from django.db import models class Author(models.Model): name = models.CharField(max_length=100) def __unicode__(self): return self.name class Book(models.Model): author = models.ForeignKey(Author) title = models.CharField(max_length=100) def __unicode__(self): return self.title class AuthorMeeting(models.Model): name = models.CharField(max_length=100) authors = models.ManyToManyField(Author) created = models.DateField(editable=False) def __unicode__(self): return self.name __test__ = {'API_TESTS': """ >>> from datetime import date >>> from django.newforms.models import modelformset_factory >>> qs = Author.objects.all() >>> AuthorFormSet = modelformset_factory(Author, extra=3) >>> formset = AuthorFormSet(queryset=qs) >>> for form in formset.forms: ... print form.as_p()

>>> data = { ... 'form-TOTAL_FORMS': '3', # the number of forms rendered ... 'form-INITIAL_FORMS': '0', # the number of forms with initial data ... 'form-MAX_FORMS': '0', # the max number of forms ... 'form-0-name': 'Charles Baudelaire', ... 'form-1-name': 'Arthur Rimbaud', ... 'form-2-name': '', ... } >>> formset = AuthorFormSet(data=data, queryset=qs) >>> formset.is_valid() True >>> formset.save() [, ] >>> for author in Author.objects.order_by('name'): ... print author.name Arthur Rimbaud Charles Baudelaire Gah! We forgot Paul Verlaine. Let's create a formset to edit the existing authors with an extra form to add him. We *could* pass in a queryset to restrict the Author objects we edit, but in this case we'll use it to display them in alphabetical order by name. >>> qs = Author.objects.order_by('name') >>> AuthorFormSet = modelformset_factory(Author, extra=1, can_delete=False) >>> formset = AuthorFormSet(queryset=qs) >>> for form in formset.forms: ... print form.as_p()

>>> data = { ... 'form-TOTAL_FORMS': '3', # the number of forms rendered ... 'form-INITIAL_FORMS': '2', # the number of forms with initial data ... 'form-MAX_FORMS': '0', # the max number of forms ... 'form-0-id': '2', ... 'form-0-name': 'Arthur Rimbaud', ... 'form-1-id': '1', ... 'form-1-name': 'Charles Baudelaire', ... 'form-2-name': 'Paul Verlaine', ... } >>> formset = AuthorFormSet(data=data, queryset=qs) >>> formset.is_valid() True # Only changed or new objects are returned from formset.save() >>> formset.save() [] >>> for author in Author.objects.order_by('name'): ... print author.name Arthur Rimbaud Charles Baudelaire Paul Verlaine This probably shouldn't happen, but it will. If an add form was marked for deltetion, make sure we don't save that form. >>> qs = Author.objects.order_by('name') >>> AuthorFormSet = modelformset_factory(Author, extra=1, can_delete=True) >>> formset = AuthorFormSet(queryset=qs) >>> for form in formset.forms: ... print form.as_p()

