Fixed #27060: Extended inspectdb so indexes are added to Meta.indexes.

AUTHORS

@@ -5,7 +5,7 @@ Here is an inevitably incomplete list of MUCH-APPRECIATED CONTRIBUTORS --
 people who have submitted patches, reported bugs, added translations, helped
 answer newbie questions, and generally made Django that much better:
 
-    Aaron Cannon <cannona@fireantproductions.com>
+    Aaron Cannon<cannona@fireantproductions.com>
     Aaron Swartz <http://www.aaronsw.com/>
     Aaron T. Myers <atmyers@gmail.com>
     Abeer Upadhyay <ab.esquarer@gmail.com>
@@ -288,6 +288,7 @@ answer newbie questions, and generally made Django that much better:
     Doug Beck <doug@douglasbeck.com>
     Doug Napoleone <doug@dougma.com>
     dready <wil@mojipage.com>
+    Drew Winstel <https://github.com/drewbrew>
     Durval Carvalho de Souza <dudurval2@gmail.com>
     dusk@woofle.net
     Dustyn Gibson <miigotu@gmail.com>
@@ -1049,7 +1050,7 @@ answer newbie questions, and generally made Django that much better:
     Zeynel Özdemir <ozdemir.zynl@gmail.com>
     Zlatko Mašek <zlatko.masek@gmail.com>
     zriv <https://github.com/zriv>
-    <Please alphabetize new entries>
+<Please alphabetize new entries>
 
 A big THANK YOU goes to:
 

django/contrib/gis/db/backends/spatialite/introspection.py

@@ -78,5 +78,6 @@ def get_constraints(self, cursor, table_name):
                 "foreign_key": None,
                 "check": False,
                 "index": True,
+                "type": "rtree",  # spatial enabled indexes are of type rtree
             }
         return constraints

django/core/management/commands/inspectdb.py

@@ -4,6 +4,7 @@
 from django.core.management.base import BaseCommand, CommandError
 from django.db import DEFAULT_DB_ALIAS, connections
 from django.db.models.constants import LOOKUP_SEP
+from django.db.models.indexes import Index
 
 
 class Command(BaseCommand):
@@ -378,8 +379,10 @@ def get_meta(
         to the given database table name.
         """
         unique_together = []
+        indexes = []
+        index_comments = []
         has_unsupported_constraint = False
-        for params in constraints.values():
+        for name, params in constraints.items():
             if params["unique"]:
                 columns = params["columns"]
                 if None in columns:
@@ -391,6 +394,32 @@ def get_meta(
                     unique_together.append(
                         str(tuple(column_to_field_name[c] for c in columns))
                     )
+            elif params["index"] and not params["primary_key"]:
+                columns = params["columns"]
+                orders = params.get("orders", [""] * len(columns))
+
+                field_names = [
+                    (
+                        f'{"-" if order.lower() == "desc" else ""}'
+                        f"{column_to_field_name[column]}"
+                    )
+                    for column, order in zip(columns, orders)
+                ]
+                index_str = f"models.Index(fields={field_names!r}, name={name!r})"
+                comment = ""
+                if params["type"] not in ["btree", Index.suffix]:
+                    comment = f'Index type is {params["type"]}'
+                if params["type"] in ["rtree", "spatial"] and len(columns) == 1:
+                    # assume this is a default spatial index, so let's make a note
+                    # of it and continue
+                    index_comments.append(
+                        "Skipped default spatial index for "
+                        f"{column_to_field_name[columns[0]]}"
+                    )
+                    indexes.append("")
+                    continue
+                indexes.append(index_str)
+                index_comments.append(comment)
         if is_view:
             managed_comment = "  # Created from a view. Don't remove."
         elif is_partition:
@@ -410,4 +439,15 @@ def get_meta(
             meta += ["        unique_together = %s" % tup]
         if comment:
             meta += [f"        db_table_comment = {comment!r}"]
+        if indexes:
+            meta.append("        indexes = (")
+            for line, comment in zip(indexes, index_comments):
+                if line:
+                    if comment:
+                        meta.append(f"            {line},  # {comment}")
+                    else:
+                        meta.append(f"            {line},")
+                else:
+                    meta.append(f"            # {comment}")
+            meta.append("        )")
         return meta

tests/gis_tests/inspectapp/models.py

@@ -21,3 +21,13 @@ class Fields3D(models.Model):
 
     class Meta:
         required_db_features = {"supports_3d_storage"}
+
+
+class Indexes(models.Model):
+    point = models.PointField()
+    name = models.CharField(max_length=5)
+    other = models.IntegerField()
+
+    class Meta:
+        required_db_features = {"supports_3d_storage"}
+        indexes = [models.Index(fields=["name", "other"], name="name_plus_other")]

tests/gis_tests/inspectapp/tests.py

@@ -57,6 +57,29 @@ def test_3d_columns(self):
             self.assertIn("line = models.GeometryField(", output)
             self.assertIn("poly = models.GeometryField(", output)
 
