Django-rest-framework: No support for unix epoch timestamp for DateTimeField

[Alig1493]

Checklist

• [x] I have verified that that issue exists against the master branch of Django REST framework.
• [x] I have searched for similar issues in both open and closed tickets and cannot find a duplicate.
• [x] This is not a usage question. (Those should be directed to the discussion group instead.)
• [x] This cannot be dealt with as a third party library. (We prefer new functionality to be in the form of third party libraries where possible.)
• [x] I have reduced the issue to the simplest possible case.
• [x] I have included a failing test as a pull request. (If you are unable to do so we can still accept the issue.)

Steps to reproduce

• Create a serializer with DateTimeField

class DateSerializer(serializers.Serializer):

    date = fields.DateTimeField()

• Pass UNIX epoch timestamp
  python shell >> a = DateSerializer(data={'date':'1508239944313'})
• Validate the serializer by calling is_valid()

Expected Result

• The serializer should validate the data

Actual Result

• The serializer raises error upon validation

More Information

There should be a way to validate unix epoch timestamp by using DateTimeField by including an extra input_formats argument like input_formats=['epoch_timestamp']

[carltongibson]

I think this is just a limitation of the underlying strftime() and strptime() Behavior. There's no format for Unix Time timestamps there.

Instead you'll need to create a custom field using datetime.datetime.fromtimestamp() (or similar) in to_internal_value.

[Alig1493]

@carltongibson I can make a patch for DRF to support this input format in DateTimeField. We can use datetime.datetime.fromtimestamp() to parse the timestamp input in DateTimeField.
What do you think?

[carltongibson]

I think this is better in user-land code. A custom field would be simple enough.

[Alig1493]

I also agree. But seems like this format can also be included in the DateTimeField as this format is commonly used.

[rpkilby]

I'm -0 on this change to DateTimeField. If this were to be accepted, I'd rather see it added as a separate TimestampField or something similar.

[aidin-leo]

please support epoch timestamp too!

[anudeepsamaiya]

@rpkilby @carltongibson Having something like TimestampField that serializes and deserializes the unix epoch timestamps is a very common use case, and providing support for it would be better than delegating it to user-land code.

I can raise a pull request if you are interested.