>>> data = { ... 'form-TOTAL_FORMS': '4', # the number of forms rendered ... 'form-INITIAL_FORMS': '3', # the number of forms with initial data ... 'form-MAX_FORMS': '0', # the max number of forms ... 'form-0-id': '2', ... 'form-0-name': 'Arthur Rimbaud', ... 'form-1-id': '1', ... 'form-1-name': 'Charles Baudelaire', ... 'form-2-id': '3', ... 'form-2-name': 'Paul Verlaine', ... 'form-3-name': 'Walt Whitman', ... 'form-3-DELETE': 'on', ... } >>> formset = AuthorFormSet(data=data, queryset=qs) >>> formset.is_valid() True # No objects were changed or saved so nothing will come back. >>> formset.save() [] >>> for author in Author.objects.order_by('name'): ... print author.name Arthur Rimbaud Charles Baudelaire Paul Verlaine Let's edit a record to ensure save only returns that one record. >>> data = { ... 'form-TOTAL_FORMS': '4', # the number of forms rendered ... 'form-INITIAL_FORMS': '3', # the number of forms with initial data ... 'form-MAX_FORMS': '0', # the max number of forms ... 'form-0-id': '2', ... 'form-0-name': 'Walt Whitman', ... 'form-1-id': '1', ... 'form-1-name': 'Charles Baudelaire', ... 'form-2-id': '3', ... 'form-2-name': 'Paul Verlaine', ... 'form-3-name': '', ... 'form-3-DELETE': '', ... } >>> formset = AuthorFormSet(data=data, queryset=qs) >>> formset.is_valid() True # One record has changed. >>> formset.save() [] Test the behavior of commit=False and save_m2m >>> meeting = AuthorMeeting.objects.create(created=date.today()) >>> meeting.authors = Author.objects.all() # create an Author instance to add to the meeting. >>> new_author = Author.objects.create(name=u'John Steinbeck') >>> AuthorMeetingFormSet = modelformset_factory(AuthorMeeting, extra=1, can_delete=True) >>> data = { ... 'form-TOTAL_FORMS': '2', # the number of forms rendered ... 'form-INITIAL_FORMS': '1', # the number of forms with initial data ... 'form-MAX_FORMS': '0', # the max number of forms ... 'form-0-id': '1', ... 'form-0-name': '2nd Tuesday of the Week Meeting', ... 'form-0-authors': [2, 1, 3, 4], ... 'form-1-name': '', ... 'form-1-authors': '', ... 'form-1-DELETE': '', ... } >>> formset = AuthorMeetingFormSet(data=data, queryset=AuthorMeeting.objects.all()) >>> formset.is_valid() True >>> instances = formset.save(commit=False) >>> for instance in instances: ... instance.created = date.today() ... instance.save() >>> formset.save_m2m() >>> instances[0].authors.all() [, , , ] # delete the author we created to allow later tests to continue working. >>> new_author.delete() Test the behavior of max_num with model formsets. It should properly limit the queryset to reduce the amount of objects being pulled in when not being used. >>> qs = Author.objects.order_by('name') >>> AuthorFormSet = modelformset_factory(Author, max_num=2) >>> formset = AuthorFormSet(queryset=qs) >>> formset.initial [{'id': 1, 'name': u'Charles Baudelaire'}, {'id': 3, 'name': u'Paul Verlaine'}] >>> AuthorFormSet = modelformset_factory(Author, max_num=3) >>> formset = AuthorFormSet(queryset=qs) >>> formset.initial [{'id': 1, 'name': u'Charles Baudelaire'}, {'id': 3, 'name': u'Paul Verlaine'}, {'id': 2, 'name': u'Walt Whitman'}] # Inline Formsets ############################################################ We can also create a formset that is tied to a parent model. This is how the admin system's edit inline functionality works. >>> from django.newforms.models import inlineformset_factory >>> AuthorBooksFormSet = inlineformset_factory(Author, Book, can_delete=False, extra=3) >>> author = Author.objects.get(name='Charles Baudelaire') >>> formset = AuthorBooksFormSet(instance=author) >>> for form in formset.forms: ... print form.as_p()

>>> data = { ... 'book_set-TOTAL_FORMS': '3', # the number of forms rendered ... 'book_set-INITIAL_FORMS': '0', # the number of forms with initial data ... 'book_set-MAX_FORMS': '0', # the max number of forms ... 'book_set-0-title': 'Les Fleurs du Mal', ... 'book_set-1-title': '', ... 'book_set-2-title': '', ... } >>> formset = AuthorBooksFormSet(data, instance=author) >>> formset.is_valid() True >>> formset.save() [] >>> for book in author.book_set.all(): ... print book.title Les Fleurs du Mal Now that we've added a book to Charles Baudelaire, let's try adding another one. This time though, an edit form will be available for every existing book. >>> AuthorBooksFormSet = inlineformset_factory(Author, Book, can_delete=False, extra=2) >>> author = Author.objects.get(name='Charles Baudelaire') >>> formset = AuthorBooksFormSet(instance=author) >>> for form in formset.forms: ... print form.as_p()

>>> data = { ... 'book_set-TOTAL_FORMS': '3', # the number of forms rendered ... 'book_set-INITIAL_FORMS': '1', # the number of forms with initial data ... 'book_set-MAX_FORMS': '0', # the max number of forms ... 'book_set-0-id': '1', ... 'book_set-0-title': 'Les Fleurs du Mal', ... 'book_set-1-title': 'Le Spleen de Paris', ... 'book_set-2-title': '', ... } >>> formset = AuthorBooksFormSet(data, instance=author) >>> formset.is_valid() True >>> formset.save() [] As you can see, 'Le Spleen de Paris' is now a book belonging to Charles Baudelaire. >>> for book in author.book_set.order_by('title'): ... print book.title Le Spleen de Paris Les Fleurs du Mal The save_as_new parameter lets you re-associate the data to a new instance. This is used in the admin for save_as functionality. >>> data = { ... 'book_set-TOTAL_FORMS': '3', # the number of forms rendered ... 'book_set-INITIAL_FORMS': '2', # the number of forms with initial data ... 'book_set-MAX_FORMS': '0', # the max number of forms ... 'book_set-0-id': '1', ... 'book_set-0-title': 'Les Fleurs du Mal', ... 'book_set-1-id': '2', ... 'book_set-1-title': 'Le Spleen de Paris', ... 'book_set-2-title': '', ... } >>> formset = AuthorBooksFormSet(data, instance=Author(), save_as_new=True) >>> formset.is_valid() True >>> new_author = Author.objects.create(name='Charles Baudelaire') >>> formset.instance = new_author >>> [book for book in formset.save() if book.author.pk == new_author.pk] [, ] """}