set vm ancestry from relationship resource info

db/migrate/20200607025146_add_ancestry_to_vm.rb

@@ -0,0 +1,61 @@
+class AddAncestryToVm < ActiveRecord::Migration[5.2]
+  class VmOrTemplate < ActiveRecord::Base
+    self.inheritance_column = :_type_disabled
+    self.table_name = 'vms'
+    has_many :all_relationships, :class_name => "AddAncestryToVm::Relationship", :dependent => :destroy, :as => :resource
+  end
+
+  class Vm < VmOrTemplate
+  end
+
+  class Relationship < ActiveRecord::Base
+    belongs_to :vm, :class_name => 'AddAncestryToVm::VmOrTemplate', :foreign_key => :vm_id
+  end
+
+  def up
+    add_column :vms, :ancestry, :string
+    add_index :vms, :ancestry
+
+    say_with_time("set vm ancestry from existing genealogy relationship resource information") do
+      connection.execute <<-SQL
+      UPDATE vms
+      SET ancestry = new_ancestry
+      FROM (
+        SELECT ancestor_resources_for_vms.vm_id AS vm_id,
+        ARRAY_TO_STRING(ARRAY_AGG(res_rels.resource_id)::VARCHAR[], '/') AS new_ancestry
+        FROM (
+          SELECT vms.id AS vm_id, relationships.id AS rel_id
+          FROM vms
+          JOIN relationships a_rels ON a_rels.resource_id = vms.id
+          AND a_rels.relationship = 'genealogy'
+          AND a_rels.resource_type = 'VmOrTemplate'
+          LEFT JOIN LATERAL UNNEST(STRING_TO_ARRAY(a_rels.ancestry, '/')::BIGINT[])
+          WITH ORDINALITY AS relationships(id, indx) ON TRUE
+          ORDER BY vms.id, relationships.indx
+        ) AS ancestor_resources_for_vms
+        JOIN relationships res_rels ON res_rels.id = ancestor_resources_for_vms.rel_id AND res_rels.relationship = 'genealogy'
+        GROUP BY ancestor_resources_for_vms.vm_id
+      ) AS new_ancestors_for_vms
+      WHERE new_ancestors_for_vms.vm_id = vms.id
+      SQL
+    end
+
+    connection.execute <<-SQL
+    DELETE FROM relationships
+    WHERE relationship = 'genealogy' AND resource_type = 'VmOrTemplate'
+    AND resource_id
+    IN (SELECT vms.id FROM vms);
+    SQL
+  end
+
+  def down
+    say_with_time("create relationship records from vm ancestry") do
+      vms_with_ancestry = Vm.select { |vm| vm.ancestry.present? }
+      vms_with_ancestry.each do |vm|
+        Relationship.create!(:relationship => 'genealogy', :resource_type => 'VmOrTemplate', :resource_id => vm.id, :ancestry => vm.ancestry)
+      end
+
+      remove_column :vms, :ancestry
+    end
+  end
+end

