enhancement(search): implement engine restore

services/search/pkg/opensearch/engine.go

@@ -61,6 +61,15 @@ func (e *Engine) Delete(id string) error {
 }
 
 func (e *Engine) Restore(id string) error {
+	_, err := e.client.Update(context.Background(), opensearchgoAPI.UpdateReq{
+		Index:      e.index,
+		DocumentID: id,
+		Body:       bytes.NewReader([]byte(`{"doc": {"Deleted": false}}`)),
+	})
+	if err != nil {
+		return fmt.Errorf("failed to mark document as deleted: %w", err)
+	}
+
 	return nil
 }
 

services/search/pkg/opensearch/engine_test.go

@@ -57,7 +57,33 @@ func TestEngine_Delete(t *testing.T) {
 	})
 }
 
-func TestEngine_Restore(t *testing.T) {}
+func TestEngine_Restore(t *testing.T) {
+	index := "test-engine-delete"
+	tc := ostest.NewDefaultTestClient(t)
+	tc.Require.IndicesReset([]string{index})
+	tc.Require.IndicesCount([]string{index}, "", 0)
+
+	defer tc.Require.IndicesDelete([]string{index})
+
+	engine, err := opensearch.NewEngine(index, tc.Client())
+	assert.NoError(t, err)
+
+	t.Run("mark document as not deleted", func(t *testing.T) {
+		document := ostest.Testdata.Resources.Full
+		document.Deleted = true
+		tc.Require.DocumentCreate(index, document.ID, toJSON(t, document))
+		tc.Require.IndicesCount([]string{index}, "", 1)
+
+		tc.Require.IndicesCount([]string{index}, opensearch.NewRootQuery(
+			opensearch.NewTermQuery[bool]("Deleted").Value(true),
+		).String(), 1)
+
+		assert.NoError(t, engine.Restore(document.ID))
+		tc.Require.IndicesCount([]string{index}, opensearch.NewRootQuery(
+			opensearch.NewTermQuery[bool]("Deleted").Value(true),
+		).String(), 0)
+	})
+}
 
 func TestEngine_Purge(t *testing.T) {
 	index := "test-engine-purge"