Can't parse a 1904 date in ARPA format (email date)

Question

I'm processing an IMAP mailbox and running into trouble parsing the dates using the mxDateTime package. In particular, early dates like "Fri, 1 Jan 1904 00:43:25 -0400" is causing trouble:

>>> import mx.DateTime
>>> import mx.DateTime.ARPA
>>> mx.DateTime.ARPA.ParseDateTimeUTC("Fri, 1 Jan 1904 00:43:25 -0400").gmtoffset()
Traceback (most recent call last):
  File "<interactive input>", line 1, in <module>
Error: cannot convert value to a time value
>>> mx.DateTime.ARPA.ParseDateTimeUTC("Thu, 1 Jan 2009 00:43:25 -0400").gmtoffset()
<mx.DateTime.DateTimeDelta object for '-08:00:00.00' at 1497b60>
>>> 

Note that an almost identical date from 2009 works fine. I can't find any description of date limitations in mxDateTime itself. Any ideas why this might be?

Thx,

Ramon

Answer 1

Is it possible that the mxDateTime object only handles datetimes which fall after the Unix Epoch?

Answer 2

Figured it out with the help of the eGenix folks. It is an Epoch problem, but you can work around it by manually extracting the timezone offset and then re-applying explicitly:

>>> s = "Wed, 1 Jan 1969 00:43:25 -0400"
>>> delta = ParseDateTime(s) - ParseDateTimeUTC(s)
Traceback (most recent call last):
 File "<interactive input>", line 1, in <module>
 NameError: name 'ParseDateTime' is not defined
>>> delta = mx.DateTime.ARPA.ParseDateTime(s) - mx.DateTime.ARPA.ParseDateTimeUTC(s)
>>> mx.DateTime.ARPA.str(mx.DateTime.ARPA.ParseDateTime(s), delta)
'Wed, 01 Jan 1969 00:43:25 -0400'
>>>

Thanks everyone!