+    def test_indexes(self):
+        out = StringIO()
+        call_command(
+            "inspectdb",
+            table_name_filter=lambda tn: tn.startswith("inspectapp_indexes"),
+            stdout=out,
+        )
+        output = out.getvalue()
+        self.assertIn(
+            "        indexes = ",
+            output,
+            msg="inspectdb should generate indexes.",
+        )
+        # there should not be an index on a single-column geo field
+        # (assumed to be default)
+        index = "models.Index(fields=['point'], name="
+        self.assertNotIn(index, output)
+        # but our manually-created one should
+        self.assertIn(
+            "models.Index(fields=['name', 'other'], name='name_plus_other')",
+            output,
+        )
+
 
 @modify_settings(
     INSTALLED_APPS={"append": "django.contrib.gis"},

tests/inspectdb/models.py

@@ -147,3 +147,16 @@ class DbComment(models.Model):
     class Meta:
         db_table_comment = "Custom table comment"
         required_db_features = {"supports_comments"}
+
+
+class Indexes(models.Model):
+    field1 = models.IntegerField()
+    field2 = models.CharField(max_length=5)
+    from_field = models.IntegerField(unique=True, db_column="from")
+
+    class Meta:
+        indexes = [
+            models.Index(fields=["field1", "field2"], name="my_index"),
+            models.Index(fields=["field2", "-from_field"], name="my_other_index"),
+            models.Index(fields=["from_field"]),
+        ]

tests/inspectdb/tests.py

@@ -5,7 +5,12 @@
 from django.core.management import call_command
 from django.db import connection
 from django.db.backends.base.introspection import TableInfo
-from django.test import TestCase, TransactionTestCase, skipUnlessDBFeature
+from django.test import (
+    TestCase,
+    TransactionTestCase,
+    skipIfDBFeature,
+    skipUnlessDBFeature,
+)
 
 from .models import PeopleMoreData, test_collation
 
@@ -392,6 +397,42 @@ def test_unique_together_meta(self):
         # are given an integer suffix.
         self.assertIn("('non_unique_column', 'non_unique_column_0')", fields)
 
+    @skipUnlessDBFeature("supports_index_column_ordering")
+    def test_indexes(self):
+        out = StringIO()
+        call_command("inspectdb", "inspectdb_indexes", stdout=out)
+        output = out.getvalue()
+        self.assertIn("    indexes = (", output)
+        # our two named indexes are there
+        self.assertIn("my_index", output)
+        self.assertIn("my_other_index", output)
+        # we have a total of three indexes
+        matches = re.findall(r"models.Index\(", output)
+        self.assertEqual(len(matches), 3)
+        # and our three column defs are in place
+        self.assertIn("['from_field']", output)
+        self.assertIn("['field1', 'field2']", output)
+        # including descending sort
+        self.assertIn("['field2', '-from_field']", output)
+
+    @skipIfDBFeature("supports_index_column_ordering")
+    def test_indexes_no_order(self):
+        out = StringIO()
+        call_command("inspectdb", "inspectdb_indexes", stdout=out)
+        output = out.getvalue()
+        self.assertIn("    indexes = (", output)
+        # our two named indexes are there
+        self.assertIn("my_index", output)
+        self.assertIn("my_other_index", output)
+        # we have a total of three indexes
+        matches = re.findall(r"models.Index\(", output)
+        self.assertEqual(len(matches), 3)
+        # and our three column defs are in place
+        self.assertIn("['from_field']", output)
+        self.assertIn("['field1', 'field2']", output)
+        # ignoring the descending sort
+        self.assertIn("['field2', 'from_field']", output)
+
     @skipUnless(connection.vendor == "postgresql", "PostgreSQL specific SQL")
     def test_unsupported_unique_together(self):
         """Unsupported index types (COALESCE here) are skipped."""