Fixed #2217 -- Allowed raw objects to be used in __exact and __in query terms. Existing use of primary keys in query terms is preserved.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@3246 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/models/fields/related.py

@@ -78,6 +78,32 @@ class RelatedField(object):
         related = RelatedObject(other, cls, self)
         self.contribute_to_related_class(other, related)
 
+    def get_db_prep_lookup(self, lookup_type, value):
+        # If we are doing a lookup on a Related Field, we must be 
+        # comparing object instances. The value should be the PK of value, 
+        # not value itself.
+        def pk_trace(value):
+            # Value may be a primary key, or an object held in a relation. 
+            # If it is an object, then we need to get the primary key value for
+            # that object. In certain conditions (especially one-to-one relations),
+            # the primary key may itself be an object - so we need to keep drilling
+            # down until we hit a value that can be used for a comparison.
+            v = value
+            try:
+                while True:
+                    v = getattr(v, v._meta.pk.name)
+            except AttributeError:
+                pass
+            return v 
+            
+        if lookup_type == 'exact':
+            return [pk_trace(value)]
+        if lookup_type == 'in':
+            return [pk_trace(v) for v in value]
+        elif lookup_type == 'isnull':
+            return []
+        raise TypeError, "Related Field has invalid lookup: %s" % lookup_type
+            
     def _get_related_query_name(self, opts):
         # This method defines the name that can be used to identify this related object
         # in a table-spanning query. It uses the lower-cased object_name by default,

django/db/models/query.py

@@ -841,12 +841,14 @@ def lookup_inner(path, clause, value, opts, table, column):
         )
 
     if path:
+        # There are elements left in the path. More joins are required.
         if len(path) == 1 and path[0] in (new_opts.pk.name, None) \
             and clause in ('exact', 'isnull') and not join_required:
-            # If the last name query is for a key, and the search is for
+            # If the next and final name query is for a primary key, 
-            # isnull/exact, then the current (for N-1) or intermediate
+            # and the search is for isnull/exact, then the current 
-            # (for N-N) table can be used for the search - no need to join an
+            # (for N-1) or intermediate (for N-N) table can be used 
-            # extra table just to check the primary key.
+            # for the search - no need to join an extra table just 
+            # to check the primary key.
             new_table = current_table
         else:
             # There are 1 or more name queries pending, and we have ruled out
@@ -872,13 +874,41 @@ def lookup_inner(path, clause, value, opts, table, column):
         where.extend(where2)
         params.extend(params2)
     else:
-        # Evaluate clause on current table.
+        # No elements left in path. Current element is the element on which 
-        if name in (current_opts.pk.name, None) and clause in ('exact', 'isnull') and current_column:
+        # the search is being performed. 
-            # If this is an exact/isnull key search, and the last pass
+        
-            # found/introduced a current/intermediate table that we can use to
+        if join_required:
-            # optimize the query, then use that column name.
+            # Last query term is a RelatedObject 
+            if field.field.rel.multiple:    
+                # RelatedObject is from a 1-N relation.
+                # Join is required; query operates on joined table.
+                column = new_opts.pk.name            
+                joins[backend.quote_name(new_table)] = (
+                    backend.quote_name(new_opts.db_table),
+                    "INNER JOIN",
+                    "%s.%s = %s.%s" %
+                        (backend.quote_name(current_table),
+                        backend.quote_name(join_column),
+                        backend.quote_name(new_table),
+                        backend.quote_name(new_column))
+                )
+                current_table = new_table
+            else:
+                # RelatedObject is from a 1-1 relation, 
+                # No need to join; get the pk value from the related object, 
+                # and compare using that.
+                column = current_opts.pk.name
+        elif intermediate_table: 
+            # Last query term is a related object from an N-N relation.
+            # Join from intermediate table is sufficient.
+            column = join_column
+        elif name == current_opts.pk.name and clause in ('exact', 'isnull') and current_column:
+            # Last query term is for a primary key. If previous iterations 
+            # introduced a current/intermediate table that can be used to
+            # optimize the query, then use that table and column name.
             column = current_column
         else:
+            # Last query term was a normal field.
             column = field.column
 
         where.append(get_where_clause(clause, current_table + '.', column, value))

django/db/models/related.py

@@ -70,6 +70,10 @@ class RelatedObject(object):
         else:
             return [None] * self.field.rel.num_in_admin
 
+    def get_db_prep_lookup(self, lookup_type, value):
+        # Defer to the actual field definition for db prep
+        return self.field.get_db_prep_lookup(lookup_type, value)
+        
     def editable_fields(self):
         "Get the fields in this class that should be edited inline."
         return [f for f in self.opts.fields + self.opts.many_to_many if f.editable and f != self.field]

tests/modeltests/many_to_many/models.py

@@ -75,6 +75,10 @@ API_TESTS = """
 [<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>]
@@ -89,6 +93,13 @@ API_TESTS = """
 >>> 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)
@@ -101,9 +112,19 @@ API_TESTS = """
 
 >>> 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()

tests/modeltests/many_to_one/models.py

@@ -151,10 +151,20 @@ False
 [<Article: John's second story>, <Article: This is a test>]
 
 # Find all Articles for the Reporter whose ID is 1.
+# Use direct ID check, pk check, and object comparison 
 >>> Article.objects.filter(reporter__id__exact=1)
 [<Article: John's second story>, <Article: This is a test>]
 >>> Article.objects.filter(reporter__pk=1)
 [<Article: John's second story>, <Article: This is a test>]
+>>> Article.objects.filter(reporter=1)
+[<Article: John's second story>, <Article: This is a test>]
+>>> Article.objects.filter(reporter=r)
+[<Article: John's second story>, <Article: This is a test>]
+
+>>> Article.objects.filter(reporter__in=[1,2]).distinct()
+[<Article: John's second story>, <Article: Paul's story>, <Article: This is a test>]
+>>> Article.objects.filter(reporter__in=[r,r2]).distinct()
+[<Article: John's second story>, <Article: Paul's story>, <Article: This is a test>]
 
