1:mod:`email.errors`: Exception and Defect classes 2------------------------------------------------- 3 4.. module:: email.errors 5 :synopsis: The exception classes used by the email package. 6 7 8The following exception classes are defined in the :mod:`email.errors` module: 9 10 11.. exception:: MessageError() 12 13 This is the base class for all exceptions that the :mod:`email` package can 14 raise. It is derived from the standard :exc:`Exception` class and defines no 15 additional methods. 16 17 18.. exception:: MessageParseError() 19 20 This is the base class for exceptions raised by the :class:`~email.parser.Parser` 21 class. It is derived from :exc:`MessageError`. 22 23 24.. exception:: HeaderParseError() 25 26 Raised under some error conditions when parsing the :rfc:`2822` headers of a 27 message, this class is derived from :exc:`MessageParseError`. It can be raised 28 from the :meth:`Parser.parse <email.parser.Parser.parse>` or 29 :meth:`Parser.parsestr <email.parser.Parser.parsestr>` methods. 30 31 Situations where it can be raised include finding an envelope header after the 32 first :rfc:`2822` header of the message, finding a continuation line before the 33 first :rfc:`2822` header is found, or finding a line in the headers which is 34 neither a header or a continuation line. 35 36 37.. exception:: BoundaryError() 38 39 Raised under some error conditions when parsing the :rfc:`2822` headers of a 40 message, this class is derived from :exc:`MessageParseError`. It can be raised 41 from the :meth:`Parser.parse <email.parser.Parser.parse>` or 42 :meth:`Parser.parsestr <email.parser.Parser.parsestr>` methods. 43 44 Situations where it can be raised include not being able to find the starting or 45 terminating boundary in a :mimetype:`multipart/\*` message when strict parsing 46 is used. 47 48 49.. exception:: MultipartConversionError() 50 51 Raised when a payload is added to a :class:`~email.message.Message` object 52 using :meth:`add_payload`, but the payload is already a scalar and the 53 message's :mailheader:`Content-Type` main type is not either 54 :mimetype:`multipart` or missing. :exc:`MultipartConversionError` multiply 55 inherits from :exc:`MessageError` and the built-in :exc:`TypeError`. 56 57 Since :meth:`Message.add_payload` is deprecated, this exception is rarely 58 raised in practice. However the exception may also be raised if the 59 :meth:`~email.message.Message.attach` 60 method is called on an instance of a class derived from 61 :class:`~email.mime.nonmultipart.MIMENonMultipart` (e.g. 62 :class:`~email.mime.image.MIMEImage`). 63 64Here's the list of the defects that the :class:`~email.parser.FeedParser` 65can find while parsing messages. Note that the defects are added to the message 66where the problem was found, so for example, if a message nested inside a 67:mimetype:`multipart/alternative` had a malformed header, that nested message 68object would have a defect, but the containing messages would not. 69 70All defect classes are subclassed from :class:`email.errors.MessageDefect`, but 71this class is *not* an exception! 72 73.. versionadded:: 2.4 74 All the defect classes were added. 75 76* :class:`NoBoundaryInMultipartDefect` -- A message claimed to be a multipart, 77 but had no :mimetype:`boundary` parameter. 78 79* :class:`StartBoundaryNotFoundDefect` -- The start boundary claimed in the 80 :mailheader:`Content-Type` header was never found. 81 82* :class:`FirstHeaderLineIsContinuationDefect` -- The message had a continuation 83 line as its first header line. 84 85* :class:`MisplacedEnvelopeHeaderDefect` - A "Unix From" header was found in the 86 middle of a header block. 87 88* :class:`MalformedHeaderDefect` -- A header was found that was missing a colon, 89 or was otherwise malformed. 90 91* :class:`MultipartInvariantViolationDefect` -- A message claimed to be a 92 :mimetype:`multipart`, but no subparts were found. Note that when a message 93 has this defect, its :meth:`~email.message.Message.is_multipart` method may 94 return false even though its content type claims to be :mimetype:`multipart`. 95 96