Relax the UUID regex

Apparently PG does not validate against RFC 4122. The intent of the original
patch is just to protect against PG errors (which potentially breaks txns, etc)
because of bad user input, so we shouldn't try any harder than PG itself.

Closes #17931

2 files changed, 9 insertions, 12 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/uuid.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/uuid.rb
index 033e0324bb..97b4fd3d08 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/uuid.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/uuid.rb
@@ -3,14 +3,7 @@ module ActiveRecord
     module PostgreSQL
       module OID # :nodoc:
         class Uuid < Type::Value # :nodoc:
-          RFC_4122 = %r{\A\{?[a-fA-F0-9]{4}-?
-                             [a-fA-F0-9]{4}-?
-                             [a-fA-F0-9]{4}-?
-                             [1-5][a-fA-F0-9]{3}-?
-                             [8-Bab][a-fA-F0-9]{3}-?
-                             [a-fA-F0-9]{4}-?
-                             [a-fA-F0-9]{4}-?
-                             [a-fA-F0-9]{4}-?\}?\z}x
+          ACCEPTABLE_UUID = %r{\A\{?([a-fA-F0-9]{4}-?){8}\}?\z}x
 
           alias_method :type_cast_for_database, :type_cast_from_database
 
@@ -19,7 +12,7 @@ module ActiveRecord
           end
 
           def type_cast(value)
-            value.to_s[RFC_4122, 0]
+            value.to_s[ACCEPTABLE_UUID, 0]
           end
         end
       end
diff --git a/activerecord/test/cases/adapters/postgresql/uuid_test.rb b/activerecord/test/cases/adapters/postgresql/uuid_test.rb
index fac21996ed..7b7532993c 100644
--- a/activerecord/test/cases/adapters/postgresql/uuid_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/uuid_test.rb
@@ -69,13 +69,18 @@ class PostgresqlUUIDTest < ActiveRecord::TestCase
     assert_equal 'foobar', uuid.guid_before_type_cast
   end
 
-  def test_rfc_4122_regex
+  def test_acceptable_uuid_regex
     # Valid uuids
     ['A0EEBC99-9C0B-4EF8-BB6D-6BB9BD380A11',
      '{a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11}',
      'a0eebc999c0b4ef8bb6d6bb9bd380a11',
      'a0ee-bc99-9c0b-4ef8-bb6d-6bb9-bd38-0a11',
-     '{a0eebc99-9c0b4ef8-bb6d6bb9-bd380a11}'].each do |valid_uuid|
+     '{a0eebc99-9c0b4ef8-bb6d6bb9-bd380a11}',
+     # The following is not a valid RFC 4122 UUID, but PG doesn't seem to care,
+     # so we shouldn't block it either. (Pay attention to "fb6d" – the "f" here
+     # is invalid – it must be one of 8, 9, A, B, a, b according to the spec.)
+     '{a0eebc99-9c0b-4ef8-fb6d-6bb9bd380a11}',
+    ].each do |valid_uuid|
       uuid = UUIDType.new guid: valid_uuid
       assert_not_nil uuid.guid
     end
@@ -87,7 +92,6 @@ class PostgresqlUUIDTest < ActiveRecord::TestCase
      0.0,
      true,
      'Z0000C99-9C0B-4EF8-BB6D-6BB9BD380A11',
-     '{a0eebc99-9c0b-4ef8-fb6d-6bb9bd380a11}',
      'a0eebc999r0b4ef8ab6d6bb9bd380a11',
      'a0ee-bc99------4ef8-bb6d-6bb9-bd38-0a11',
      '{a0eebc99-bb6d6bb9-bd380a11}'].each do |invalid_uuid|