
|
|
self, self.response_class, use_cookies=use_cookies, **kwargs
|
|
)
|
|
|
|
def test_cli_runner(self, **kwargs: t.Any) -> FlaskCliRunner:
|
|
"""Create a CLI runner for testing CLI commands.
|
|
See :ref:`testing-cli`.
|
|
|
|
Returns an instance of :attr:`test_cli_runner_class`, by default
|
|
:class:`~flask.testing.FlaskCliRunner`. The Flask app object is
|
|
passed as the first argument.
|
|
|
|
.. versionadded:: 1.0
|
|
"""
|
|
cls = self.test_cli_runner_class
|
|
|
|
if cls is None:
|
|
from .testing import FlaskCliRunner as cls
|
|
|
|
return cls(self, **kwargs) # type: ignore
|
|
|
|
def handle_http_exception(
|
|
self, e: HTTPException
|
|
) -> HTTPException | ft.ResponseReturnValue:
|
|
"""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
|
|
``HTTPException`` 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, request.blueprints)
|
|
if handler is None:
|
|
return e
|
|
return self.ensure_sync(handler)(e) # type: ignore[no-any-return]
|
|
|
|
def handle_user_exception(
|
|
self, e: Exception
|
|
) -> HTTPException | ft.ResponseReturnValue:
|
|
"""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
|
|
"""
|
|
if isinstance(e, BadRequestKeyError) and (
|
|
self.debug or self.config["TRAP_BAD_REQUEST_ERRORS"]
|
|
):
|
|
e.show_exception = True
|
|
|
|
if isinstance(e, HTTPException) and not self.trap_http_exception(e):
|
|
return self.handle_http_exception(e)
|
|
|
|
handler = self._find_error_handler(e, request.blueprints)
|
|
|
|
if handler is None:
|
|
raise
|
|
|
|
return self.ensure_sync(handler)(e) # type: ignore[no-any-return]
|
|
|
|
def handle_exception(self, e: Exception) -> Response:
|
|
"""Handle an exception that did not have an error handler
|
|
associated with it, or that was raised from an error handler.
|
|
This always causes a 500 ``InternalServerError``.
|
|
|
|
Always sends the :data:`got_request_exception` signal.
|
|
|
|
If :data:`PROPAGATE_EXCEPTIONS` is ``True``, such as in debug
|
|
mode, the error will be re-raised so that the debugger can
|
|
display it. Otherwise, the original exception is logged, and
|
|
an :exc:`~werkzeug.exceptions.InternalServerError` is returned.
|
|
|
|
If an error handler is registered for ``InternalServerError`` or
|
|
``500``, it will be used. For consistency, the handler will
|
|
always receive the ``InternalServerError``. The original
|
|
unhandled exception is available as ``e.original_exception``.
|
|
|
|
.. versionchanged:: 1.1.0
|
|
Always passes the ``InternalServerError`` instance to the
|
|
handler, setting ``original_exception`` to the unhandled
|
|
error.
|
|
|
|
.. versionchanged:: 1.1.0
|
|
``after_request`` functions and other finalization is done
|
|
even for the default 500 response when there is no handler.
|
|
|
|
.. versionadded:: 0.3
|
|
"""
|
|
exc_info = sys.exc_info()
|
|
got_request_exception.send(self, _async_wrapper=self.ensure_sync, exception=e)
|
|
propagate = self.config["PROPAGATE_EXCEPTIONS"]
|
|
|
|
if propagate is None:
|
|
propagate = self.testing or self.debug
|
|
|
|
if propagate:
|
|
# Re-raise if called with an active exception, otherwise
|
|
# raise the passed in exception.
|
|
if exc_info[1] is e:
|
|
raise
|
|
|
|
raise e
|
|
|
|
self.log_exception(exc_info)
|
|
server_error: InternalServerError | ft.ResponseReturnValue
|
|
server_error = InternalServerError(original_exception=e)
|
|
handler = self._find_error_handler(server_error, request.blueprints)
|
|
|
|
if handler is not None:
|
|
server_error = self.ensure_sync(handler)(server_error)
|
|
|
|
return self.finalize_request(server_error, from_error_handler=True)
|
|
|
|
def log_exception(
|
|
self,
|
|
exc_info: (tuple[type, BaseException, TracebackType] | tuple[None, None, None]),
|
|
) -> None:
|
|
"""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(
|
|
f"Exception on {request.path} [{request.method}]", exc_info=exc_info
|
|
)
|
|
|
|
def dispatch_request(self) -> ft.ResponseReturnValue:
|
|
"""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.request
|
|
if req.routing_exception is not None:
|
|
self.raise_routing_exception(req)
|
|
rule: Rule = req.url_rule # type: ignore[assignment]
|
|
# 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
|
|
view_args: dict[str, t.Any] = req.view_args # type: ignore[assignment]
|
|
return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args) # type: ignore[no-any-return]
|
|
|
|
def full_dispatch_request(self) -> Response:
|
|
"""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._got_first_request = True
|
|
|
|
try:
|
|
request_started.send(self, _async_wrapper=self.ensure_sync)
|
|
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: ft.ResponseReturnValue | HTTPException,
|
|
from_error_handler: bool = False,
|
|
) -> Response:
|
|
"""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, _async_wrapper=self.ensure_sync, 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 make_default_options_response(self) -> Response:
|
|
"""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.url_adapter
|
|
methods = adapter.allowed_methods() # type: ignore[union-attr]
|
|
rv = self.response_class()
|
|
rv.allow.update(methods)
|
|
return rv
|
|
|
|
def ensure_sync(self, func: t.Callable[..., t.Any]) -> t.Callable[..., t.Any]:
|
|
"""Ensure that the function is synchronous for WSGI workers.
