Django admin model field set to current user

Question

I have a model with field:

class MyModel(models.Model):
    name = models.CharField(max_length=50)
    created_by = models.ForeignKeyField(User)

Answer 1

To do that override the save_model method and set the created_by field to the current user.

class MyModelAdmin(admin.ModelAdmin):
    list_display= ("name",)
    fields = ("name",)

    def save_model(self, request, obj, form, change):             
        if not change: 
        # can use this condition also to set 'created_by'    
        # if not getattr(obj, 'created_by', None):            
            obj.created_by = request.user
        obj.save()

Answer 2

You have already set fields so that created_by does not appear in form in the Django admin.

Now you need to override save_model, and set the user before saving new objects.

class MyModelAdmin(admin.ModelAdmin):
    fields = ("name",)

    def save_model(self, request, obj, form, change):
        if not change:
            # the object is being created, so set the user
            obj.created_by = request.user
        obj.save()