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thirdparty/google_appengine/lib/django/tests/modeltests/many_to_many/models.py
changeset 109 620f9b141567 
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/thirdparty/google_appengine/lib/django/tests/modeltests/many_to_many/models.py	Tue Aug 26 21:49:54 2008 +0000
@@ -0,0 +1,258 @@
+"""
+5. Many-to-many relationships
+
+To define a many-to-many relationship, use ManyToManyField().
+
+In this example, an article can be published in multiple publications,
+and a publication has multiple articles.
+"""
+
+from django.db import models
+
+class Publication(models.Model):
+    title = models.CharField(maxlength=30)
+
+    def __str__(self):
+        return self.title
+
+    class Meta:
+        ordering = ('title',)
+
+class Article(models.Model):
+    headline = models.CharField(maxlength=100)
+    publications = models.ManyToManyField(Publication)
+
+    def __str__(self):
+        return self.headline
+
+    class Meta:
+        ordering = ('headline',)
+
+__test__ = {'API_TESTS':"""
+# Create a couple of Publications.
+>>> p1 = Publication(id=None, title='The Python Journal')
+>>> p1.save()
+>>> p2 = Publication(id=None, title='Science News')
+>>> p2.save()
+>>> p3 = Publication(id=None, title='Science Weekly')
+>>> p3.save()
+
+# Create an Article.
+>>> a1 = Article(id=None, headline='Django lets you build Web apps easily')
+>>> a1.save()
+
+# Associate the Article with a Publication.
+>>> a1.publications.add(p1)
+
+# Create another Article, and set it to appear in both Publications.
+>>> a2 = Article(id=None, headline='NASA uses Python')
+>>> a2.save()
+>>> a2.publications.add(p1, p2)
+>>> a2.publications.add(p3)
+
+# Adding a second time is OK
+>>> a2.publications.add(p3)
+
+# Add a Publication directly via publications.add by using keyword arguments.
+>>> new_publication = a2.publications.create(title='Highlights for Children')
+
+# Article objects have access to their related Publication objects.
+>>> a1.publications.all()
+[<Publication: The Python Journal>]
+>>> a2.publications.all()
+[<Publication: Highlights for Children>, <Publication: Science News>, <Publication: Science Weekly>, <Publication: The Python Journal>]
+
+# Publication objects have access to their related Article objects.
+>>> p2.article_set.all()
+[<Article: NASA uses Python>]
+>>> p1.article_set.all()
+[<Article: Django lets you build Web apps easily>, <Article: NASA uses Python>]
+>>> Publication.objects.get(id=4).article_set.all()
+[<Article: NASA uses Python>]
+
+# We can perform kwarg queries across m2m relationships
+>>> Article.objects.filter(publications__id__exact=1)
+[<Article: Django lets you build Web apps easily>, <Article: NASA uses Python>]
+>>> Article.objects.filter(publications__pk=1)
+[<Article: Django lets you build Web apps easily>, <Article: NASA uses Python>]
+>>> Article.objects.filter(publications=1)
+[<Article: Django lets you build Web apps easily>, <Article: NASA uses Python>]
+>>> Article.objects.filter(publications=p1)
+[<Article: Django lets you build Web apps easily>, <Article: NASA uses Python>]
+
+>>> Article.objects.filter(publications__title__startswith="Science")
+[<Article: NASA uses Python>, <Article: NASA uses Python>]
+
+>>> Article.objects.filter(publications__title__startswith="Science").distinct()
+[<Article: NASA uses Python>]
+
+# The count() function respects distinct() as well.
+>>> Article.objects.filter(publications__title__startswith="Science").count()
+2
+
+>>> Article.objects.filter(publications__title__startswith="Science").distinct().count()
+1
+
+>>> Article.objects.filter(publications__in=[1,2]).distinct()
+[<Article: Django lets you build Web apps easily>, <Article: NASA uses Python>]
+>>> Article.objects.filter(publications__in=[1,p2]).distinct()
+[<Article: Django lets you build Web apps easily>, <Article: NASA uses Python>]
+>>> Article.objects.filter(publications__in=[p1,p2]).distinct()
+[<Article: Django lets you build Web apps easily>, <Article: NASA uses Python>]
+
+# Reverse m2m queries are supported (i.e., starting at the table that doesn't
+# have a ManyToManyField).
+>>> Publication.objects.filter(id__exact=1)
+[<Publication: The Python Journal>]
+>>> Publication.objects.filter(pk=1)
+[<Publication: The Python Journal>]
+
+>>> Publication.objects.filter(article__headline__startswith="NASA")
+[<Publication: Highlights for Children>, <Publication: Science News>, <Publication: Science Weekly>, <Publication: The Python Journal>]
+
+>>> Publication.objects.filter(article__id__exact=1)
+[<Publication: The Python Journal>]
+>>> Publication.objects.filter(article__pk=1)
+[<Publication: The Python Journal>]
+>>> Publication.objects.filter(article=1)
+[<Publication: The Python Journal>]
+>>> Publication.objects.filter(article=a1)
+[<Publication: The Python Journal>]
+
+>>> Publication.objects.filter(article__in=[1,2]).distinct()
+[<Publication: Highlights for Children>, <Publication: Science News>, <Publication: Science Weekly>, <Publication: The Python Journal>]
+>>> Publication.objects.filter(article__in=[1,a2]).distinct()
+[<Publication: Highlights for Children>, <Publication: Science News>, <Publication: Science Weekly>, <Publication: The Python Journal>]
+>>> Publication.objects.filter(article__in=[a1,a2]).distinct()
+[<Publication: Highlights for Children>, <Publication: Science News>, <Publication: Science Weekly>, <Publication: The Python Journal>]
+
+# If we delete a Publication, its Articles won't be able to access it.
