@codelytv/primitives-type

🧩 TypeScript Primitives type

TypeScript utility type in order to ensure to return only properties (not methods) containing values in primitive types such as number or boolean (not Value Objects).

Take a look, play and have fun with this. Stars are welcome 😊

👀 Usage example

You can have a domain entity such as the following Course:

import { CourseId } from "./CourseId";
import { CourseTitle } from "./CourseTitle";

export class Course {
  constructor(public courseId: CourseId, public courseTitle: CourseTitle) {}

  updateTitle(newCourseTitle: CourseTitle): void {
    this.courseTitle = newCourseTitle;
  }

  someOtherMethodWithDomainLogic(): void {
    // some algorithm
  }
}

When we want to have a toPrimitives method in order to pass an instance of the Course class between architectural layers, so the thing we want pass around should be to serialized/marshalled in a way that only containings primitive values such as:

{
  "courseId": "25658f31-2da1-4942-8b58-88aeacc79860",
  "courseTitle": "🚜 TypeScript Avanzado: Más allá de any"
}

That is:

• We want to avoid including methods such as the thisFunctionShouldNotBeIncludedInTheToPrimitives one, so the transformation should only include properties.
• We want to flatten or unwrap encapsulated properties such as the courseId and courseTitle ones. They are modelled as Value Objects (CourseId and CourseTitle classes), so the transformation or flatten should only include properties in a recursive manner.

That is exactly what our Primitives<T> utility type guarantees. Let's add it! 💪

import { Primitives } from "@codelytv/primitives-type";

import { CourseId } from "./CourseId";
import { CourseTitle } from "./CourseTitle";

export class Course {
  constructor(public courseId: CourseId, public courseTitle: CourseTitle) {}

  updateTitle(newCourseTitle: CourseTitle): void {
    this.courseTitle = newCourseTitle;
  }

  someOtherMethodWithDomainLogic(): void {
    // some algorithm
  }

  toPrimitives(): Primitives<Course> {
    return {
      courseId: this.courseId.value,
      courseTitle: this.courseTitle.value,
    };
  }
}

Done! ✌️

The Primitives<Course> return type is ensuring all our restrictions in a very straightforward way! 🌈

👍 How to install

• Npm: npm install --save-dev @codelytv/primitives-type
• Yarn: yarn add -D @codelytv/primitives-type

👌 Codely Code Quality Standards

Publishing this package we are committing ourselves to the following code quality standards:

• 🤝 Respect Semantic Versioning: No breaking changes in patch or minor versions
• 🤏 No surprises in transitive dependencies: Use the bare minimum dependencies needed to meet the purpose
• 🎯 One specific purpose to meet without having to carry a bunch of unnecessary other utilities
• ✅ Tests as documentation and usage examples
• 📖 Well documented ReadMe showing how to install and use
• ⚖️ License favoring Open Source and collaboration

🔀 Related utilities and resources

☝️ Learning resources

• 🚜 TypeScript Avanzado: Más allá de any (Spanish - Course)
• 📂 DDD en TypeScript: Estructura de carpetas (Spanish - YouTube video)
• 🔖 Domain-Driven Design en TypeScript (Spanish - Course)
• 🐥 JavaScript moderno: Buenas prácticas para empezar y refactorizar aplicaciones (Spanish - Course)
• 🏗️ De JavaScript a TypeScript (Spanish - Course)

🔷 TypeScript skeletons

• 🌱 TypeScript Basic Skeleton: Bootstrap your new TypeScript frontend project
• 🌍 TypeScript API Skeleton: Bootstrap your new TypeScript backend project

🌈 TypeScript Domain-Driven Design repositories

• ✨ TypeScript DDD Skeleton: Bootstrap your new TypeScript projects applying Hexagonal Architecture and Domain-Driven Design patterns
• 🔖 TypeScript DDD Course: Learn Domain-Driven Design in TS lesson by lesson
• 🎯 TypeScript DDD Example: Complete project applying Hexagonal Architecture and Domain-Driven Design patterns

🎯 Other languages Domain-Driven Design repositories

• ☕🎯 Java DDD Example
• 🐘🎯 PHP DDD Example
• λ🎯 Scala DDD Example
• 🦈✨ C# DDD Skeleton