Remove submodule, just put Dependencies in ./libs
This commit is contained in:
@@ -0,0 +1,965 @@
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# -*- 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: (c) 2010 by Armin Ronacher.
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:license: BSD, see LICENSE for more details.
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"""
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from __future__ import with_statement
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from threading import Lock
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from datetime import timedelta, datetime
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from itertools import chain
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from jinja2 import Environment
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from werkzeug import ImmutableDict
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from werkzeug.routing import Map, Rule
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from werkzeug.exceptions import HTTPException, InternalServerError, \
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MethodNotAllowed
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from .helpers import _PackageBoundObject, url_for, get_flashed_messages, \
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_tojson_filter, _endpoint_from_view_func
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from .wrappers import Request, Response
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from .config import ConfigAttribute, Config
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from .ctx import _RequestContext
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from .globals import _request_ctx_stack, request
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from .session import Session, _NullSession
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from .module import _ModuleSetupState
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from .templating import _DispatchingJinjaLoader, \
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_default_template_ctx_processor
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from .signals import request_started, request_finished, got_request_exception
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# a lock used for logger initialization
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_logger_lock = Lock()
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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 `__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 `__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 what
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belongs to your application. This name is used to find resources
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on the file system, 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 `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 `yourapplicaiton.app` and not
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`yourapplication.views.frontend`)
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.. versionadded:: 0.5
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The `static_path` parameter was added.
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:param import_name: the name of the application package
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:param static_path: can be used to specify a different path for the
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static files on the web. Defaults to ``/static``.
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This does not affect the folder the files are served
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*from*.
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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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#: Path for the static files. If you don't want to use static files
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#: you can set this value to `None` in which case no URL rule is added
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#: and the development server will no longer serve any static files.
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#:
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#: This is the default used for application and modules unless a
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#: different value is passed to the constructor.
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static_path = '/static'
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#: The debug flag. Set this to `True` to enable debugging of the
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#: application. In debug mode the debugger will kick in when an unhandled
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#: exception ocurrs and the integrated server will automatically reload
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#: the application if changes in the code are detected.
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#:
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#: This attribute can also be configured from the config with the `DEBUG`
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#: configuration key. Defaults to `False`.
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debug = ConfigAttribute('DEBUG')
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#: The testing flask. 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 unittest 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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#: 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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#: `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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#: 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 name of the logger to use. By default the logger name is the
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#: package name passed to the constructor.
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#:
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#: .. versionadded:: 0.4
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logger_name = ConfigAttribute('LOGGER_NAME')
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#: The logging format used for the debug logger. This is only used when
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#: the application is in debug mode, otherwise the attached logging
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#: handler does the formatting.
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#:
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#: .. versionadded:: 0.3
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debug_log_format = (
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'-' * 80 + '\n' +
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'%(levelname)s in %(module)s [%(pathname)s:%(lineno)d]:\n' +
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'%(message)s\n' +
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'-' * 80
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)
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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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'DEBUG': False,
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'TESTING': False,
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'PROPAGATE_EXCEPTIONS': None,
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'SECRET_KEY': None,
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'SESSION_COOKIE_NAME': 'session',
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'PERMANENT_SESSION_LIFETIME': timedelta(days=31),
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'USE_X_SENDFILE': False,
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'LOGGER_NAME': None,
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'SERVER_NAME': None,
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'MAX_CONTENT_LENGTH': None
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})
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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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def __init__(self, import_name, static_path=None):
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_PackageBoundObject.__init__(self, import_name)
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if static_path is not None:
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self.static_path = static_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 = Config(self.root_path, self.default_config)
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#: Prepare the deferred setup of the logger.
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self._logger = None
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self.logger_name = self.import_name
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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
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#: be the error code as integer, the value the function that
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#: should handle that error.
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#: To register a error handler, use the :meth:`errorhandler`
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#: decorator.
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self.error_handlers = {}
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#: A dictionary with lists of functions that should be called at the
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#: beginning of the request. The key of the dictionary is the name of
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#: the module this function is active for, `None` for all requests.
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#: This can for example be used to open database connections or
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#: getting hold of the currently logged in user. To register a
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#: function here, use the :meth:`before_request` decorator.
