Django - How to reset model fields to their default value?

Question

What would be the most elegant\efficient way to reset all fields of a certain model instance back to their defaults?

Answer 1

I once did it this way. No better way I could think of.

from django.db.models.fields import NOT_PROVIDED

for f in instance._meta.fields:
    if f.default <> NOT_PROVIDED:
        setattr(instance, f.name, f.default)

# treatment of None values, in your words, to handle fields not marked with null=True
...
...
# treatment ends

instance.save()

Note: In my case all the fields, did have default value.

Hope it'll help. Happy Coding.

Answer 2

def reset( self, fields=[], exclude=[] ):

    fields = fields or filter( lambda x: x.name in fields, self._meta.fields )
    exclude.append( 'id' )        

    for f in filter( lambda x: x.name not in exclude, fields ):
        if getattr( f, 'auto_now_add', False ):
            continue

        if f.blank or f.has_default():
            setattr( self, f.name, f.get_default() )