|
|
Plain ``def`` functions are returned as-is. ``async def``
|
|
functions are wrapped to run and wait for the response.
|
|
|
|
Override this method to change how the app runs async views.
|
|
|
|
.. versionadded:: 2.0
|
|
"""
|
|
if iscoroutinefunction(func):
|
|
return self.async_to_sync(func)
|
|
|
|
return func
|
|
|
|
def async_to_sync(
|
|
self, func: t.Callable[..., t.Coroutine[t.Any, t.Any, t.Any]]
|
|
) -> t.Callable[..., t.Any]:
|
|
"""Return a sync function that will run the coroutine function.
|
|
|
|
.. code-block:: python
|
|
|
|
result = app.async_to_sync(func)(*args, **kwargs)
|
|
|
|
Override this method to change how the app converts async code
|
|
to be synchronously callable.
|
|
|
|
.. versionadded:: 2.0
|
|
"""
|
|
try:
|
|
from asgiref.sync import async_to_sync as asgiref_async_to_sync
|
|
except ImportError:
|
|
raise RuntimeError(
|
|
"Install Flask with the 'async' extra in order to use async views."
|
|
) from None
|
|
|
|
return asgiref_async_to_sync(func)
|
|
|
|
def url_for(
|
|
self,
|
|
/,
|
|
endpoint: str,
|
|
*,
|
|
_anchor: str | None = None,
|
|
_method: str | None = None,
|
|
_scheme: str | None = None,
|
|
_external: bool | None = None,
|
|
**values: t.Any,
|
|
) -> str:
|
|
"""Generate a URL to the given endpoint with the given values.
|
|
|
|
This is called by :func:`flask.url_for`, and can be called
|
|
directly as well.
|
|
|
|
An *endpoint* is the name of a URL rule, usually added with
|
|
:meth:`@app.route() <route>`, and usually the same name as the
|
|
view function. A route defined in a :class:`~flask.Blueprint`
|
|
will prepend the blueprint's name separated by a ``.`` to the
|
|
endpoint.
|
|
|
|
In some cases, such as email messages, you want URLs to include
|
|
the scheme and domain, like ``https://example.com/hello``. When
|
|
not in an active request, URLs will be external by default, but
|
|
this requires setting :data:`SERVER_NAME` so Flask knows what
|
|
domain to use. :data:`APPLICATION_ROOT` and
|
|
:data:`PREFERRED_URL_SCHEME` should also be configured as
|
|
needed. This config is only used when not in an active request.
|
|
|
|
Functions can be decorated with :meth:`url_defaults` to modify
|
|
keyword arguments before the URL is built.
|
|
|
|
If building fails for some reason, such as an unknown endpoint
|
|
or incorrect values, the app's :meth:`handle_url_build_error`
|
|
method is called. If that returns a string, that is returned,
|
|
otherwise a :exc:`~werkzeug.routing.BuildError` is raised.
|
|
|
|
:param endpoint: The endpoint name associated with the URL to
|
|
generate. If this starts with a ``.``, the current blueprint
|
|
name (if any) will be used.
|
|
:param _anchor: If given, append this as ``#anchor`` to the URL.
|
|
:param _method: If given, generate the URL associated with this
|
|
method for the endpoint.
|
|
:param _scheme: If given, the URL will have this scheme if it
|
|
is external.
|
|
:param _external: If given, prefer the URL to be internal
|
|
(False) or require it to be external (True). External URLs
|
|
include the scheme and domain. When not in an active
|
|
request, URLs are external by default.
|
|
:param values: Values to use for the variable parts of the URL
|
|
rule. Unknown keys are appended as query string arguments,
|
|
like ``?a=b&c=d``.
|
|
|
|
.. versionadded:: 2.2
|
|
Moved from ``flask.url_for``, which calls this method.