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self.before_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 module
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#: this function is active for, `None` for all requests. This can for
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#: example be used to open database connections or getting hold of the
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#: currently logged in user. To register a function here, use the
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#: :meth:`after_request` decorator.
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self.after_request_funcs = {}
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#: A dictionary with list of functions that are called without argument
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#: to populate the template context. The key of the dictionary is the
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#: name of the module this function is active for, `None` for all
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#: requests. Each returns a dictionary that the template context is
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#: updated with. To register a function here, use the
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#: :meth:`context_processor` decorator.
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self.template_context_processors = {
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None: [_default_template_ctx_processor]
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}
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#: all the loaded modules in a dictionary by name.
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#:
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#: .. versionadded:: 0.5
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self.modules = {}
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#: a place where extensions can store application specific state. For
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#: example this is where an extension could store database engines and
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#: similar things. For backwards compatibility extensions should register
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#: themselves like this::
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#:
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#: if not hasattr(app, 'extensions'):
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#: app.extensions = {}
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#: app.extensions['extensionname'] = SomeObject()
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#:
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#: The key must match the name of the `flaskext` module. For example in
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#: case of a "Flask-Foo" extension in `flaskext.foo`, the key would be
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#: ``'foo'``.
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#:
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#: .. versionadded:: 0.7
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self.extensions = {}
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#: The :class:`~werkzeug.routing.Map` for this instance. You can use
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#: this to change the routing converters after the class was created
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#: but before any routes are connected. Example::
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#:
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#: from werkzeug.routing import BaseConverter
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#:
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#: class ListConverter(BaseConverter):
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#: def to_python(self, value):
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#: return value.split(',')
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#: def to_url(self, values):
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#: return ','.join(BaseConverter.to_url(value)
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#: for value in values)
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#:
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#: app = Flask(__name__)
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#: app.url_map.converters['list'] = ListConverter
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self.url_map = Map()
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# register the static folder for the application. Do that even
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# if the folder does not exist. First of all it might be created
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# while the server is running (usually happens during development)
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# but also because google appengine stores static files somewhere
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# else when mapped with the .yml file.
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self.add_url_rule(self.static_path + '/<path:filename>',
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endpoint='static',
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view_func=self.send_static_file)
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#: The Jinja2 environment. It is created from the
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#: :attr:`jinja_options`.
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self.jinja_env = self.create_jinja_environment()
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self.init_jinja_globals()
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@property
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def propagate_exceptions(self):
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"""Returns the value of the `PROPAGATE_EXCEPTIONS` configuration
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value in case it's set, otherwise a sensible default is returned.
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.. versionadded:: 0.7
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"""
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rv = self.config['PROPAGATE_EXCEPTIONS']
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if rv is not None:
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return rv
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return self.testing or self.debug
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@property
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def logger(self):
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"""A :class:`logging.Logger` object for this application. The
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default configuration is to log to stderr if the application is
|
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in debug mode. This logger can be used to (surprise) log messages.
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Here some examples::
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app.logger.debug('A value for debugging')
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app.logger.warning('A warning ocurred (%d apples)', 42)
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app.logger.error('An error occoured')
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.. versionadded:: 0.3
|
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"""
|
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if self._logger and self._logger.name == self.logger_name:
|
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return self._logger
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with _logger_lock:
|
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if self._logger and self._logger.name == self.logger_name:
|
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return self._logger
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from flask.logging import create_logger
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self._logger = rv = create_logger(self)
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return rv
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|
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def create_jinja_environment(self):
|
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"""Creates the Jinja2 environment based on :attr:`jinja_options`
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and :meth:`select_jinja_autoescape`.
|
||||
|
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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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return Environment(loader=_DispatchingJinjaLoader(self), **options)
|
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|
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def init_jinja_globals(self):
|
||||
"""Called directly after the environment was created to inject
|
||||
some defaults (like `url_for`, `get_flashed_messages` and the
|
||||
`tojson` filter.
