Implemented multi-field ordering on search

tests/models.py

@@ -8,6 +8,7 @@ class MockModel(models.Model):
     foo = models.CharField(max_length=255, blank=True)
     pub_date = models.DateTimeField(default=datetime.datetime.now)
     value = models.IntegerField()
+    flag = models.BooleanField()
 
     def __unicode__(self):
         return self.user

tests/xapian_backend.py

@@ -19,6 +19,7 @@ class XapianMockSearchIndex(indexes.SearchIndex):
     name = indexes.CharField(model_attr='author')
     pub_date = indexes.DateField(model_attr='pub_date')
     value = indexes.IntegerField(model_attr='value')
+    flag = indexes.BooleanField(model_attr='flag')
 
 
 class XapianSearchSite(sites.SearchSite):
@@ -46,6 +47,7 @@ def setUp(self):
             mock.author = 'david%s' % i
             mock.pub_date = datetime.date(2009, 2, 25) - datetime.timedelta(days=i)
             mock.value = i * 5
+            mock.flag = bool(i % 2)
             self.sample_objs.append(mock)
 
     def tearDown(self):
@@ -89,15 +91,15 @@ def test_update(self):
         self.sb.update(self.msi, self.sample_objs) # Duplicates should be updated, not appended -- http://github.com/notanumber/xapian-haystack/issues/#issue/6
 
         self.assertEqual(len(self.xapian_search('')), 3)
-        self.assertEqual([dict(doc) for doc in self.xapian_search('')], [{'name': u'david1', 'text': u'Indexed!\n1', 'pub_date': u'2009-02-24T00:00:00', 'value': u'5', 'id': u'tests.mockmodel.1'}, {'name': u'david2', 'text': u'Indexed!\n2', 'pub_date': u'2009-02-23T00:00:00', 'value': u'10', 'id': u'tests.mockmodel.2'}, {'name': u'david3', 'text': u'Indexed!\n3', 'pub_date': u'2009-02-22T00:00:00', 'value': u'15', 'id': u'tests.mockmodel.3'}])
+        self.assertEqual([dict(doc) for doc in self.xapian_search('')], [{'flag': u'true', 'name': u'david1', 'text': u'Indexed!\n1', 'pub_date': u'2009-02-24T00:00:00', 'value': u'5', 'id': u'tests.mockmodel.1'}, {'flag': u'false', 'name': u'david2', 'text': u'Indexed!\n2', 'pub_date': u'2009-02-23T00:00:00', 'value': u'10', 'id': u'tests.mockmodel.2'}, {'flag': u'true', 'name': u'david3', 'text': u'Indexed!\n3', 'pub_date': u'2009-02-22T00:00:00', 'value': u'15', 'id': u'tests.mockmodel.3'}])
 
     def test_remove(self):
         self.sb.update(self.msi, self.sample_objs)
         self.assertEqual(len(self.xapian_search('')), 3)
 
         self.sb.remove(self.sample_objs[0])
         self.assertEqual(len(self.xapian_search('')), 2)
-        self.assertEqual([dict(doc) for doc in self.xapian_search('')], [{'name': u'david2', 'text': u'Indexed!\n2', 'pub_date': u'2009-02-23T00:00:00', 'value': u'10', 'id': u'tests.mockmodel.2'}, {'name': u'david3', 'text': u'Indexed!\n3', 'pub_date': u'2009-02-22T00:00:00', 'value': u'15', 'id': u'tests.mockmodel.3'}])
+        self.assertEqual([dict(doc) for doc in self.xapian_search('')], [{'flag': u'false', 'name': u'david2', 'text': u'Indexed!\n2', 'pub_date': u'2009-02-23T00:00:00', 'value': u'10', 'id': u'tests.mockmodel.2'}, {'flag': u'true', 'name': u'david3', 'text': u'Indexed!\n3', 'pub_date': u'2009-02-22T00:00:00', 'value': u'15', 'id': u'tests.mockmodel.3'}])
 
     def test_clear(self):
         self.sb.update(self.msi, self.sample_objs)
@@ -178,7 +180,7 @@ def test_more_like_this(self):
 
         results = self.sb.more_like_this(self.sample_objs[0])
         self.assertEqual(results['hits'], 2)
-        self.assertEqual([result.pk for result in results['results']], [u'2', u'3'])
+        self.assertEqual([result.pk for result in results['results']], [u'3', u'2'])
 
     def test_document_count(self):
         self.sb.update(self.msi, self.sample_objs)
@@ -193,10 +195,10 @@ def test_delete_index(self):
 
     def test_order_by(self):
         self.sb.update(self.msi, self.sample_objs)
-        
+
         results = self.sb.search('*', sort_by=['pub_date'])
         self.assertEqual([result.pk for result in results['results']], [u'1', u'2', u'3'])
-        
+
         results = self.sb.search('*', sort_by=['-pub_date'])
         self.assertEqual([result.pk for result in results['results']], [u'3', u'2', u'1'])
 
@@ -205,13 +207,19 @@ def test_order_by(self):
 
         results = self.sb.search('*', sort_by=['-id'])
         self.assertEqual([result.pk for result in results['results']], [u'1', u'2', u'3'])
-    
+
         results = self.sb.search('*', sort_by=['value'])
         self.assertEqual([result.pk for result in results['results']], [u'3', u'2', u'1'])
 
         results = self.sb.search('*', sort_by=['-value'])
         self.assertEqual([result.pk for result in results['results']], [u'1', u'2', u'3'])
-
+
+        results = self.sb.search('*', sort_by=['flag', 'id'])
+        self.assertEqual([result.pk for result in results['results']], [u'3', u'1', u'2'])
+
+        results = self.sb.search('*', sort_by=['flag', '-id'])
+        self.assertEqual([result.pk for result in results['results']], [u'1', u'3', u'2'])
+
     def test__from_python(self):
         self.assertEqual(self.sb._from_python('abc'), u'abc')
         self.assertEqual(self.sb._from_python(1), u'1')

xapian_backend.py

@@ -305,16 +305,18 @@ def search(self, query_string, sort_by=None, start_offset=0, end_offset=DEFAULT_
 
         enquire = xapian.Enquire(database)
         enquire.set_query(query)
+        enquire.set_docid_order(enquire.ASCENDING)
 
         if sort_by:
-            if len(sort_by) > 1:
-                raise SearchBackendError("Xapian does not handle more than one field for ordering.")
-            if sort_by[0].startswith('-'):
-                reverse = True
-                sort_by[0] = sort_by[0][1:] # Strip the '-'
-            else:
-                reverse = False
-            enquire.set_sort_by_relevance_then_value(schema.get(sort_by[0], -1) + 1, reverse)
+            sorter = xapian.MultiValueSorter()
+            for sort_field in sort_by:
+                if sort_field.startswith('-'):
+                    reverse = False
+                    sort_field = sort_field[1:] # Strip the '-'
+                else:
+                    reverse = True # Reverse is inverted in Xapian -- http://trac.xapian.org/ticket/311
+                sorter.add(schema.get(sort_field, -1) + 1, reverse)
+            enquire.set_sort_by_key_then_relevance(sorter, True)
 
         matches = enquire.get_mset(start_offset, end_offset)
         results = self._process_results(matches, facets)
@@ -378,6 +380,7 @@ def more_like_this(self, model_instance):
         )
         enquire = xapian.Enquire(database)
         enquire.set_query(query)
+        enquire.set_docid_order(enquire.DONT_CARE)
         rset = xapian.RSet()
         for match in enquire.get_mset(0, DEFAULT_MAX_RESULTS):
             rset.add_document(match.get_docid())