|
|
"""
|
|
req_ctx = _cv_request.get(None)
|
|
|
|
if req_ctx is not None:
|
|
url_adapter = req_ctx.url_adapter
|
|
blueprint_name = req_ctx.request.blueprint
|
|
|
|
# If the endpoint starts with "." and the request matches a
|
|
# blueprint, the endpoint is relative to the blueprint.
|
|
if endpoint[:1] == ".":
|
|
if blueprint_name is not None:
|
|
endpoint = f"{blueprint_name}{endpoint}"
|
|
else:
|
|
endpoint = endpoint[1:]
|
|
|
|
# When in a request, generate a URL without scheme and
|
|
# domain by default, unless a scheme is given.
|
|
if _external is None:
|
|
_external = _scheme is not None
|
|
else:
|
|
app_ctx = _cv_app.get(None)
|
|
|
|
# If called by helpers.url_for, an app context is active,
|
|
# use its url_adapter. Otherwise, app.url_for was called
|
|
# directly, build an adapter.
|
|
if app_ctx is not None:
|
|
url_adapter = app_ctx.url_adapter
|
|
else:
|
|
url_adapter = self.create_url_adapter(None)
|
|
|
|
if url_adapter is None:
|
|
raise RuntimeError(
|
|
"Unable to build URLs outside an active request"
|
|
" without 'SERVER_NAME' configured. Also configure"
|
|
" 'APPLICATION_ROOT' and 'PREFERRED_URL_SCHEME' as"
|
|
" needed."
|
|
)
|
|
|
|
# When outside a request, generate a URL with scheme and
|
|
# domain by default.
|
|
if _external is None:
|
|
_external = True
|
|
|
|
# It is an error to set _scheme when _external=False, in order
|
|
# to avoid accidental insecure URLs.
|
|
if _scheme is not None and not _external:
|
|
raise ValueError("When specifying '_scheme', '_external' must be True.")
|
|
|
|
self.inject_url_defaults(endpoint, values)
|
|
|
|
try:
|
|
rv = url_adapter.build( # type: ignore[union-attr]
|
|
endpoint,
|
|
values,
|
|
method=_method,
|
|
url_scheme=_scheme,
|
|
force_external=_external,
|
|
)
|
|
except BuildError as error:
|
|
values.update(
|
|
_anchor=_anchor, _method=_method, _scheme=_scheme, _external=_external
|
|
)
|
|
return self.handle_url_build_error(error, endpoint, values)
|
|
|
|
if _anchor is not None:
|
|
_anchor = _url_quote(_anchor, safe="%!#$&'()*+,/:;=?@")
|
|
rv = f"{rv}#{_anchor}"
|
|
|
|
return rv
|
|
|
|
def make_response(self, rv: ft.ResponseReturnValue) -> Response:
|
|
"""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``
|
|
A response object is created with the string encoded to UTF-8
|
|
as the body.
|
|
|
|
``bytes``
|
|
A response object is created with the bytes as the body.
|
|
|
|
``dict``
|
|
A dictionary that will be jsonify'd before being returned.
|
|
|
|
``list``
|
|
A list that will be jsonify'd before being returned.
|
|
|
|
``generator`` or ``iterator``
|
|
A generator that returns ``str`` or ``bytes`` to be
|
|
streamed as the response.
|
|
|
|
``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:: 2.2
|
|
A generator will be converted to a streaming response.
|
|
A list will be converted to a JSON response.
|
|
|
|
.. versionchanged:: 1.1
|
|
A dict will be converted to a JSON response.
|
|
|
|
.. versionchanged:: 0.9
|
|
Previously a tuple was interpreted as the arguments for the
|
|
response object.
|
|
"""
|
|
|
|
status: int | None = None
|
|
headers: HeadersValue | None = 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 # type: ignore[misc]
|
|
# decide if a 2-tuple has status or headers
|
|
elif len_rv == 2:
|
|
if isinstance(rv[1], (Headers, dict, tuple, list)):
|
|
rv, headers = rv # pyright: ignore
|
|
else:
|
|
rv, status = rv # type: ignore[assignment,misc]
|
|
# 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(
|
|
f"The view function for {request.endpoint!r} 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, (str, bytes, bytearray)) or isinstance(rv, cabc.Iterator):
|
|
# 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, # pyright: ignore
|
|
status=status,
|
|
headers=headers, # type: ignore[arg-type]
|
|
)
|
|
status = headers = None
|
|
elif isinstance(rv, (dict, list)):
|
|
rv = self.json.response(rv)
|
|
elif isinstance(rv, BaseResponse) or callable(rv):
|
|
# evaluate a WSGI callable, or coerce a different response
|
|
# class to the correct type
|
|
try:
|
|
rv = self.response_class.force_type(
|
|
rv, # type: ignore[arg-type]
|
|
request.environ,
|
|
)
|
|
except TypeError as e:
|
|
raise TypeError(
|
|
f"{e}\nThe view function did not return a valid"
|
|
" response. The return type must be a string,"
|
|
" dict, list, tuple with headers or status,"
|
|
" Response instance, or WSGI callable, but it"
|
|
f" was a {type(rv).__name__}."
