name : email.errors.rst.txt :mod:`email.errors`: Exception and Defect classes ------------------------------------------------- .. module:: email.errors :synopsis: The exception classes used by the email package. **Source code:** :source:`Lib/email/errors.py` -------------- The following exception classes are defined in the :mod:`email.errors` module: .. exception:: MessageError() This is the base class for all exceptions that the :mod:`email` package can raise. It is derived from the standard :exc:`Exception` class and defines no additional methods. .. exception:: MessageParseError() This is the base class for exceptions raised by the :class:`~email.parser.Parser` class. It is derived from :exc:`MessageError`. This class is also used internally by the parser used by :mod:`~email.headerregistry`. .. exception:: HeaderParseError() Raised under some error conditions when parsing the :rfc:`5322` headers of a message, this class is derived from :exc:`MessageParseError`. The :meth:`~email.message.EmailMessage.set_boundary` method will raise this error if the content type is unknown when the method is called. :class:`~email.header.Header` may raise this error for certain base64 decoding errors, and when an attempt is made to create a header that appears to contain an embedded header (that is, there is what is supposed to be a continuation line that has no leading whitespace and looks like a header). .. exception:: BoundaryError() Deprecated and no longer used. .. exception:: MultipartConversionError() Raised when a payload is added to a :class:`~email.message.Message` object using :meth:`add_payload`, but the payload is already a scalar and the message's :mailheader:`Content-Type` main type is not either :mimetype:`multipart` or missing. :exc:`MultipartConversionError` multiply inherits from :exc:`MessageError` and the built-in :exc:`TypeError`. Since :meth:`Message.add_payload` is deprecated, this exception is rarely raised in practice. However the exception may also be raised if the :meth:`~email.message.Message.attach` method is called on an instance of a class derived from :class:`~email.mime.nonmultipart.MIMENonMultipart` (e.g. :class:`~email.mime.image.MIMEImage`). Here is the list of the defects that the :class:`~email.parser.FeedParser` can find while parsing messages. Note that the defects are added to the message where the problem was found, so for example, if a message nested inside a :mimetype:`multipart/alternative` had a malformed header, that nested message object would have a defect, but the containing messages would not. All defect classes are subclassed from :class:`email.errors.MessageDefect`. * :class:`NoBoundaryInMultipartDefect` -- A message claimed to be a multipart, but had no :mimetype:`boundary` parameter. * :class:`StartBoundaryNotFoundDefect` -- The start boundary claimed in the :mailheader:`Content-Type` header was never found. * :class:`CloseBoundaryNotFoundDefect` -- A start boundary was found, but no corresponding close boundary was ever found. .. versionadded:: 3.3 * :class:`FirstHeaderLineIsContinuationDefect` -- The message had a continuation line as its first header line. * :class:`MisplacedEnvelopeHeaderDefect` - A "Unix From" header was found in the middle of a header block. * :class:`MissingHeaderBodySeparatorDefect` - A line was found while parsing headers that had no leading white space but contained no ':'. Parsing continues assuming that the line represents the first line of the body. .. versionadded:: 3.3 * :class:`MalformedHeaderDefect` -- A header was found that was missing a colon, or was otherwise malformed. .. deprecated:: 3.3 This defect has not been used for several Python versions. * :class:`MultipartInvariantViolationDefect` -- A message claimed to be a :mimetype:`multipart`, but no subparts were found. Note that when a message has this defect, its :meth:`~email.message.Message.is_multipart` method may return false even though its content type claims to be :mimetype:`multipart`. * :class:`InvalidBase64PaddingDefect` -- When decoding a block of base64 encoded bytes, the padding was not correct. Enough padding is added to perform the decode, but the resulting decoded bytes may be invalid. * :class:`InvalidBase64CharactersDefect` -- When decoding a block of base64 encoded bytes, characters outside the base64 alphabet were encountered. The characters are ignored, but the resulting decoded bytes may be invalid. * :class:`InvalidBase64LengthDefect` -- When decoding a block of base64 encoded bytes, the number of non-padding base64 characters was invalid (1 more than a multiple of 4). The encoded block was kept as-is.