Merge pull request soundcloud#11 from Shopify/test_for_detroying_sing…

…le_row_when_the_id_is_not_1_sc_master

Test for detroying single row when the id is not 1 sc master

CHANGELOG.md

@@ -5,6 +5,7 @@
 Lhm.change_table :users, throttler: [:time_throttler, {stride: x}] do
 end
 ```
+* #118 - Truncate long trigger names. (@sj26)
 * #114 - Update chunker requirements (@bjk-soundcloud)
 * #98 - Add slave lag throttler. (@camilo, @jasonhl)
 * #92 - Fix check for table requirement before starting a lhm.(@hannestyden)

lib/lhm/chunker.rb

@@ -27,7 +27,7 @@ def initialize(migration, connection = nil, options = {})
     def execute
       return unless @start && @limit
       @next_to_insert = @start
-      while @next_to_insert < @limit || (@next_to_insert == 1 && @start == 1)
+      while @next_to_insert < @limit || (@start == @limit)
         stride = @throttler.stride
         affected_rows = @connection.update(copy(bottom, top(stride)))
 
@@ -37,6 +37,7 @@ def execute
 
         @printer.notify(bottom, @limit)
         @next_to_insert = top(stride) + 1
+        break if @start == @limit
       end
       @printer.end
     end

lib/lhm/entangler.rb

@@ -64,7 +64,7 @@ def create_delete_trigger
     end
 
     def trigger(type)
-      "lhmt_#{ type }_#{ @origin.name }"
+      "lhmt_#{ type }_#{ @origin.name }"[0...64]
     end
 
     def validate

spec/integration/chunker_spec.rb

@@ -17,7 +17,22 @@
       @migration = Lhm::Migration.new(@origin, @destination)
     end
 
-    it 'should copy 23 rows from origin to destination with time based throttler' do
+    it 'should copy 1  rows from origin to destination even if the id of the single row does not start at 1' do
+      execute("insert into origin set id = 1001 ")
+      printer = Lhm::Printer::Base.new
+
+      def printer.notify(*) ;end
+      def printer.end(*) [] ;end
+
+      Lhm::Chunker.new(@migration, connection, {:throttler => Lhm::Throttler::Time.new(:stride => 100), :printer => printer} ).run
+
+      slave do
+        count_all(@destination.name).must_equal(1)
+      end
+
+    end
+
+    it 'should copy 23 rows from origin to destination' do
       23.times { |n| execute("insert into origin set id = '#{ n * n + 23 }'") }
 
       printer = MiniTest::Mock.new

spec/unit/entangler_spec.rb

@@ -58,6 +58,21 @@
 
       @entangler.entangle.must_include strip(ddl)
     end
+
+    describe 'super long table names' do
+      before(:each) do
+        @origin = Lhm::Table.new('a' * 64)
+        @destination = Lhm::Table.new('b' * 64)
+        @migration = Lhm::Migration.new(@origin, @destination)
+        @entangler = Lhm::Entangler.new(@migration)
+      end
+
+      it 'should use truncated names' do
+        @entangler.trigger(:ins).length.must_be :<=, 64
+        @entangler.trigger(:upd).length.must_be :<=, 64
+        @entangler.trigger(:del).length.must_be :<=, 64
+      end
+    end
   end
 
   describe 'removal' do