Convert Python datetime to rfc 2822

Question

I want to convert a Python datetime to an RFC 2822 datetime. I've tried these methods to no avail:

>>> from email.Utils import formatdate >>> import datetime >>> formatdate(datetime.datetime.now()) Traceback (most recent call last):   File "<stdin>", line 1, in <module>   File "/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/email    /utils.py", line 159, in formatdate     now = time.gmtime(timeval) TypeError: a float is required 

Answer 1

Here's some working code, broken down into simple pieces just for clarity:

>>> import datetime >>> import time >>> from email import utils >>> nowdt = datetime.datetime.now() >>> nowtuple = nowdt.timetuple() >>> nowtimestamp = time.mktime(nowtuple) >>> utils.formatdate(nowtimestamp) 'Tue, 10 Aug 2010 20:43:53 -0000' 

Explanation: email.utils.formatdate wants a timestamp -- i.e., a float with seconds (and fraction thereof) since the epoch. A datetime instance doesn't give you a timestamp directly -- but, it can give you a time-tuple with the timetuple method, and time.mktime of course can then make a timestamp from such a tuple.

EDIT: In Python 3.3 and newer you can do the same in less steps:

>>> import datetime >>> from email import utils >>> nowdt = datetime.datetime.now() >>> utils.format_datetime(nowdt) 'Tue, 10 Feb 2020 10:06:53 -0000' 

See format_datetime docs for details on usage.