Snapshots revert API

app/controllers/api/base_controller/parser.rb

@@ -291,7 +291,7 @@ def validate_post_api_action_as_subcollection(cname, mname, aname)
         return if cname == @req.collection
         return if collection_config.subcollection_denied?(@req.collection, cname)
 
-        aspec = collection_config.typed_subcollection_actions(@req.collection, cname)
+        aspec = collection_config.typed_subcollection_actions(@req.collection, cname, @req.s_id ? :subresource : :subcollection)
         return unless aspec
 
         action_hash = fetch_action_hash(aspec, mname, aname)

app/controllers/api/subcollections/snapshots.rb

@@ -34,6 +34,17 @@ def delete_resource_snapshots(parent, type, id, _data)
       end
       alias snapshots_delete_resource delete_resource_snapshots
 
+      def snapshots_revert_resource(parent, type, id, _data)
+        raise parent.unsupported_reason(:revert_to_snapshot) unless parent.supports_revert_to_snapshot?
+        snapshot = resource_search(id, type, collection_class(type))
+
+        message = "Reverting to snapshot #{snapshot.name} for #{snapshot_ident(parent)}"
+        task_id = queue_object_action(parent, message, :method_name => "revert_to_snapshot", :args => [id])
+        action_result(true, message, :task_id => task_id)
+      rescue => e
+        action_result(false, e.to_s)
+      end
+
       private
 
       def snapshot_ident(parent)

config/api.yml

@@ -2262,6 +2262,8 @@
       - :name: read
         :identifier: vm_snapshot_view
       :post:
+      - :name: revert
+        :identifier: vm_snapshot_revert
       - :name: delete
         :identifier: vm_snapshot_delete
       :delete:

spec/requests/api/snapshots_spec.rb

@@ -133,6 +133,52 @@
       end
     end
 
+    describe "POST /api/vms/:c_id/snapshots/:s_id with revert action" do
+      it "can queue a VM for reverting to a snapshot" do
+        api_basic_authorize(action_identifier(:vms, :revert, :snapshots_subresource_actions))
+        ems = FactoryGirl.create(:ext_management_system)
+        host = FactoryGirl.create(:host, :ext_management_system => ems)
+        vm = FactoryGirl.create(:vm_vmware, :name => "Alice's VM", :host => host, :ext_management_system => ems)
+        snapshot = FactoryGirl.create(:snapshot, :name => "Alice's snapshot", :vm_or_template => vm)
+
+        run_post("#{vms_url(vm.id)}/snapshots/#{snapshot.id}", :action => "revert")
+
+        expected = {
+          "message"   => "Reverting to snapshot Alice's snapshot for Virtual Machine id:#{vm.id} name:'Alice's VM'",
+          "success"   => true,
+          "task_href" => a_string_matching(tasks_url),
+          "task_id"   => anything
+        }
+        expect(response.parsed_body).to include(expected)
+        expect(response).to have_http_status(:ok)
+      end
+
+      it "renders a failed action response if reverting is not supported" do
+        api_basic_authorize(action_identifier(:vms, :revert, :snapshots_subresource_actions))
+        vm = FactoryGirl.create(:vm_vmware)
+        snapshot = FactoryGirl.create(:snapshot, :vm_or_template => vm)
+
+        run_post("#{vms_url(vm.id)}/snapshots/#{snapshot.id}", :action => "revert")
+
+        expected = {
+          "success" => false,
+          "message" => "The VM is not connected to a Host"
+        }
+        expect(response.parsed_body).to include(expected)
+        expect(response).to have_http_status(:ok)
+      end
+
+      it "will not revert to a snapshot unless authorized" do
+        api_basic_authorize
+        vm = FactoryGirl.create(:vm_vmware)
+        snapshot = FactoryGirl.create(:snapshot, :vm_or_template => vm)
+
+        run_post("#{vms_url(vm.id)}/snapshots/#{snapshot.id}", :action => "revert")
+
+        expect(response).to have_http_status(:forbidden)
+      end
+    end
+
     describe "POST /api/vms/:c_id/snapshots/:s_id with delete action" do
       it "can queue a snapshot for deletion" do
         api_basic_authorize(action_identifier(:vms, :delete, :snapshots_subresource_actions, :delete))