lib/lhm/entangler.rb in lhm-1.0.0.rc2 vs lib/lhm/entangler.rb in lhm-1.0.0.rc3

@@ -1,33 +1,32 @@
-#
-#  Copyright (c) 2011, SoundCloud Ltd., Rany Keddo, Tobias Bielohlawek, Tobias
-#  Schmidt
-#
-#  Creates entanglement between two tables. All creates, updates and deletes
-#  to origin will be repeated on the the destination table.
-#
+# Copyright (c) 2011, SoundCloud Ltd., Rany Keddo, Tobias Bielohlawek, Tobias
+# Schmidt
 
 require 'lhm/command'
+require 'lhm/sql_helper'
 
 module Lhm
   class Entangler
     include Command
+    include SqlHelper
 
-    attr_reader :epoch
+    attr_reader :connection
 
+    # Creates entanglement between two tables. All creates, updates and deletes
+    # to origin will be repeated on the destination table.
     def initialize(migration, connection = nil)
       @common = migration.intersection
       @origin = migration.origin
       @destination = migration.destination
       @connection = connection
     end
 
     def entangle
       [
-        create_trigger_del,
-        create_trigger_ins,
-        create_trigger_upd
+        create_delete_trigger,
+        create_insert_trigger,
+        create_update_trigger
       ]
     end
 
     def untangle
       [
@@ -35,29 +34,29 @@
         "drop trigger if exists `#{ trigger(:ins) }`",
         "drop trigger if exists `#{ trigger(:upd) }`"
       ]
     end
 
-    def create_trigger_ins
+    def create_insert_trigger
       strip %Q{
         create trigger `#{ trigger(:ins) }`
         after insert on `#{ @origin.name }` for each row
         replace into `#{ @destination.name }` (#{ @common.joined })
         values (#{ @common.typed("NEW") })
       }
     end
 
-    def create_trigger_upd
+    def create_update_trigger
       strip %Q{
         create trigger `#{ trigger(:upd) }`
         after update on `#{ @origin.name }` for each row
         replace into `#{ @destination.name }` (#{ @common.joined })
         values (#{ @common.typed("NEW") })
       }
     end
 
-    def create_trigger_del
+    def create_delete_trigger
       strip %Q{
         create trigger `#{ trigger(:del) }`
         after delete on `#{ @origin.name }` for each row
         delete ignore from `#{ @destination.name }`
         where `#{ @destination.name }`.`id` = OLD.`id`
@@ -66,14 +65,10 @@
 
     def trigger(type)
       "lhmt_#{ type }_#{ @origin.name }"
     end
 
-    #
-    # Command implementation
-    #
-
     def validate
       unless table?(@origin.name)
         error("#{ @origin.name } does not exist")
       end
 
@@ -82,11 +77,10 @@
       end
     end
 
     def before
       sql(entangle)
-      @epoch = connection.select_value("select max(id) from #{ @origin.name }").to_i
     end
 
     def after
       sql(untangle)
     end
@@ -100,6 +94,5 @@
     def strip(sql)
       sql.strip.gsub(/\n */, "\n")
     end
   end
 end
-