imaplib ... understanding the result from a fetch of RFC822s

[Donn Cave]

In article <419bb3a7$0$259$edfadb0f at dread12.news.tele.dk>,
 Max M <maxm at mxm.dk> wrote:
> I am using the fetch command from the imaplib to fetch messages. I get a 
> result, but I am a bit uncertain as to how I should interpret it.
> 
> The result is described at http://pydoc.org/2.3/imaplib.html as::
> 
> (typ, [data, ...]) = <instance>.fetch(message_set, message_parts)
> 
> In RFC 2060 it says: "The data items to be fetched can be either a 
> single atom or a parenthesized list."
> 
> So I do a fetch like:
> 
>      mailconn.uid('fetch', '1:*', '(RFC822)')
> 
> As a result I receive the following results (from 2 different servers):
> 
> # mailserver 1
> messages = [
>      ('1 (UID 2 RFC822 {616}', "Received: from SNIP..."),
>      ')',
>      ('2 (UID 4 RFC822 {626}', "Received: from SNIP..."),
>      ')',
> ]
...
> Does anybody have a clue as to why imaplib returns results like that?

It has to parse the response that far, in order to read the
whole thing.  That '{616}' is as you probably surmised the
length of the following text, spanning more than a single line,
so imaplib needs that number.  The intent is not to provide
you with a fully parsed IMAP4 response, you're just getting
the data and whatever parsing was needed along the way.  In
a perversely ideal sense, it might have been better to put
the pieces back together and just give you the response as
one string.

   Donn Cave, donn at u.washington.edu