debughelpers.py — flask Source File

Source Code

from __future__ import annotations

import typing as t

from jinja2.loaders import BaseLoader
from werkzeug.routing import RequestRedirect

from .blueprints import Blueprint
from .globals import _cv_app
from .sansio.app import App

if t.TYPE_CHECKING:
    from .sansio.scaffold import Scaffold
    from .wrappers import Request


class UnexpectedUnicodeError(AssertionError, UnicodeError):
    """Raised in places where we want some better error reporting for
    unexpected unicode or binary data.
    """


class DebugFilesKeyError(KeyError, AssertionError):
    """Raised from request.files during debugging.  The idea is that it can
    provide a better error message than just a generic KeyError/BadRequest.
    """

    def __init__(self, request: Request, key: str) -> None:
        form_matches = request.form.getlist(key)
        buf = [
            f"You tried to access the file {key!r} in the request.files"
            " dictionary but it does not exist. The mimetype for the"
            f" request is {request.mimetype!r} instead of"
            " 'multipart/form-data' which means that no file contents"
            " were transmitted. To fix this error you should provide"
            ' enctype="multipart/form-data" in your form.'
        ]
        if form_matches:
            names = ", ".join(repr(x) for x in form_matches)
            buf.append(
                "\n\nThe browser instead transmitted some file names. "
                f"This was submitted: {names}"
            )
        self.msg = "".join(buf)

    def __str__(self) -> str:
        return self.msg


class FormDataRoutingRedirect(AssertionError):
    """This exception is raised in debug mode if a routing redirect
    would cause the browser to drop the method or body. This happens
    when method is not GET, HEAD or OPTIONS and the status code is not
    307 or 308.
    """

    def __init__(self, request: Request) -> None:
        exc = request.routing_exception
        assert isinstance(exc, RequestRedirect)
        buf = [
// ... (120 more lines)