|
||||
|
||||
.. versionadded:: 0.5
|
||||
"""
|
||||
self.jinja_env.globals.update(
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url_for=url_for,
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||||
get_flashed_messages=get_flashed_messages
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||||
)
|
||||
self.jinja_env.filters['tojson'] = _tojson_filter
|
||||
|
||||
def select_jinja_autoescape(self, filename):
|
||||
"""Returns `True` if autoescaping should be active for the given
|
||||
template name.
|
||||
|
||||
.. versionadded:: 0.5
|
||||
"""
|
||||
if filename is None:
|
||||
return False
|
||||
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 overriden 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]
|
||||
mod = _request_ctx_stack.top.request.module
|
||||
if mod is not None and mod in self.template_context_processors:
|
||||
funcs = chain(funcs, self.template_context_processors[mod])
|
||||
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 run(self, host='127.0.0.1', port=5000, **options):
|
||||
"""Runs the application on a local development server. 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.
|
||||
|
||||
.. 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.
|
||||
:param port: the port of the webserver
|
||||
:param options: the options to be forwarded to the underlying
|
||||
Werkzeug server. See :func:`werkzeug.run_simple`
|
||||
for more information.
|
||||
"""
|
||||
from werkzeug import run_simple
|
||||
if 'debug' in options:
|
||||
self.debug = options.pop('debug')
|
||||
options.setdefault('use_reloader', self.debug)
|
||||
options.setdefault('use_debugger', self.debug)
|
||||
return run_simple(host, port, self, **options)
|
||||
|
||||
def test_client(self, use_cookies=True):
|
||||
"""Creates a test client for this application. For information
|
||||
about unit testing head over to :ref:`testing`.
|
||||
|
||||
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'
|
||||
|
||||
.. 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.
|
||||
"""
|
||||
cls = self.test_client_class
|
||||
if cls is None:
|
||||
from flask.testing import FlaskClient as cls
|
||||
return cls(self, self.response_class, use_cookies=use_cookies)
|
||||
|
||||
def open_session(self, request):
|
||||
"""Creates or opens a new session. Default implementation stores all
|
||||
session data in a signed cookie. This requires that the
|
||||
:attr:`secret_key` is set.
|
||||
|
||||
:param request: an instance of :attr:`request_class`.
|
||||
"""
|
||||
key = self.secret_key
|
||||
if key is not None:
|
||||
return Session.load_cookie(request, self.session_cookie_name,
|
||||
secret_key=key)
|
||||
|
||||
def save_session(self, session, response):
|
||||
"""Saves the session if it needs updates. For the default
|
||||
implementation, check :meth:`open_session`.
|
||||
|
||||
:param session: the session to be saved (a
|
||||
:class:`~werkzeug.contrib.securecookie.SecureCookie`
|
||||
object)
|
||||
:param response: an instance of :attr:`response_class`
|
||||
"""
|
||||
expires = domain = None
|
||||
if session.permanent:
|
||||
expires = datetime.utcnow() + self.permanent_session_lifetime
|
||||
if self.config['SERVER_NAME'] is not None:
|
||||
domain = '.' + self.config['SERVER_NAME']
|
||||
session.save_cookie(response, self.session_cookie_name,
|
||||
expires=expires, httponly=True, domain=domain)
|
||||
|
||||
def register_module(self, module, **options):
|
||||
"""Registers a module with this application. The keyword argument
|
||||
of this function are the same as the ones for the constructor of the
|
||||
:class:`Module` class and will override the values of the module if
|
||||
provided.
|
||||
"""
|
||||
options.setdefault('url_prefix', module.url_prefix)
|
||||
options.setdefault('subdomain', module.subdomain)
|
||||
self.view_functions.update(module.view_functions)
|
||||
state = _ModuleSetupState(self, **options)
|
||||
for func in module._register_events:
|
||||
func(state)
|
||||
|
||||
def add_url_rule(self, rule, endpoint=None, view_func=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)
|
||||
|
||||
If the view_func is not provided you will need to connect the endpoint
|
||||
to a view function like so::
|
||||
|
||||
app.view_functions['index'] = index
|
||||
|
||||
.. versionchanged:: 0.2
|
||||
`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 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', ('GET',))
|
||||
provide_automatic_options = False
|
||||
if 'OPTIONS' not in methods:
|
||||
methods = tuple(methods) + ('OPTIONS',)
|
||||
provide_automatic_options = True
|
||||
rule = Rule(rule, methods=methods, **options)
|
||||
rule.provide_automatic_options = provide_automatic_options
|
||||
self.url_map.add(rule)
|
||||
if view_func is not None:
|
||||
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. Example::
|
||||
|
||||
@app.route('/')
|
||||
def index():
|
||||
return 'Hello World'
|
||||
|
||||
Variables parts in the route can be specified with angular
|
||||
brackets (``/user/<username>``). By default a variable part
|
||||
in the URL accepts any string without a slash however a different
|
||||
converter can be specified as well by using ``<converter:name>``.