+>>> p1.delete()
+>>> Publication.objects.all()
+[<Publication: Highlights for Children>, <Publication: Science News>, <Publication: Science Weekly>]
+>>> a1 = Article.objects.get(pk=1)
+>>> a1.publications.all()
+[]
+
+# If we delete an Article, its Publications won't be able to access it.
+>>> a2.delete()
+>>> Article.objects.all()
+[<Article: Django lets you build Web apps easily>]
+>>> p2.article_set.all()
+[]
+
+# Adding via the 'other' end of an m2m
+>>> a4 = Article(headline='NASA finds intelligent life on Earth')
+>>> a4.save()
+>>> p2.article_set.add(a4)
+>>> p2.article_set.all()
+[<Article: NASA finds intelligent life on Earth>]
+>>> a4.publications.all()
+[<Publication: Science News>]
+
+# Adding via the other end using keywords
+>>> new_article = p2.article_set.create(headline='Oxygen-free diet works wonders')
+>>> p2.article_set.all()
+[<Article: NASA finds intelligent life on Earth>, <Article: Oxygen-free diet works wonders>]
+>>> a5 = p2.article_set.all()[1]
+>>> a5.publications.all()
+[<Publication: Science News>]
+
+# Removing publication from an article:
+>>> a4.publications.remove(p2)
+>>> p2.article_set.all()
+[<Article: Oxygen-free diet works wonders>]
+>>> a4.publications.all()
+[]
+
+# And from the other end
+>>> p2.article_set.remove(a5)
+>>> p2.article_set.all()
+[]
+>>> a5.publications.all()
+[]
+
+# Relation sets can be assigned. Assignment clears any existing set members
+>>> p2.article_set = [a4, a5]
+>>> p2.article_set.all()
+[<Article: NASA finds intelligent life on Earth>, <Article: Oxygen-free diet works wonders>]
+>>> a4.publications.all()
+[<Publication: Science News>]
+>>> a4.publications = [p3]
+>>> p2.article_set.all()
+[<Article: Oxygen-free diet works wonders>]
+>>> a4.publications.all()
+[<Publication: Science Weekly>]
+
+# Relation sets can be cleared:
+>>> p2.article_set.clear()
+>>> p2.article_set.all()
+[]
+>>> a4.publications.all()
+[<Publication: Science Weekly>]
+
+# And you can clear from the other end
+>>> p2.article_set.add(a4, a5)
+>>> p2.article_set.all()
+[<Article: NASA finds intelligent life on Earth>, <Article: Oxygen-free diet works wonders>]
+>>> a4.publications.all()
+[<Publication: Science News>, <Publication: Science Weekly>]
+>>> a4.publications.clear()
+>>> a4.publications.all()
+[]
+>>> p2.article_set.all()
+[<Article: Oxygen-free diet works wonders>]
+
+# Relation sets can also be set using primary key values
+>>> p2.article_set = [a4.id, a5.id]
+>>> p2.article_set.all()
+[<Article: NASA finds intelligent life on Earth>, <Article: Oxygen-free diet works wonders>]
+>>> a4.publications.all()
+[<Publication: Science News>]
+>>> a4.publications = [p3.id]
+>>> p2.article_set.all()
+[<Article: Oxygen-free diet works wonders>]
+>>> a4.publications.all()
+[<Publication: Science Weekly>]
+
+# Recreate the article and Publication we have deleted.
+>>> p1 = Publication(id=None, title='The Python Journal')
+>>> p1.save()
+>>> a2 = Article(id=None, headline='NASA uses Python')
+>>> a2.save()
+>>> a2.publications.add(p1, p2, p3)
+
+# Bulk delete some Publications - references to deleted publications should go
+>>> Publication.objects.filter(title__startswith='Science').delete()
+>>> Publication.objects.all()
+[<Publication: Highlights for Children>, <Publication: The Python Journal>]
+>>> Article.objects.all()
+[<Article: Django lets you build Web apps easily>, <Article: NASA finds intelligent life on Earth>, <Article: NASA uses Python>, <Article: Oxygen-free diet works wonders>]
+>>> a2.publications.all()
+[<Publication: The Python Journal>]
+
+# Bulk delete some articles - references to deleted objects should go
+>>> q = Article.objects.filter(headline__startswith='Django')
+>>> print q
+[<Article: Django lets you build Web apps easily>]
+>>> q.delete()
+
+# After the delete, the QuerySet cache needs to be cleared, and the referenced objects should be gone
+>>> print q
+[]
+>>> p1.article_set.all()
+[<Article: NASA uses Python>]
+
+# An alternate to calling clear() is to assign the empty set
+>>> p1.article_set = []
+>>> p1.article_set.all()
+[]
+
+>>> a2.publications = [p1, new_publication]
+>>> a2.publications.all()
+[<Publication: Highlights for Children>, <Publication: The Python Journal>]
+>>> a2.publications = []
+>>> a2.publications.all()
+[]
+
+"""}
py_tasks_melange