server/routers/dry-wash/model/master.js

@@ -11,6 +11,9 @@ const schema = new Schema({
 schema.set('toJSON', {
     virtuals: true,
     versionKey: false,
+    transform(_doc, ret) {
+        delete ret._id;
+    }
 })
 
 schema.virtual('id').get(function () {