|
||||
|
||||
Variable parts are passed to the view function as keyword
|
||||
arguments.
|
||||
|
||||
The following converters are possible:
|
||||
|
||||
=========== ===========================================
|
||||
`int` accepts integers
|
||||
`float` like `int` but for floating point values
|
||||
`path` like the default but also accepts slashes
|
||||
=========== ===========================================
|
||||
|
||||
Here some examples::
|
||||
|
||||
@app.route('/')
|
||||
def index():
|
||||
pass
|
||||
|
||||
@app.route('/<username>')
|
||||
def show_user(username):
|
||||
pass
|
||||
|
||||
@app.route('/post/<int:post_id>')
|
||||
def show_post(post_id):
|
||||
pass
|
||||
|
||||
An important detail to keep in mind is how Flask deals with trailing
|
||||
slashes. The idea is to keep each URL unique so the following rules
|
||||
apply:
|
||||
|
||||
1. If a rule ends with a slash and is requested without a slash
|
||||
by the user, the user is automatically redirected to the same
|
||||
page with a trailing slash attached.
|
||||
2. If a rule does not end with a trailing slash and the user request
|
||||
the page with a trailing slash, a 404 not found is raised.
|
||||
|
||||
This is consistent with how web servers deal with static files. This
|
||||
also makes it possible to use relative link targets safely.
|
||||
|
||||
The :meth:`route` decorator accepts a couple of other arguments
|
||||
as well:
|
||||
|
||||
:param rule: the URL rule as string
|
||||
:param methods: 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.
|
||||
:param subdomain: specifies the rule for the subdomain in case
|
||||
subdomain matching is in use.
|
||||
:param strict_slashes: can be used to disable the strict slashes
|
||||
setting for this rule. See above.
|
||||
:param options: other options to be forwarded to the underlying
|
||||
:class:`~werkzeug.routing.Rule` object.
|
||||
"""
|
||||
def decorator(f):
|
||||
self.add_url_rule(rule, None, f, **options)
|
||||
return f
|
||||
return decorator
|
||||
|
||||
|
||||
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
|
||||
|
||||
def errorhandler(self, code):
|
||||
"""A decorator that is used to register a function give a given
|
||||
error code. Example::
|
||||
|
||||
@app.errorhandler(404)
|
||||
def page_not_found(error):
|
||||
return 'This page does not exist', 404
|
||||
|
||||
You can also register a function as error handler without using
|
||||
the :meth:`errorhandler` decorator. The following example is
|
||||
equivalent to the one above::
|
||||
|
||||
def page_not_found(error):
|
||||
return 'This page does not exist', 404
|
||||
app.error_handlers[404] = page_not_found
|
||||
|
||||
:param code: the code as integer for the handler
|
||||
"""
|
||||
def decorator(f):
|
||||
self.error_handlers[code] = f
|
||||
return f
|
||||
return decorator
|
||||
|
||||
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.jinja_env.filters[name or f.__name__] = f
|
||||
return f
|
||||
return decorator
|
||||
|
||||
def before_request(self, f):
|
||||
"""Registers a function to run before each request."""
|
||||
self.before_request_funcs.setdefault(None, []).append(f)
|
||||
return f
|
||||
|
||||
def after_request(self, f):
|
||||
"""Register a function to be run after each request."""
|
||||
self.after_request_funcs.setdefault(None, []).append(f)
|
||||
return f
|
||||
|
||||
def context_processor(self, f):
|
||||
"""Registers a template context processor function."""