spec/migrations/20200607025146_add_ancestry_to_vm_spec.rb

@@ -0,0 +1,138 @@
+require_migration
+
+describe AddAncestryToVm do
+  let(:rel_stub) { migration_stub(:Relationship) }
+  let(:vm_stub) { migration_stub :VmOrTemplate }
+  let(:vm) { vm_stub.create! }
+  let(:vm2) { vm_stub.create! }
+  let(:vm3) { vm_stub.create! }
+  let(:vm4) { vm_stub.create! }
+  let(:vm5) { vm_stub.create! }
+  let(:vm6) { vm_stub.create! }
+  let(:root) { vm_stub.create! }
+
+  migration_context :up do
+    context "single parent/child rel" do
+      it 'updates ancestry' do
+        parent_rel = rel_stub.create!(:relationship => 'genealogy', :ancestry => nil, :resource_type => 'VmOrTemplate', :resource_id => root.id)
+        rel_stub.create!(:relationship => 'genealogy', :ancestry => parent_rel.id, :resource_type => 'VmOrTemplate', :resource_id => vm.id)
+
+        migrate
+
+        expect(vm.reload.ancestry).to eq(root.id.to_s)
+        expect(root.reload.ancestry).to eq(nil)
+        expect(AddAncestryToVm::Relationship.count).to eq(0)
+      end
+    end
+
+    context "slightly more complicated tree" do
+      it 'updates ancestry' do
+        parent_rel = rel_stub.create!(:relationship => 'genealogy', :ancestry => nil, :resource_type => 'VmOrTemplate', :resource_id => root.id)
+        child_rel = rel_stub.create!(:relationship => 'genealogy', :ancestry => parent_rel.id, :resource_type => 'VmOrTemplate', :resource_id => vm.id)
+        rel_stub.create!(:relationship => 'genealogy', :ancestry => child_rel.id.to_s + '/' + parent_rel.id.to_s, :resource_type => 'VmOrTemplate', :resource_id => vm2.id)
+
+        migrate
+
+        expect(vm.reload.ancestry).to eq(root.id.to_s)
+        expect(vm2.reload.ancestry).to eq("#{vm.id}/#{root.id}")
+        expect(root.reload.ancestry).to eq(nil)
+        expect(AddAncestryToVm::Relationship.count).to eq(0)
+      end
+    end
+
+    context "complicated tree" do
+      #           a
+      #      b         c
+      #      d         g
+      #    e   f
+      it 'updates ancestry' do
+        rel_a = rel_stub.create!(:relationship => 'genealogy', :ancestry => nil, :resource_type => 'VmOrTemplate', :resource_id => root.id)
+        rel_c = rel_stub.create!(:relationship => 'genealogy', :ancestry => rel_a.id, :resource_type => 'VmOrTemplate', :resource_id => vm.id)
+        rel_stub.create!(:relationship => 'genealogy', :ancestry => rel_c.id.to_s + '/' + rel_a.id.to_s, :resource_type => 'VmOrTemplate', :resource_id => vm2.id)
+        rel_b = rel_stub.create!(:relationship => 'genealogy', :ancestry => rel_a.id.to_s, :resource_type => 'VmOrTemplate', :resource_id => vm3.id)
+        rel_d = rel_stub.create!(:relationship => 'genealogy', :ancestry => rel_b.id.to_s + '/' + rel_a.id.to_s, :resource_type => 'VmOrTemplate', :resource_id => vm4.id)
+        rel_stub.create!(:relationship => 'genealogy', :ancestry => rel_d.id.to_s + '/' + rel_b.id.to_s + '/' + rel_a.id.to_s, :resource_type => 'VmOrTemplate', :resource_id => vm5.id)
+        rel_stub.create!(:relationship => 'genealogy', :ancestry => rel_d.id.to_s + '/' + rel_b.id.to_s + '/' + rel_a.id.to_s, :resource_type => 'VmOrTemplate', :resource_id => vm6.id)
+
+        migrate
+
+        expect(vm5.reload.ancestry).to eq("#{vm4.id}/#{vm3.id}/#{root.id}")
+        expect(vm6.reload.ancestry).to eq("#{vm4.id}/#{vm3.id}/#{root.id}")
+        expect(vm3.reload.ancestry).to eq(root.id.to_s)
+        expect(vm.reload.ancestry).to eq(root.id.to_s)
+        expect(vm2.reload.ancestry).to eq("#{vm.id}/#{root.id}")
+        expect(root.reload.ancestry).to eq(nil)
+        expect(AddAncestryToVm::Relationship.count).to eq(0)
+      end
+    end
+
+    context "vm without rels" do
+      it 'nil ancestry' do
+        migrate
+
+        expect(AddAncestryToVm::Vm.find(vm.id).ancestry).to eq(nil)
+      end
+    end
+
+    context "with only ems_metadata relationship tree" do
+      it 'sets nothing' do
+        parent_rel = rel_stub.create!(:relationship => 'ems_metadata', :ancestry => nil, :resource_type => 'VmOrTemplate', :resource_id => root.id)
+        rel_stub.create!(:relationship => 'ems_metadata', :ancestry => parent_rel.id, :resource_type => 'VmOrTemplate', :resource_id => vm.id)
+
+        migrate
+
+        expect(vm.reload.ancestry).to eq(nil)
+        expect(root.reload.ancestry).to eq(nil)
+        expect(AddAncestryToVm::Relationship.count).to eq(2)
+      end
+    end
+
+    context "with both genealogy and ems_metadata rels" do
+      it 'only sets ancestry from genealogy rels' do
+        invalid_parent_rel = rel_stub.create!(:relationship => 'ems_metadata', :ancestry => nil, :resource_type => 'VmOrTemplate', :resource_id => root.id)
+        rel_stub.create!(:relationship => 'ems_metadata', :ancestry => invalid_parent_rel.id, :resource_type => 'VmOrTemplate', :resource_id => vm.id)
+        parent_rel = rel_stub.create!(:relationship => 'genealogy', :ancestry => nil, :resource_type => 'VmOrTemplate', :resource_id => root.id)
+        rel_stub.create!(:relationship => 'genealogy', :ancestry => parent_rel.id, :resource_type => 'VmOrTemplate', :resource_id => vm.id)
+
+        migrate
+
+        expect(vm.reload.ancestry).to eq(root.id.to_s)
+        expect(root.reload.ancestry).to eq(nil)
+        expect(AddAncestryToVm::Relationship.count).to eq(2)
+      end
+    end
+  end
+
+
+  migration_context :down do
+    context "multiple rels" do
+      let(:vm) { vm_stub.create!(:ancestry => '6/5/4') }
+      it 'creates rel and removes ancestry' do
+        vm
+
+        migrate
+
+        rel = AddAncestryToVm::Relationship.first
+        expect(rel.relationship).to eq('genealogy')
+        expect(rel.ancestry).to eq('6/5/4')
+        expect(rel.resource_type).to eq('VmOrTemplate')
+        expect(rel.resource_id).to eq(vm.id)
+      end
+    end
+
+    context "single rel" do
+      let(:vm) { vm_stub.create!(:ancestry => '645') }
+      it 'creates rel and removes ancestry' do
+        vm
+
+        migrate
+
+        rel = AddAncestryToVm::Relationship.first
+        expect(rel.relationship).to eq('genealogy')
+        expect(rel.ancestry).to eq('645')
+        expect(rel.resource_type).to eq('VmOrTemplate')
+        expect(rel.resource_id).to eq(vm.id)
+      end
+    end
+  end
+end