Course Introduction

Project Architecture

Introduction

The Concept of Signals

The importance of Signals over Change Detection and Zone.js

How to Create a Signal

Reactive Primitives in Signals

 Getting Started with Signals

Module 3 Introduction

Fetching Data from the Server using RxJS

Using the Interoperability API to convert Http requests to Signals

Signals and Http Requests

Module 4 Introduction

Adding Items to the Shopping Cart

Integrate Counter Functionality and Remove Items from Cart

Implement the Checkout Page

Exercise

Error Handling in Signals

Sharing Data Between Different Components with Signals

Wrapping up the Course

Course Wrap Up

### How The Course Works:

- The "Build a Modern Web Application using Angular Signals" course is a comprehensive online program spanning five modules. Discover how to effectively utilize Signals to manage the entire state of an Angular application, integrate the newly built-in control flows, employ deferrable views, navigate components using lazy loaded routes, and implement Standalone components.
- Remote Access: Take advantage of the course from any location, allowing you the flexibility to engage with the materials at your convenience.
- Self-Paced Learning: Tailor your learning experience to your schedule, enabling you to progress through the course content at your own pace.
- Community Engagement: Collaborate and learn alongside a diverse community of fellow students, fostering an environment of shared knowledge and support.
- Structured Learning: Experience a well-organized curriculum designed to provide a cohesive and comprehensive understanding of Angular Signals in a logical progression.

### Understanding the Challenges

Learning Angular 17 can present various hurdles and frustrations for those new to the technology. As individuals navigate their journey into this advanced framework, they commonly encounter several challenges:

- Complexity Barrier: The intricate architecture and extensive feature set of Angular 17 can overwhelm newcomers, posing a significant learning curve.
- State Management Complexity: Managing the state of an Angular application efficiently, especially with the nuances of Signals, can prove challenging for learners.
- Integration Puzzles: Integrating and harnessing newly built-in control flows, deferrable views, Standalone components, and lazy loaded routes can be intricate and perplexing.
- Navigational Complexity: Understanding the intricacies of lazy loaded routes and effective navigation between components can pose obstacles to a smooth learning experience.

Navigating through these complexities without guidance can hinder the progress of aspiring developers aiming to master Angular 17.


### Advantages of Learning Angular 17 in 2023

- Enhanced Performance: In 2023, Angular 17 offers optimized performance enhancements, enabling you to craft high-performing web applications capable of meeting modern user expectations.
- Cutting-Edge Features: Stay ahead in the web development landscape by mastering the latest built-in control flows, deferrable views, and other advanced functionalities unique to Angular 17.
- Industry Relevance: With Angular continuing to be a sought-after framework in the industry, mastering Angular 17 ensures you remain competitive and relevant in the job market.
- Improved Developer Experience: Angular 17 introduces refinements and enhancements that streamline the development process, providing a more efficient and enjoyable experience for developers.
- Scalability and Maintainability: Learning Angular 17 equips you with the knowledge to build scalable and maintainable applications, crucial factors in modern software development.

### Why Learn Angular 17 in 2023

Angular 17 stands at the forefront of web development frameworks in the current year, offering you several compelling reasons to dive into its intricacies:
Embrace the evolution of web development by mastering Angular 17 in 2023. This advanced version presents you with enhanced performance capabilities, cutting-edge features, and improved developer experiences. Remaining proficient in Angular ensures your relevance in a competitive industry, equipping you with the skills necessary to build scalable, high-performing applications that meet the demands of modern users.

### Course Content Overview

Course Overview:
Total Modules: **5**
Total Lessons: **12**
Total Video Runtime: **1 hour, 41 minutes**

### Summary:
This course is structured into five comprehensive modules, guiding you through the intricacies of Angular 17 Signals. From laying the groundwork with introductory concepts to diving deep into handling HTTP requests, sharing data between components, and culminating with a thorough review in the conclusion module, each section builds upon the last, empowering you to master Angular 17 Signals effectively.

Learn how to surgically manage state and optimize UI rendering with Angular Signals. This course introduces students to the world of Angular Signals, from reactive primitives to seamless interoperability between observables and signals. By the end of this course, you'll have learned how to build a highly performant, lightweight Angular application that features deferrable views, lazy loaded routes, and a PayPal-powered checkout flow. Additionally, you'll have learned the techniques needed to modernize older Angular applications so that they're able to fully leverage the power of Angular Signals.

Demystifying Reactivity with Angular Signals

Fetch data from a REST API making use of Signals.