|
||||
self.template_context_processors[None].append(f)
|
||||
return f
|
||||
|
||||
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.
|
||||
|
||||
.. versionadded: 0.3
|
||||
"""
|
||||
handler = self.error_handlers.get(e.code)
|
||||
if handler is None:
|
||||
return e
|
||||
return handler(e)
|
||||
|
||||
def handle_exception(self, e):
|
||||
"""Default exception handling that kicks in when an exception
|
||||
occours that is not catched. 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
|
||||
"""
|
||||
got_request_exception.send(self, exception=e)
|
||||
handler = self.error_handlers.get(500)
|
||||
if self.propagate_exceptions:
|
||||
raise
|
||||
self.logger.exception('Exception on %s [%s]' % (
|
||||
request.path,
|
||||
request.method
|
||||
))
|
||||
if handler is None:
|
||||
return InternalServerError()
|
||||
return handler(e)
|
||||
|
||||
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`.
|
||||
"""
|
||||
req = _request_ctx_stack.top.request
|
||||
try:
|
||||
if req.routing_exception is not None:
|
||||
raise req.routing_exception
|
||||
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)
|
||||
except HTTPException, e:
|
||||
return self.handle_http_exception(e)
|
||||
|
||||
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
|
||||
behaviour of `OPTIONS` responses.
|
||||
|
||||
.. versionadded:: 0.7
|
||||
"""
|
||||
# This would be nicer in Werkzeug 0.7, which however currently
|
||||
# is not released. Werkzeug 0.7 provides a method called
|
||||
# allowed_methods() that returns all methods that are valid for
|
||||
# a given path.
|
||||
methods = []
|
||||
try:
|
||||
_request_ctx_stack.top.url_adapter.match(method='--')
|
||||
except MethodNotAllowed, e:
|
||||
methods = e.valid_methods
|
||||
except HTTPException, e:
|
||||
pass
|
||||
rv = self.response_class()
|
||||
rv.allow.update(methods)
|
||||
return rv
|
||||
|
||||
def make_response(self, rv):
|
||||
"""Converts the return value from a view function to a real
|
||||
response object that is an instance of :attr:`response_class`.
|
||||
|
||||
The following types are allowed for `rv`:
|
||||
|
||||
.. tabularcolumns:: |p{3.5cm}|p{9.5cm}|
|
||||
|
||||
======================= ===========================================
|
||||
:attr:`response_class` the object is returned unchanged
|
||||
:class:`str` a response object is created with the
|
||||
string as body
|
||||
:class:`unicode` a response object is created with the
|
||||
string encoded to utf-8 as body
|
||||
:class:`tuple` the response object is created with the
|
||||
contents of the tuple as arguments
|
||||
a WSGI function the function is called as WSGI application
|
||||
and buffered as response object
|
||||
======================= ===========================================
|
||||
|
||||
:param rv: the return value from the view function
|
||||
"""
|
||||
if rv is None:
|
||||
raise ValueError('View function did not return a response')
|
||||
if isinstance(rv, self.response_class):
|
||||
return rv
|
||||
if isinstance(rv, basestring):
|
||||
return self.response_class(rv)
|
||||
if isinstance(rv, tuple):
|
||||
return self.response_class(*rv)
|
||||
return self.response_class.force_type(rv, request.environ)
|
||||
|
||||
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
|
||||
"""
|
||||
return self.url_map.bind_to_environ(request.environ,
|
||||
server_name=self.config['SERVER_NAME'])
|
||||
|
||||
def preprocess_request(self):
|
||||
"""Called before the actual request dispatching and will
|
||||
call every as :meth:`before_request` decorated function.
|
||||
If any of these function returns a value it's handled as
|
||||
if it was the return value from the view and further
|
||||
request handling is stopped.