|
|
).with_traceback(sys.exc_info()[2]) from None
|
|
else:
|
|
raise TypeError(
|
|
"The view function did not return a valid"
|
|
" response. The return type must be a string,"
|
|
" dict, list, tuple with headers or status,"
|
|
" Response instance, or WSGI callable, but it was a"
|
|
f" {type(rv).__name__}."
|
|
)
|
|
|
|
rv = t.cast(Response, rv)
|
|
# prefer the status if it was provided
|
|
if status is not None:
|
|
if isinstance(status, (str, bytes, bytearray)):
|
|
rv.status = status
|
|
else:
|
|
rv.status_code = status
|
|
|
|
# extend existing headers with provided headers
|
|
if headers:
|
|
rv.headers.update(headers)
|
|
|
|
return rv
|
|
|
|
def preprocess_request(self) -> ft.ResponseReturnValue | None:
|
|
"""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.
|
|
"""
|
|
names = (None, *reversed(request.blueprints))
|
|
|
|
for name in names:
|
|
if name in self.url_value_preprocessors:
|
|
for url_func in self.url_value_preprocessors[name]:
|
|
url_func(request.endpoint, request.view_args)
|
|
|
|
for name in names:
|
|
if name in self.before_request_funcs:
|
|
for before_func in self.before_request_funcs[name]:
|
|
rv = self.ensure_sync(before_func)()
|
|
|
|
if rv is not None:
|
|
return rv # type: ignore[no-any-return]
|
|
|
|
return None
|
|
|
|
def process_response(self, response: Response) -> 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._get_current_object() # type: ignore[attr-defined]
|
|
|
|
for func in ctx._after_request_functions:
|
|
response = self.ensure_sync(func)(response)
|
|
|
|
for name in chain(request.blueprints, (None,)):
|
|
if name in self.after_request_funcs:
|
|
for func in reversed(self.after_request_funcs[name]):
|
|
response = self.ensure_sync(func)(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: BaseException | None = _sentinel, # type: ignore[assignment]
|
|
) -> None:
|
|
"""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]
|
|
|
|
for name in chain(request.blueprints, (None,)):
|
|
if name in self.teardown_request_funcs:
|
|
for func in reversed(self.teardown_request_funcs[name]):
|
|
self.ensure_sync(func)(exc)
|
|
|
|
request_tearing_down.send(self, _async_wrapper=self.ensure_sync, exc=exc)
|
|
|
|
def do_teardown_appcontext(
|
|
self,
|
|
exc: BaseException | None = _sentinel, # type: ignore[assignment]
|
|
) -> None:
|
|
"""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):
|
|
self.ensure_sync(func)(exc)
|
|
|
|
appcontext_tearing_down.send(self, _async_wrapper=self.ensure_sync, exc=exc)
|
|
|
|
def app_context(self) -> AppContext:
|
|
"""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: WSGIEnvironment) -> RequestContext:
|
|
"""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: t.Any, **kwargs: t.Any) -> RequestContext:
|
|
"""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 app.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 .testing import EnvironBuilder
|
|
|
|
builder = EnvironBuilder(self, *args, **kwargs)
|
|
|
|
try:
|
|
return self.request_context(builder.get_environ())
|
|
finally:
|
|
builder.close()
|
|
|
|
def wsgi_app(
|
|
self, environ: WSGIEnvironment, start_response: StartResponse
|
|
) -> cabc.Iterable[bytes]:
|
|
"""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: BaseException | None = None
|
|
try:
|
|
try:
|
|
ctx.push()
|
|
response = self.full_dispatch_request()
|
|
except Exception as e:
|
|
error = e
|
|
response = self.handle_exception(e)
|
|
except: # noqa: B001
|
|
error = sys.exc_info()[1]
|
|
raise
|
|
return response(environ, start_response)
|
|
finally:
|
|
if "werkzeug.debug.preserve_context" in environ:
|
|
environ["werkzeug.debug.preserve_context"](_cv_app.get())
|
|
environ["werkzeug.debug.preserve_context"](_cv_request.get())
|
|
|
|
if error is not None and self.should_ignore_error(error):
|
|
error = None
|
|
|
|
ctx.pop(error)
|
|
|
|
def __call__(
|
|
self, environ: WSGIEnvironment, start_response: StartResponse
|
|
) -> cabc.Iterable[bytes]:
|
|
"""The WSGI server calls the Flask application object as the
|
|
WSGI application. This calls :meth:`wsgi_app`, which can be
|
|
wrapped to apply middleware.
|
|
"""
|
|
return self.wsgi_app(environ, start_response)
|