 # You need two underscores between "reporter" and "id" -- not one.
 >>> Article.objects.filter(reporter_id__exact=1)
@@ -168,10 +178,6 @@ Traceback (most recent call last):
     ...
 TypeError: Cannot resolve keyword 'reporter_id' into field
 
-# "pk" shortcut syntax works in a related context, too.
->>> Article.objects.filter(reporter__pk=1)
-[<Article: John's second story>, <Article: This is a test>]
-
 # You can also instantiate an Article by passing
 # the Reporter's ID instead of a Reporter object.
 >>> a3 = Article(id=None, headline="This is a test", pub_date=datetime(2005, 7, 27), reporter_id=r.id)
@@ -200,6 +206,18 @@ TypeError: Cannot resolve keyword 'reporter_id' into field
 [<Reporter: John Smith>]
 >>> Reporter.objects.filter(article__pk=1)
 [<Reporter: John Smith>]
+>>> Reporter.objects.filter(article=1)
+[<Reporter: John Smith>]
+>>> Reporter.objects.filter(article=a)
+[<Reporter: John Smith>]
+
+>>> Reporter.objects.filter(article__in=[1,4]).distinct()
+[<Reporter: John Smith>]
+>>> Reporter.objects.filter(article__in=[1,a3]).distinct()
+[<Reporter: John Smith>]
+>>> Reporter.objects.filter(article__in=[a,a3]).distinct()
+[<Reporter: John Smith>]
+
 >>> Reporter.objects.filter(article__headline__startswith='This')
 [<Reporter: John Smith>, <Reporter: John Smith>, <Reporter: John Smith>]
 >>> Reporter.objects.filter(article__headline__startswith='This').distinct()
@@ -216,6 +234,8 @@ TypeError: Cannot resolve keyword 'reporter_id' into field
 [<Reporter: John Smith>, <Reporter: John Smith>, <Reporter: John Smith>, <Reporter: John Smith>]
 >>> Reporter.objects.filter(article__reporter__first_name__startswith='John').distinct()
 [<Reporter: John Smith>]
+>>> Reporter.objects.filter(article__reporter__exact=r).distinct()
+[<Reporter: John Smith>]
 
 # If you delete a reporter, his articles will be deleted.
 >>> Article.objects.all()

tests/modeltests/one_to_one/models.py

@@ -94,6 +94,12 @@ DoesNotExist: Restaurant matching query does not exist.
 <Restaurant: Demon Dogs the restaurant>
 >>> Restaurant.objects.get(place__exact=1)
 <Restaurant: Demon Dogs the restaurant>
+>>> Restaurant.objects.get(place__exact=p1)
+<Restaurant: Demon Dogs the restaurant>
+>>> Restaurant.objects.get(place=1)
+<Restaurant: Demon Dogs the restaurant>
+>>> Restaurant.objects.get(place=p1)
+<Restaurant: Demon Dogs the restaurant>
 >>> Restaurant.objects.get(place__pk=1)
 <Restaurant: Demon Dogs the restaurant>
 >>> Restaurant.objects.get(place__name__startswith="Demon")
@@ -105,8 +111,18 @@ DoesNotExist: Restaurant matching query does not exist.
 <Place: Demon Dogs the place>
 >>> Place.objects.get(restaurant__place__exact=1)
 <Place: Demon Dogs the place>
+>>> Place.objects.get(restaurant__place__exact=p1)
+<Place: Demon Dogs the place>
 >>> Place.objects.get(restaurant__pk=1)
 <Place: Demon Dogs the place>
+>>> Place.objects.get(restaurant=1)
+<Place: Demon Dogs the place>
+>>> Place.objects.get(restaurant=r)
+<Place: Demon Dogs the place>
+>>> Place.objects.get(restaurant__exact=1)
+<Place: Demon Dogs the place>
+>>> Place.objects.get(restaurant__exact=r)
+<Place: Demon Dogs the place>
 
 # Add a Waiter to the Restaurant.
 >>> w = r.waiter_set.create(name='Joe')
@@ -115,14 +131,22 @@ DoesNotExist: Restaurant matching query does not exist.
 <Waiter: Joe the waiter at Demon Dogs the restaurant>
 
 # Query the waiters
+>>> Waiter.objects.filter(restaurant__place__pk=1)
+[<Waiter: Joe the waiter at Demon Dogs the restaurant>]
 >>> Waiter.objects.filter(restaurant__place__exact=1)
 [<Waiter: Joe the waiter at Demon Dogs the restaurant>]
+>>> Waiter.objects.filter(restaurant__place__exact=p1)
+[<Waiter: Joe the waiter at Demon Dogs the restaurant>]
 >>> Waiter.objects.filter(restaurant__pk=1)
 [<Waiter: Joe the waiter at Demon Dogs the restaurant>]
 >>> Waiter.objects.filter(id__exact=1)
 [<Waiter: Joe the waiter at Demon Dogs the restaurant>]
 >>> Waiter.objects.filter(pk=1)
 [<Waiter: Joe the waiter at Demon Dogs the restaurant>]
+>>> Waiter.objects.filter(restaurant=1)
+[<Waiter: Joe the waiter at Demon Dogs the restaurant>]
+>>> Waiter.objects.filter(restaurant=r)
+[<Waiter: Joe the waiter at Demon Dogs the restaurant>]
 
 # Delete the restaurant; the waiter should also be removed
 >>> r = Restaurant.objects.get(pk=1)