From e83af52814d0b2f262e39e28bf3bc825142d0507 Mon Sep 17 00:00:00 2001
From: Chris Andreae <chris@bibo.com.ph>
Date: Mon, 8 Jul 2024 12:32:29 +0900
Subject: [PATCH] Add support for batch deletion

The VM::AR controller destroy action now optionally parses multiple ids for
deletion, and the action is aliased as a collection route as well as a member
route.

Deletion is performed one at a time within the same transaction.
---
 lib/iknow_view_models/version.rb              |  2 +-
 lib/view_model/active_record/controller.rb    | 31 +++++++++++++++++--
 .../active_record/controller_base.rb          |  2 ++
 .../active_record/controller_test.rb          | 16 ++++++++++
 4 files changed, 47 insertions(+), 4 deletions(-)

diff --git a/lib/iknow_view_models/version.rb b/lib/iknow_view_models/version.rb
index 2186409c..3c738c80 100644
--- a/lib/iknow_view_models/version.rb
+++ b/lib/iknow_view_models/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module IknowViewModels
-  VERSION = '3.10.1'
+  VERSION = '3.11.0'
 end
diff --git a/lib/view_model/active_record/controller.rb b/lib/view_model/active_record/controller.rb
index f2c5a1c7..bfd62caa 100644
--- a/lib/view_model/active_record/controller.rb
+++ b/lib/view_model/active_record/controller.rb
@@ -56,9 +56,14 @@ def create(serialize_context: new_serialize_context, deserialize_context: new_de
   end
 
   def destroy(serialize_context: new_serialize_context, deserialize_context: new_deserialize_context)
+    viewmodel_ids = parse_param(
+      :id, with: IknowParams::Serializer::ArrayOf.new(ViewmodelIdSerializer, allow_singleton: true))
+
     viewmodel_class.transaction do
-      view = viewmodel_class.find(viewmodel_id, eager_include: false)
-      view.destroy!(deserialize_context: deserialize_context)
+      views = viewmodel_class.find(viewmodel_ids, eager_include: false)
+      views.each do |view|
+        view.destroy!(deserialize_context: deserialize_context)
+      end
     end
     render_viewmodel(nil)
   end
@@ -91,8 +96,28 @@ def prerender_viewmodel(...)
 
   private
 
+  # Viewmodel ids are permitted to be either integers or strings
+  class ViewmodelIdSerializer < IknowParams::Serializer
+    def initialize
+      super(::Object)
+    end
+
+    def load(val)
+      case val
+      when ::Integer, ::String
+        val
+      else
+        raise IknowParams::Serializer::LoadError.new(
+                "Incorrect type for #{self.class.name}: #{val.inspect}:#{val.class.name}")
+      end
+    end
+
+    set_singleton!
+    json_value!
+  end
+
   def viewmodel_id
-    parse_param(:id)
+    parse_param(:id, with: ViewmodelIdSerializer)
   end
 
   def migrated_deep_schema_version
diff --git a/lib/view_model/active_record/controller_base.rb b/lib/view_model/active_record/controller_base.rb
index 9ff788ee..3c36d26e 100644
--- a/lib/view_model/active_record/controller_base.rb
+++ b/lib/view_model/active_record/controller_base.rb
@@ -156,11 +156,13 @@ def arvm_resources(resource_name, options = {}, &block)
                   name_route = { as: '' } # Only one route may take the name
                   post('', action: :create, **name_route.extract!(:as)) unless except.include?(:create) || !add_shallow_routes
                   get('',  action: :index,  **name_route.extract!(:as)) unless except.include?(:index)  || !add_shallow_routes
+                  delete('', action: :destroy, as: :bulk_delete) unless except.include?(:destroy) || !add_shallow_routes
                 end
               end
             else
               collection do
                 get('', action: :index, as: '') unless except.include?(:index)
+                delete('', action: :destroy, as: :bulk_delete) unless except.include?(:destroy)
               end
             end
           end
diff --git a/test/unit/view_model/active_record/controller_test.rb b/test/unit/view_model/active_record/controller_test.rb
index 7d00ddc9..9a4ef88d 100644
--- a/test/unit/view_model/active_record/controller_test.rb
+++ b/test/unit/view_model/active_record/controller_test.rb
@@ -167,6 +167,22 @@ def test_update
   end
 
   def test_destroy
+    other_parent = make_parent
+    parentcontroller = ParentController.new(params: { id: [@parent.id, other_parent.id] })
+    parentcontroller.invoke(:destroy)
+
+    assert_equal(200, parentcontroller.status)
+
+    assert(Parent.where(id: @parent.id).blank?, "record doesn't exist after delete")
+    assert(Parent.where(id: other_parent.id).blank?, "record doesn't exist after delete")
+
+    assert_equal({ 'data' => nil },
+                 parentcontroller.hash_response)
+
+    assert_all_hooks_nested_inside_parent_hook(parentcontroller.hook_trace)
+  end
+
+  def test_batch_destroy
     parentcontroller = ParentController.new(params: { id: @parent.id })
     parentcontroller.invoke(:destroy)