From 73ca3932d3669f7a6f9bb722a6abaedb75f66929 Mon Sep 17 00:00:00 2001 From: Damon McCormick + Cameron Walters Date: Tue, 10 May 2011 16:41:05 -0700 Subject: Make ToSql more thread safe. Because the ToSql visitor instance is shared across all threads, there is a race condition around column types for binary nodes. It's possible, for instance, to end up with ActiveRecord converting a string value in the final SQL to an integer during heavy concurrent operations. --- lib/arel/visitors/to_sql.rb | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'lib/arel/visitors') diff --git a/lib/arel/visitors/to_sql.rb b/lib/arel/visitors/to_sql.rb index 73319364d5..4de497a17c 100644 --- a/lib/arel/visitors/to_sql.rb +++ b/lib/arel/visitors/to_sql.rb @@ -8,14 +8,13 @@ module Arel @engine = engine @connection = nil @pool = nil - @last_column = nil @quoted_tables = {} @quoted_columns = {} end def accept object - @last_column = nil - @pool = @engine.connection_pool + Thread.current[:arel_visitors_to_sql_last_column] = nil + @pool = @engine.connection_pool @pool.with_connection do |conn| @connection = conn super @@ -356,7 +355,7 @@ key on UpdateManager using UpdateManager#key= end def visit_Arel_Attributes_Attribute o - @last_column = column_for o + Thread.current[:arel_visitors_to_sql_last_column] = column_for o join_name = o.relation.table_alias || o.relation.name "#{quote_table_name join_name}.#{quote_column_name o.name}" end @@ -374,7 +373,7 @@ key on UpdateManager using UpdateManager#key= alias :visit_Bignum :literal alias :visit_Fixnum :literal - def quoted o; quote(o, @last_column) end + def quoted o; quote(o, Thread.current[:arel_visitors_to_sql_last_column]) end alias :visit_ActiveSupport_Multibyte_Chars :quoted alias :visit_ActiveSupport_StringInquirer :quoted -- cgit v1.2.3