Make use signals to add functionalities to the shopping cart

Checkout selected items from the cart using the available Signal APIs

How to manage state in an Angular application by making use of Signals

The importance of using Signals to enhance change detection

How to integrate a robust lazy loading approach, by making use of deferrable views and lazy loaded routes

Difference between using RxJS and Signals when working with data and asynchronous operations

How to structure an Angular application using Standalone components

How to work with the newly built-in control flows

Converting Observables to Signals with Angular's Interoperability API

In the previous lesson, we discussed how to fetch data from a REST API using observables. As we continue our journey of learning, this article will build on that foundation by teaching how to convert these observables to signals. The conversion is achieved using the interoperability API's toSignal method in Angular. This process enhances the performance and reactivity of code, simplifying the process of consuming REST APIs in components.

Here's the application we'll be working with:

 API is made available through the interoperability API in Angular. By converting observables to signals, we can better manage data streams, leading to more efficient and responsive applications.

 API can accept a generic type, different data types, and a source—data aimed to be fetched from the REST API. Additionally, it can accept an initial value, which if not provided, defaults to 'undefined'.

import { toSignal } from '@angular/interoperability';

let observable = fetchData('https://my-api.com/data'); //fetchData is a hypothetical function that fetches data from a REST API
let signal = toSignal(observable, []);

---
title: Using the Interoperability API to convert Http requests to Signals
description: Here we get to modify the code we wrote previously to fetch data from the server. We go ahead to show the simplicity of Signals by converting the data gotten from the Observable into Signals making use of the Interoperability API.
code: https://gitlab.com/fullstackio/books/newline-course-apps/fundamentals-of-signals-in-angular-app/-/tree/main/module_3_lesson_3?ref_type=heads
privateVideoUrl: https://stream.mux.com/LS014vbi2w2XCm7yvWH202Gx1wNtayKGnwr6R7JVz2xWk.m3u8
isPublicLesson: true
useMdx: true
---

# Converting Observables to Signals with Angular's Interoperability API

## Introduction

In the previous lesson, we discussed how to fetch data from a REST API using observables. As we continue our journey of learning, this article will build on that foundation by teaching how to convert these observables to signals. The conversion is achieved using the interoperability API's toSignal method in Angular. This process enhances the performance and reactivity of code, simplifying the process of consuming REST APIs in components.

Here's the application we'll be working with:

<ReplitEmbed src="https://replit.com/@newlineauthors/angularappmodule3lesson3" />

## Understanding toSignal API

The `toSignal` API is made available through the interoperability API in Angular. By converting observables to signals, we can better manage data streams, leading to more efficient and responsive applications.

The `toSignal` API can accept a generic type, different data types, and a source—data aimed to be fetched from the REST API. Additionally, it can accept an initial value, which if not provided, defaults to 'undefined'.

Here's a basic example of how the `toSignal` API can be utilized:

Here we get to modify the code we wrote previously to fetch data from the server. We go ahead to show the simplicity of Signals by converting the data gotten from the Observable into Signals making use of the Interoperability API.

Learn

The newline Guide to Building Your First GraphQL Server with Node and TypeScript

Teach

Amelia Wattenberger

Author of Fullstack D3

Community

Demystifying Reactivity with Angular Signals

WELCOMEIntroduction

Introduction:

Start Here

Module 1: Introduction

Lesson 1: (4:44)

Course Introduction

Lesson 2: (8:57)

Project Architecture

Module 2: Getting Started with Signals

Lesson 1: (8:22)

The Concept of Signals

Lesson 2: (2:13)

The importance of Signals over Change Detection and Zone.js

Lesson 3: (3:32)

How to Create a Signal

Lesson 4: (12:35)

Reactive Primitives in Signals

Module 3: Signals and Http Requests

Lesson 1: (0:42)

Module 3 Introduction

Lesson 2: (9:43)

Fetching Data from the Server using RxJS

Lesson 3: (6:09)

Using the Interoperability API to convert Http requests to Signals

Module 4: Sharing Data Between Different Components with Signals

Lesson 1: (0:40)

Module 4 Introduction

Lesson 2: (7:10)

Adding Items to the Shopping Cart

Lesson 3: (14:50)

Integrate Counter Functionality and Remove Items from Cart

Lesson 4: (15:42)

Implement the Checkout Page

Lesson 5: (1:52)

Exercise

Lesson 6: (4:34)

Error Handling in Signals

Module 5: Course Wrap Up

Lesson 1: (2:14)

Wrapping up the Course

Using the Interoperability API to convert Http requests to Signals