18.1.8. email.errors: Exception and Defect classes
The following exception classes are defined in the email.errors module:
-
exception
email.errors.MessageError
This is the base class for all exceptions that the email package can
raise. It is derived from the standard Exception class and defines no
additional methods.
-
exception
email.errors.MessageParseError
This is the base class for exceptions raised by the Parser
class. It is derived from MessageError.
Raised under some error conditions when parsing the RFC 2822 headers of a
message, this class is derived from MessageParseError. It can be raised
from the Parser.parse or
Parser.parsestr methods.
Situations where it can be raised include finding an envelope header after the
first RFC 2822 header of the message, finding a continuation line before the
first RFC 2822 header is found, or finding a line in the headers which is
neither a header or a continuation line.
-
exception
email.errors.BoundaryError
Raised under some error conditions when parsing the RFC 2822 headers of a
message, this class is derived from MessageParseError. It can be raised
from the Parser.parse or
Parser.parsestr methods.
Situations where it can be raised include not being able to find the starting or
terminating boundary in a multipart/* message when strict parsing
is used.
-
exception
email.errors.MultipartConversionError
Raised when a payload is added to a Message object
using add_payload(), but the payload is already a scalar and the
message’s main type is not either
multipart or missing. MultipartConversionError multiply
inherits from MessageError and the built-in TypeError.
Since Message.add_payload() is deprecated, this exception is rarely
raised in practice. However the exception may also be raised if the
attach()
method is called on an instance of a class derived from
MIMENonMultipart (e.g.
MIMEImage).
Here’s the list of the defects that the 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
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 email.errors.MessageDefect, but
this class is not an exception!
New in version 2.4: All the defect classes were added.
NoBoundaryInMultipartDefect – A message claimed to be a multipart,
but had no boundary parameter.
StartBoundaryNotFoundDefect – The start boundary claimed in the
header was never found.
FirstHeaderLineIsContinuationDefect – The message had a continuation
line as its first header line.
MisplacedEnvelopeHeaderDefect - A “Unix From” header was found in the
middle of a header block.
MalformedHeaderDefect – A header was found that was missing a colon,
or was otherwise malformed.
MultipartInvariantViolationDefect – A message claimed to be a
multipart, but no subparts were found. Note that when a message
has this defect, its is_multipart() method may
return false even though its content type claims to be multipart.