Add "Received:" header to email msg in correct position?

[Burak Arslan]

On 05/06/14 18:26, Grant Edwards wrote:
> On 2014-05-06, Burak Arslan <burak.arslan at arskom.com.tr> wrote:
>> On 05/06/14 12:47, Chris Angelico wrote:
>>> On Tue, May 6, 2014 at 7:15 PM, alister
>>> <alister.nospam.ware at ntlworld.com> wrote:
>>>> On Mon, 05 May 2014 19:51:15 +0000, Grant Edwards wrote:
>>>>
>>>>> I'm working on a Python app that receives an e-mail message via SMTP,
>>>>> does some trivial processing on it, and forwards it to another SMTP
>>>>> server.
>>>>>
>>>>> I'd like to do the polite thing and add a "Received:" header, but I
>>>>> can't figure out how to get Python's email module to add it in the
>>>>> correct place.  It always ends up at the "bottom" of the headers below
>>>>> From: To: etc.  It's supposed to go at the above all the Received:
>>>>> headers that where there when I received it.
>>>> Is this required or just being polite?
>>>> what I mean is does the standard state the headers must be in a
>>>> particular order or can they appear anywhere, you may be spending time
>>>> trying to resolve an issue that does not need fixing.
>>> Yes, it's required. RFC 2821 [1] section 3.8.2 says "prepend".
>> The rationale for "prepend" is to make it possible for MTAs to add
>> their "Received:" headers to messages without having to parse them.
>>
>> So you're supposed to do the same: Just write your Received header,
>> followed by '\r\n', followed by the rest of the message to the socket
>> and you should be fine.
> I need to check and manipulate other headers for other reasons, so I'm
> using the email module for that.  In order to keep things consistent
> and easy to understand, I'd like to use the email module to prepend
> the Received header as well.  That keeps my application from having to
> have any knowledge about e-mail message formatting.
>

Seeing how discussion is still going on about this, I'd like to state
once more what I said above in other words: You just need to do this:

"Received: blah\r\n" + message.to_string()

or better:

socket.write("Received: blah\r\n")
socket.write(message.to_string())

And again, this is not a hack, this is how it's supposed to work.

Burak