[1.11.x] Refs #27935 -- Fixed BrinIndex.max_name_length if a project's default database isn't PostgreSQL.

Thanks Florian Apolloner for the report.

Backport of 2867b7eb4b8477710f11707d4b975db10e5f91a7 from master

1 files changed, 5 insertions, 10 deletions

diff --git a/django/contrib/postgres/indexes.py b/django/contrib/postgres/indexes.py
index 785f1d8020..750adc26d4 100644
--- a/django/contrib/postgres/indexes.py
+++ b/django/contrib/postgres/indexes.py
@@ -1,14 +1,17 @@
 from __future__ import unicode_literals
 
-from django.db import connection
 from django.db.models import Index
-from django.utils.functional import cached_property
 
 __all__ = ['BrinIndex', 'GinIndex']
 
 
 class BrinIndex(Index):
     suffix = 'brin'
+    # Allow an index name longer than 30 characters since the suffix is 4
+    # characters (usual limit is 3). Since this index can only be used on
+    # PostgreSQL, the 30 character limit for cross-database compatibility isn't
+    # applicable.
+    max_name_length = 31
 
     def __init__(self, fields=[], name=None, pages_per_range=None):
         if pages_per_range is not None and pages_per_range <= 0:
@@ -38,14 +41,6 @@ class BrinIndex(Index):
                 schema_editor.quote_value(self.pages_per_range)) + parameters['extra']
         return parameters
 
-    @cached_property
-    def max_name_length(self):
-        # Allow an index name longer than 30 characters since the suffix
-        # is 4 characters (usual limit is 3). Since this index can only be
-        # used on PostgreSQL, the 30 character limit for cross-database
-        # compatibility isn't applicable.
-        return connection.ops.max_name_length()
-
 
 class GinIndex(Index):
     suffix = 'gin'