Return None if the index cannot be created

Author: WaVEV

django_mongodb_backend/indexes.py

@@ -147,6 +147,9 @@ def search_index_data_types(self, field, db_type):
     def get_pymongo_index_model(
         self, model, schema_editor, field=None, unique=False, column_prefix=""
     ):
+        errors = self.check(model, schema_editor.connection)
+        if errors:
+            return None
         fields = {}
         for field_name, _ in self.fields_orders:
             field_ = model._meta.get_field(field_name)
@@ -227,6 +230,9 @@ def deconstruct(self):
     def get_pymongo_index_model(
         self, model, schema_editor, field=None, unique=False, column_prefix=""
     ):
+        errors = self.check(model, schema_editor.connection)
+        if errors:
+            return None
         similarities = (
             itertools.cycle([self.similarities])
             if isinstance(self.similarities, str)

django_mongodb_backend/schema.py

@@ -263,6 +263,9 @@ def alter_unique_together(
     def add_index(
         self, model, index, *, field=None, unique=False, column_prefix="", parent_model=None
     ):
+        # Check if the index can be created.
+        if hasattr(index, "check") and index.check(model, self.connection):
+            return
         idx = index.get_pymongo_index_model(
             model, schema_editor=self, field=field, unique=unique, column_prefix=column_prefix
         )

tests/indexes_/test_atlas_indexes.py

@@ -1,12 +1,11 @@
 from django.db import connection
-from django.test import TestCase, skipUnlessDBFeature
+from django.test import TestCase, skipIfDBFeature, skipUnlessDBFeature
 
 from django_mongodb_backend.indexes import SearchIndex, VectorSearchIndex
 
 from .models import Article
 
 
-@skipUnlessDBFeature("supports_atlas_search")
 class SearchIndexTests(TestCase):
     # Tests for creating, validating, and removing search indexes using Django's schema editor.
     available_apps = None
@@ -29,6 +28,7 @@ def assertAddRemoveIndex(self, editor, model, index):
             ),
         )
 
+    @skipUnlessDBFeature("supports_atlas_search")
     def test_simple(self):
         with connection.schema_editor() as editor:
             index = SearchIndex(
@@ -38,6 +38,23 @@ def test_simple(self):
             editor.add_index(index=index, model=Article)
             self.assertAddRemoveIndex(editor, Article, index)
 
+    @skipIfDBFeature("supports_atlas_search")
+    def test_index_not_created(self):
+        with connection.schema_editor() as editor:
+            index = SearchIndex(
+                name="recent_article_idx",
+                fields=["number"],
+            )
+            editor.add_index(index=index, model=Article)
+            self.assertNotIn(
+                index.name,
+                connection.introspection.get_constraints(
+                    cursor=None,
+                    table_name=Article._meta.db_table,
+                ),
+            )
+
+    @skipUnlessDBFeature("supports_atlas_search")
     def test_multiple_fields(self):
         with connection.schema_editor() as editor:
             index = SearchIndex(
@@ -80,7 +97,6 @@ def test_multiple_fields(self):
             self.assertAddRemoveIndex(editor, Article, index)
 
 
-@skipUnlessDBFeature("supports_atlas_search")
 class VectorSearchIndexTests(TestCase):
     # Tests for creating, validating, and removing vector search indexes
     # using Django's schema editor.
@@ -104,6 +120,7 @@ def assertAddRemoveIndex(self, editor, model, index):
             ),
         )
 
+    @skipUnlessDBFeature("supports_atlas_search")
     def test_deconstruct_default_similarity(self):
         index = VectorSearchIndex(
             name="recent_article_idx",
@@ -113,6 +130,23 @@ def test_deconstruct_default_similarity(self):
         new = VectorSearchIndex(*args, **kwargs)
         self.assertEqual(new.similarities, index.similarities)
 
+    @skipIfDBFeature("supports_atlas_search")
+    def test_index_not_created(self):
+        with connection.schema_editor() as editor:
+            index = VectorSearchIndex(
+                name="recent_article_idx",
+                fields=["number"],
+            )
+            editor.add_index(index=index, model=Article)
+            self.assertNotIn(
+                index.name,
+                connection.introspection.get_constraints(
+                    cursor=None,
+                    table_name=Article._meta.db_table,
+                ),
+            )
+
+    @skipUnlessDBFeature("supports_atlas_search")
     def test_deconstruct_with_similarities(self):
         index = VectorSearchIndex(
             name="recent_article_idx",
@@ -123,6 +157,7 @@ def test_deconstruct_with_similarities(self):
         new = VectorSearchIndex(*args, **kwargs)
         self.assertEqual(new.similarities, index.similarities)
 
+    @skipUnlessDBFeature("supports_atlas_search")
     def test_simple_vector_search(self):
         with connection.schema_editor() as editor:
             index = VectorSearchIndex(
@@ -132,6 +167,7 @@ def test_simple_vector_search(self):
             editor.add_index(index=index, model=Article)
             self.assertAddRemoveIndex(editor, Article, index)
 
+    @skipUnlessDBFeature("supports_atlas_search")
     def test_multiple_fields(self):
         with connection.schema_editor() as editor:
             index = VectorSearchIndex(