It is great news for Angular Developers that Angular has released its latest version Angular 17. The Angular 17 released on November 8, 2023. It seems like a big improvement for the framework, which started back in September 2016. Now, when we say rebirth, we don’t mean they completely changed everything from scratch. Instead, they’ve upgraded it by adding important features that take advantage of the latest browser capabilities. This makes Angular even more powerful than before. The big questions here are: Why is Angular 17 a game-changer? What makes this release stand out and be so extraordinary?
Introduction to Angular 17
The introduction of Angular 17 is not just about new releases or improvements. it’s a holistic renewal that brings forward a suite of enhancements and a fresh identity for Angular. However, the Angular team has been working hard to resolve challenges and deliver improved performance and developer experience on the modern web.
That’s what made them introduce Angular’s reactivity system, Server Side Rendering (SSR), and many other features in Angular 17. In addition, Angular 17 comes with Standalone Components and Signals as part of this movement. Angular 17 offers better Angular Renaissance as it comes with a new syntax for control flow, lazy loading of page parts, and better support for SSR.
In addition, the CLI now relies on ESBuild and thus enhances the build significantly. In the coming days, they are planning to release Angular v17, including deferred views, built-in control flow, SSR enhancements, and view transitions API support. You will soon experience it once you install Angular on your system and migrate to Angular v17.
The @Component Annotation
The @Component annotation has upgraded. Since the early days of Angular, it was necessary to use a style array or an array of relative paths to style sheets to attach styles to our components.
In simple terms, usually, a view has connected to a style sheet.
Now, there’s a new thing called styleUrl. It’s like a fresh addition. The styles property can have a single string or a bunch of strings as its value.
Let’s talk about the new feature which is application builder.
New Application Builder Introduced
Angular has always employed different tools to construct our applications, mainly catering to two types:
- Client-Side Rendering: In this approach, the entire application is built on the client side. In simpler terms, the application is created in a format known as the DOM (Document Object Model). Navigation, data fetching, and templating all happen on the client’s device instead of the server.
- Server-Side Rendering: This method involves rendering the application in HTML format. Each page of the application is initially rendered in HTML in response to navigation, and then this page is brought to life to become dynamic.
The choice of builder depends on the type of application:
- For client-side rendering, Angular has traditionally used
- For server-side rendering, it utilized
With the introduction of Angular 16, an experimental builder emerged:
@angular-devkit/build-angular:browser-esbuild. This innovative builder employed Vite for the dev-server and esbuild for the build, resulting in remarkable performance improvements:
- 87% faster application builds
- 82% faster dev-server for the application
However, the builder for server rendering remained unchanged.
Now, with the release of Angular 17, a new, versatile builder has been introduced:
@angular-devkit/build-angular:application. This builder allows for the construction of both client-side rendering and server-side rendering applications. Let’s give a round of applause for this adaptable builder!
For existing applications using the
@angular-devkit/build-angular:browser-esbuild builder, migrating to the new builder is relatively straightforward. Yet, for server-side rendering applications, migration is a bit more intricate due to the numerous properties that need adjustment.
Added New Angular Code Flow
The introduction of Angular 17 comes with a more potent flow code. In prior versions, we relied on structural directives like ngIf, ngSwitch, and ngFor to handle our page structure. While these structural directives are powerful due to the micro syntax they employ, they do have their limitations. Therefore, a new flow code has developed.
This new flow code represents an enhanced approach to managing the flow and structure of an Angular application. However, the specific syntax and details of this flow code weren’t provided in your context. To get a comprehensive understanding of this new flow code, I recommend referring to the official Angular 17 documentation or release notes, where you’ll find detailed information on its syntax and capabilities.
In the above code, the code demonstrates that there’s no requirement to import the ngIf and ngFor directives anymore. This new code flow is built into Angular. It makes it easier to integrate components based on Angular signals.
It’s important to note that structural directives have not deprecated. There are no current plans to deprecate them. However, looking ahead, only the ngIf, ngFor, and ngSwitch directives might be considered for deprecation.
If you’re interested in automatically migrating your components to the new code flow, the provided schematic will be a valuable tool for making the transition smoother.
ng g @angular/core:control-flow
Warning: The newly introduced flow code is quite recent, so you might come across formatting issues. Notably, Prettier version 3.1 now provides support for this code flow.
As for Integrated Development Environments (IDEs):
- VsCode with Angular Language Service Plugins: This already supports syntax highlighting for the new code flow.
- WebStorm EAP: Also supports syntax highlighting; however, template checking is not fully supported at the moment. Expect support for template checking shortly.
The Most Awaited Feature: Defer Added
Certainly, one of the standout features of this release is the enhanced ability to easily lazy-load components.
While it was possible to achieve lazy loading with EsModules and the *ngComponentOutlet structural directive in previous versions, this approach had its challenges. Developers needed to carefully manage the entire loading process, including considerations for loading, errors, etc. Additionally, there were limitations in scope, making tasks like prefetching more complicated. In essence, the developer experience was not as seamless.
Angular 17 released a powerful solution with the defer feature. It simplifies the process of lazy-loading components. Defer takes care of all stages of lazy loading, addressing the previous challenges and providing a more user-friendly developer experience.
In conclusion, Angular 17 introduces a transformative set of features that goes beyond typical updates. It marks a holistic renaissance for the Angular framework, enhancing its capabilities and providing a fresh identity. The Angular team has addressed challenges, focusing on improved performance and an enhanced developer experience for the modern web.