Synnefo » ./kamaki

# Copyright 2012 GRNET S.A. All rights reserved.

#

# Redistribution and use in source and binary forms, with or

# without modification, are permitted provided that the following

# conditions are met:

#

#   1. Redistributions of source code must retain the above

#      copyright notice, this list of conditions and the following

#      disclaimer.

#

#   2. Redistributions in binary form must reproduce the above

#      copyright notice, this list of conditions and the following

#      disclaimer in the documentation and/or other materials

#      provided with the distribution.

#

# THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS

# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR

# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF

# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED

# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN

# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

# POSSIBILITY OF SUCH DAMAGE.

#

# The views and conclusions contained in the software and

# documentation are those of the authors and should not be

# interpreted as representing official policies, either expressed

# or implied, of GRNET S.A.

def str_or_utf8(s):

    if isinstance(s, unicode):

        return s.encode('utf8')

    return str(s)

class CallError(Exception):

    exceptions = {}

    def __new__(cls, *args, **kw):

        call_error = kw.get('call_error', None)

        if call_error is None:

            call_error = cls.__name__

        else:

            call_error = str(call_error)

        cls = CallError.exceptions.get(call_error, cls)

        self = Exception.__new__(cls)

        return self

    def __init__(self, *args, **kw):

        self.call_error = kw.pop('call_error', self.__class__.__name__)

        self.args = args

        self.kwargs = kw

    def __str__(self):

        return '\n--------\n'.join(str_or_utf8(x) for x in self.args)

    def __repr__(self):

        return '%s(%s)' % (self.__class__.__name__,

                           ','.join(str_or_utf8(x) for x in self.args))

    @classmethod

    def from_exception(cls, exc):

        args = None

        try:

            args = tuple(exc.args)

        except (TypeError, AttributeError):

            pass

        if args is None:

            args = (str(exc),)

        self = cls(*args, call_error=exc.__class__.__name__)

        return self

    def to_dict(self):

        return {'call_error': self.call_error,

                'error_args': (self.args, self.kwargs)}

    @classmethod

    def from_dict(cls, dictobj):

        args = None

        try:

            if 'error_args' in dictobj and 'call_error' in dictobj:

                args = dictobj['error_args']

                call_error = dictobj['call_error']

        except TypeError:

            pass

        if args is None:

            args = (str(dictobj),)

            call_error = 'UnknownError'

            kw = {}

        else:

            args, kw = args

        self = cls(*args, call_error=call_error, **kw)

        return self

def register_exceptions(*exceptions):

    for exception in exceptions:

        if not issubclass(exception, CallError):

            m = "Registering '%s': is not a CallError subclass" % (exception,)

            raise ValueError(m)

        CallError.exceptions[exception.__name__] = exception

def register_exception(exc):

    register_exceptions(exc)

    return exc

@register_exception

class CorruptedError(CallError):

    pass

@register_exception

class InvalidDataError(CallError):

    pass

class ReturnButFail(Exception):

    def __init__(self, retval=None):

        self.data = retval