mitmproxy/mitmproxy/exceptions.py

"""
We try to be very hygienic regarding the exceptions we throw:
Every Exception mitmproxy raises shall be a subclass of ProxyException.


See also: http://lucumr.pocoo.org/2014/10/16/on-error-handling/
"""
from __future__ import (absolute_import, print_function, division)

import traceback

import sys


class ProxyException(Exception):

    """
    Base class for all exceptions thrown by mitmproxy.
    """

    def __init__(self, message=None):
        super(ProxyException, self).__init__(message)


class Kill(ProxyException):

    """
    Signal that both client and server connection(s) should be killed immediately.
    """
    pass


class ProtocolException(ProxyException):
    pass


class TlsProtocolException(ProtocolException):
    pass


class ClientHandshakeException(TlsProtocolException):

    def __init__(self, message, server):
        super(ClientHandshakeException, self).__init__(message)
        self.server = server


class Socks5ProtocolException(ProtocolException):
    pass


class HttpProtocolException(ProtocolException):
    pass


class Http2ProtocolException(ProtocolException):
    pass


class ServerException(ProxyException):
    pass


class ContentViewException(ProxyException):
    pass


class ReplayException(ProxyException):
    pass


class ScriptException(ProxyException):

    @classmethod
    def from_exception_context(cls, cut_tb=1):
        """
        Must be called while the current stack handles an exception.

        Args:
            cut_tb: remove N frames from the stack trace to hide internal calls.
        """
        exc_type, exc_value, exc_traceback = sys.exc_info()

        while cut_tb > 0:
            exc_traceback = exc_traceback.tb_next
            cut_tb -= 1

        tb = "".join(traceback.format_exception(exc_type, exc_value, exc_traceback))

        return cls(tb)


class FlowReadException(ProxyException):
    pass


class ControlException(Exception):
    pass