It's worth pausing to reflect on how similar our Mongoose model schema configuration, and our model schema inside a client application like our Angular application, are to one another:

• Mongoose Post Schema:

  var postSchema = new Schema({
    title:  String,
    content: String,
    published: { type: Date, default: Date.now }
  });

• Angular Post Schema:

   export class BlogPost {
     constructor(
       public title: string = "",
       public content: string = "",
       public published: Date = new Date(),
     ) {}
   }

You may be wondering if there is some logical way to simplify our application to create our model schema once, and simply load it into both places, considering they are both JSON representations of the same object. If a model was simply a collection of properties and types, this sort of approach would be trivial. However, due to the complexity of converting default values, validation, and virtuals from one format to another, this approach is quite complicated.