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Fonction url_for - module flask

Signature de la fonction url_for

def url_for(endpoint: str, **values: Any) -> str 

Description

url_for.__doc__

Generates a URL to the given endpoint with the method provided.

    Variable arguments that are unknown to the target endpoint are appended
    to the generated URL as query arguments.  If the value of a query argument
    is ``None``, the whole pair is skipped.  In case blueprints are active
    you can shortcut references to the same blueprint by prefixing the
    local endpoint with a dot (``.``).

    This will reference the index function local to the current blueprint::

        url_for('.index')

    See :ref:`url-building`.

    Configuration values ``APPLICATION_ROOT`` and ``SERVER_NAME`` are only used when
    generating URLs outside of a request context.

    To integrate applications, :class:`Flask` has a hook to intercept URL build
    errors through :attr:`Flask.url_build_error_handlers`.  The `url_for`
    function results in a :exc:`~werkzeug.routing.BuildError` when the current
    app does not have a URL for the given endpoint and values.  When it does, the
    :data:`~flask.current_app` calls its :attr:`~Flask.url_build_error_handlers` if
    it is not ``None``, which can return a string to use as the result of
    `url_for` (instead of `url_for`'s default to raise the
    :exc:`~werkzeug.routing.BuildError` exception) or re-raise the exception.
    An example::

        def external_url_handler(error, endpoint, values):
            "Looks up an external URL when `url_for` cannot build a URL."
            # This is an example of hooking the build_error_handler.
            # Here, lookup_url is some utility function you've built
            # which looks up the endpoint in some external URL registry.
            url = lookup_url(endpoint, **values)
            if url is None:
                # External lookup did not have a URL.
                # Re-raise the BuildError, in context of original traceback.
                exc_type, exc_value, tb = sys.exc_info()
                if exc_value is error:
                    raise exc_type(exc_value).with_traceback(tb)
                else:
                    raise error
            # url_for will use this result, instead of raising BuildError.
            return url

        app.url_build_error_handlers.append(external_url_handler)

    Here, `error` is the instance of :exc:`~werkzeug.routing.BuildError`, and
    `endpoint` and `values` are the arguments passed into `url_for`.  Note
    that this is for building URLs outside the current application, and not for
    handling 404 NotFound errors.

    .. versionadded:: 0.10
       The `_scheme` parameter was added.

    .. versionadded:: 0.9
       The `_anchor` and `_method` parameters were added.

    .. versionadded:: 0.9
       Calls :meth:`Flask.handle_build_error` on
       :exc:`~werkzeug.routing.BuildError`.

    :param endpoint: the endpoint of the URL (name of the function)
    :param values: the variable arguments of the URL rule
    :param _external: if set to ``True``, an absolute URL is generated. Server
      address can be changed via ``SERVER_NAME`` configuration variable which
      falls back to the `Host` header, then to the IP and port of the request.
    :param _scheme: a string specifying the desired URL scheme. The `_external`
      parameter must be set to ``True`` or a :exc:`ValueError` is raised. The default
      behavior uses the same scheme as the current request, or
      :data:`PREFERRED_URL_SCHEME` if no request context is available.
      This also can be set to an empty string to build protocol-relative
      URLs.
    :param _anchor: if provided this is added as anchor to the URL.
    :param _method: if provided this explicitly specifies an HTTP method.