feat: concurrent migration for postgres db

Author: serdarozerr

db/migrations/20260318083940_add_unique_constraint_to_buildpacks.rb

@@ -1,4 +1,5 @@
 Sequel.migration do
+  no_transaction # required for concurrently option on postgres
   up do
     transaction do
       # Remove duplicate entries if they exist
@@ -17,9 +18,23 @@
 
         self[:buildpacks].where(id: ids_to_remove).delete
       end
+    end
 
+    if database_type == :postgres
+      VCAP::Migration.with_concurrent_timeout(self) do
+        drop_index :buildpacks, nil,
+                   name: :unique_name_and_stack,
+                   concurrently: true,
+                   if_exists: true
+        add_index :buildpacks, %i[name stack lifecycle],
+                  name: :buildpacks_name_stack_lifecycle_index,
+                  unique: true,
+                  concurrently: true,
+                  if_not_exists: true
+      end
+    else
       alter_table(:buildpacks) do
-        # rubocop:disable Sequel/ConcurrentIndex
+        # rubocop:disable Sequel/ConcurrentIndex -- MySQL does not support concurrent index operations
         drop_index %i[name stack], name: :unique_name_and_stack if @db.indexes(:buildpacks).key?(:unique_name_and_stack)
         unless @db.indexes(:buildpacks).key?(:buildpacks_name_stack_lifecycle_index)
           add_index %i[name stack lifecycle], unique: true,
@@ -31,11 +46,25 @@
   end
 
   down do
-    alter_table(:buildpacks) do
-      # rubocop:disable Sequel/ConcurrentIndex
-      drop_index %i[name stack lifecycle], name: :buildpacks_name_stack_lifecycle_index if @db.indexes(:buildpacks).key?(:buildpacks_name_stack_lifecycle_index)
-      add_index %i[name stack], unique: true, name: :unique_name_and_stack unless @db.indexes(:buildpacks).key?(:unique_name_and_stack)
-      # rubocop:enable Sequel/ConcurrentIndex
+    if database_type == :postgres
+      VCAP::Migration.with_concurrent_timeout(self) do
+        drop_index :buildpacks, nil,
+                   name: :buildpacks_name_stack_lifecycle_index,
+                   concurrently: true,
+                   if_exists: true
+        add_index :buildpacks, %i[name stack],
+                  name: :unique_name_and_stack,
+                  unique: true,
+                  concurrently: true,
+                  if_not_exists: true
+      end
+    else
+      alter_table(:buildpacks) do
+        # rubocop:disable Sequel/ConcurrentIndex -- MySQL does not support concurrent index operations
+        drop_index %i[name stack lifecycle], name: :buildpacks_name_stack_lifecycle_index if @db.indexes(:buildpacks).key?(:buildpacks_name_stack_lifecycle_index)
+        add_index %i[name stack], unique: true, name: :unique_name_and_stack unless @db.indexes(:buildpacks).key?(:unique_name_and_stack)
+        # rubocop:enable Sequel/ConcurrentIndex
+      end
     end
   end
 end

spec/unit/models/runtime/buildpack_spec.rb

@@ -81,7 +81,7 @@ def ordered_buildpacks
       context 'when unique constraint violation is occures' do
         let(:stack) { Stack.make }
 
-        it 'raise validation error when name, stack and lifecyle is same' do
+        it 'raises validation error when name, stack and lifecyle is same' do
           Buildpack.create(name: 'oscar', stack: stack.name, lifecycle: 'cnb')
           expect do
             Buildpack.create(name: 'oscar', stack: stack.name, lifecycle: 'cnb')
@@ -90,7 +90,7 @@ def ordered_buildpacks
           end
         end
 
-        it 'raise validation error different than the unique name, stack and lifecyle' do
+        it 'raises validation error different than the unique name, stack and lifecyle' do
           existing = Buildpack.create(name: 'oscar', stack: stack.name, lifecycle: 'cnb')
           duplicate_guid = Buildpack.new(name: 'other', stack: stack.name, lifecycle: 'cnb')
           duplicate_guid.guid = existing.guid