|
||||
"""
|
||||
funcs = self.before_request_funcs.get(None, ())
|
||||
mod = request.module
|
||||
if mod and mod in self.before_request_funcs:
|
||||
funcs = chain(funcs, self.before_request_funcs[mod])
|
||||
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
|
||||
mod = ctx.request.module
|
||||
if not isinstance(ctx.session, _NullSession):
|
||||
self.save_session(ctx.session, response)
|
||||
funcs = ()
|
||||
if mod and mod in self.after_request_funcs:
|
||||
funcs = reversed(self.after_request_funcs[mod])
|
||||
if None in self.after_request_funcs:
|
||||
funcs = chain(funcs, reversed(self.after_request_funcs[None]))
|
||||
for handler in funcs:
|
||||
response = handler(response)
|
||||
return response
|
||||
|
||||
def request_context(self, environ):
|
||||
"""Creates a request context from the given environment and binds
|
||||
it to the current context. This must be used in combination with
|
||||
the `with` statement because the request is only bound to the
|
||||
current context for the duration of the `with` block.
|
||||
|
||||
Example usage::
|
||||
|
||||
with app.request_context(environ):
|
||||
do_something_with(request)
|
||||
|
||||
The object returned can also be used without the `with` statement
|
||||
which is useful for working in the shell. The example above is
|
||||
doing exactly the same as this code::
|
||||
|
||||
ctx = app.request_context(environ)
|
||||
ctx.push()
|
||||
try:
|
||||
do_something_with(request)
|
||||
finally:
|
||||
ctx.pop()
|
||||
|
||||
The big advantage of this approach is that you can use it without
|
||||
the try/finally statement in a shell for interactive testing:
|
||||
|
||||
>>> ctx = app.test_request_context()
|
||||
>>> ctx.bind()
|
||||
>>> request.path
|
||||
u'/'
|
||||
>>> ctx.unbind()
|
||||
|
||||
.. versionchanged:: 0.3
|
||||
Added support for non-with statement usage and `with` statement
|
||||
is now passed the ctx object.
|
||||
|
||||
:param environ: a WSGI environment
|
||||
"""
|
||||
return _RequestContext(self, environ)
|
||||
|
||||
def test_request_context(self, *args, **kwargs):
|
||||
"""Creates a WSGI environment from the given values (see
|
||||
:func:`werkzeug.create_environ` for more information, this
|
||||
function accepts the same arguments).
|
||||
"""
|
||||
from werkzeug import create_environ
|
||||
environ_overrides = kwargs.setdefault('environ_overrides', {})
|
||||
if self.config.get('SERVER_NAME'):
|
||||
server_name = self.config.get('SERVER_NAME')
|
||||
if ':' not in server_name:
|
||||
http_host, http_port = server_name, '80'
|
||||
else:
|
||||
http_host, http_port = server_name.split(':', 1)
|
||||
|
||||
environ_overrides.setdefault('SERVER_NAME', server_name)
|
||||
environ_overrides.setdefault('HTTP_HOST', server_name)
|
||||
environ_overrides.setdefault('SERVER_PORT', http_port)
|
||||
return self.request_context(create_environ(*args, **kwargs))
|
||||
|
||||
def wsgi_app(self, environ, start_response):
|
||||
"""The actual WSGI application. This is not implemented in
|
||||
`__call__` so that middlewares can be applied without losing a
|
||||
reference to the class. So 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:: 0.4
|
||||
The :meth:`after_request` functions are now called even if an
|
||||
error handler took over request processing. This ensures that
|
||||
even if an exception happens database have the chance to
|
||||
properly close the connection.
|
||||
|
||||
: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
|
||||
"""
|
||||
with self.request_context(environ):
|
||||
try:
|
||||
request_started.send(self)
|
||||
rv = self.preprocess_request()
|
||||
if rv is None:
|
||||
rv = self.dispatch_request()
|
||||
response = self.make_response(rv)
|
||||
except Exception, e:
|
||||
response = self.make_response(self.handle_exception(e))
|
||||
try:
|
||||
response = self.process_response(response)
|
||||
except Exception, e:
|
||||
response = self.make_response(self.handle_exception(e))
|
||||
request_finished.send(self, response=response)
|
||||
return response(environ, start_response)
|
||||
|
||||
def __call__(self, environ, start_response):
|
||||
"""Shortcut for :attr:`wsgi_app`."""
|
||||
return self.wsgi_app(environ, start_response)
|
||||
Reference in New Issue
Block a user