Using UpdateView to create a new object from an existing one

Using Django Forms & APIs
1

Hello

I have a very complex Model for a StitchTechnique. I would like to offer the possibility to create a new object by modifying an existing instance. I have a view which has 2 different submit buttons. one is to update existing object, the other one is to save the object as a new one.

I have used the updateView and pass it the instance of the object to edit. I have a set of related modelForms and formsets which correspond to the Model for a stitchtechnique. I have automatic generation of id_field.

I have noticed that there is a save_as_new argument for InLineFormsets which seems to correspond to what I need. But is does not exist for Model form. SO I suspect I must handle it in my code. Should I just ignore the id in the post data and also all foreign key fields and just set them to None?

I thank you for your answer.

2

You might want to refer to the section on copying at Making queries | Django documentation | Django .

3

Thanks for your answer. But this relates to the model. My question is about the form. Because the get creates a form with an instance keyword arguments id fields etc are present in the post data. So I believe I must erase some of those data in the post or probably better ignore some fields in the form cleaning. AN my question is which fields should I ignore. I suspect id and all relation fields should be ignored in the form fields cleaning. But I would appreciate having confirmation form experts.

4

I think you should let Django ORM handle duplication. Manually modifying ID or foreign keys in POST data is risky and can break relationships between models and formsets.