Cloned databases for running tests in parallel.

1 files changed, 28 insertions, 0 deletions

diff --git a/django/db/backends/postgresql/creation.py b/django/db/backends/postgresql/creation.py
index 13eea0d3b7..dcb0430f1b 100644
--- a/django/db/backends/postgresql/creation.py
+++ b/django/db/backends/postgresql/creation.py
@@ -1,3 +1,5 @@
+import sys
+
 from django.db.backends.base.creation import BaseDatabaseCreation
 
 
@@ -11,3 +13,29 @@ class DatabaseCreation(BaseDatabaseCreation):
         if test_settings['CHARSET']:
             return "WITH ENCODING '%s'" % test_settings['CHARSET']
         return ''
+
+    def _clone_test_db(self, number, verbosity, keepdb=False):
+        # CREATE DATABASE ... WITH TEMPLATE ... requires closing connections
+        # to the template database.
+        self.connection.close()
+
+        qn = self.connection.ops.quote_name
+        source_database_name = self.connection.settings_dict['NAME']
+        target_database_name = self.get_test_db_clone_settings(number)['NAME']
+
+        with self._nodb_connection.cursor() as cursor:
+            try:
+                cursor.execute("CREATE DATABASE %s WITH TEMPLATE %s" % (
+                    qn(target_database_name), qn(source_database_name)))
+            except Exception as e:
+                if keepdb:
+                    return
+                try:
+                    if verbosity >= 1:
+                        print("Destroying old test database '%s'..." % self.connection.alias)
+                    cursor.execute("DROP DATABASE %s" % qn(target_database_name))
+                    cursor.execute("CREATE DATABASE %s WITH TEMPLATE %s" % (
+                        qn(target_database_name), qn(source_database_name)))
+                except Exception as e:
+                    sys.stderr.write("Got an error cloning the test database: %s\n" % e)
+                    sys.exit(2)