Migrating to Angular 5: 5 reasons why & 3 simple ways to do it

AngularJS is a structural framework for dynamic web apps, specifically for single-page web applications. It is a JavaScript-based web application framework that binds the HTML with the JavaScript. AngularJS is the original version of Angular MVC (Model-View-Controller) framework created by Google; Angular, in general, provides the synchronization between the Model and the View in what is known as 2-way data binding. AngularJS, even in its initial form (used only with JavaScript), was and still is a popular framework for web application development.

Angular 5 is an advanced version of AngularJS framework that supports Typescript (a syntactical superset of JavaScript) and works with multiple platforms across various media such as web, desktop and mobile applications of various types and versions. AngularJS was created in the year 2009 by Google. It was one of the effective frameworks to create dynamic web applications.

Subsequently, Angular 2 and Angular 4 were also released (3 was skipped), with more capabilities in the framework. Eventually, Angular 5 made its release in the month of November 2017. Significantly, the support of Typescript from Angular 2 onwards makes Angular framework different from its predecessor. Angular 2 supported Typescript 2.0, whereas Angular 4 supported Typescript versions 2.1 and 2.2. Although, Angular 4 is backward compatible with Typescript 2.0.

Angular 5 is the latest version and is the subject of discussion in this white paper. Overall, the Angular framework is used by millions of developers, a fact that could make the availability of skilled developers possible.

Often AngularJS is also known as Angular 1; sometimes the term Angular is used synonymously with any version of Angular. It would suffice to understand that AngularJS is the initial version of Angular (version 1.x) and supported only JavaScript.

What makes Angular 5 the most preferable framework

Source: Stackoverflow Developer Survey 2018 (Angular was declared the 2nd “Most Popular Technology”)

Angular framework (the latest release 5) was developed keeping in view the expanding horizons of the web development in order to have a common framework, particularly for dynamic web apps. There are at least five major reasons why it is worthwhile moving to Angular 5:

• Enabling cross-platform development: Angular 5 framework makes it possible to develop any web application for any purpose, whether it is for internet, mobile network, native mobile or for a native desktop application.
• Speed and Performance: The Angular 5 framework can turn templates into code that is highly optimized, thus increasing the speed of code generation. Higher speeds of deployment are achieved with the universal framework; the server side content-rendering provided by the framework for single-page applications that enables faster deployment of internet pages with optimized metadata. The component router can be used to load only that code required to render the view based on the context.
• Advanced development tool: Angular 5 provides many UI templates with appropriate syntax within the framework; it provides Command Line Interface (CLI) Tools for building, adding and deploying apps rapidly. The IDE that comes with Angular 5 could be a paradise for developers. With features such as auto-completion, instant error prompting, warnings and other feedbacks, Angular 5 packs these and many others that can enhance the coding experience and speed.
• Support for PWA: Angular 5 provides support to building Progressive Web Applications (PWA) with enhanced UI, which makes use of the latest web technologies to enhance the dynamism of the web application. Availability of this support results in advantages like High performance, app-like experience, offline functioning and zero-step installation.
• Adopted by millions: The patronage of the Angular community has been ever increasing running into millions of developers across the world of internet due to the versatility and superiority of development experience.

Angular 5 is a faster, lighter and easier to use framework that can help build numerous applications. Apart from bug fixes from the previous versions, this one has several new features such as Build Optimizer, Ahead of Time (AOT) compiler, new HTTP client, internationalized date/time/currency, watch mode compilation, Universal transfer API, and DOM support.

What is new in Angular 5?

Angular 5 is many steps ahead in terms of framework features and support compared to its predecessors:

• Typescript support: Typescript is a superset of the JavaScript that was developed by Microsoft. Typescript is designed to build large-scale and size applications and can be compiled across to JavaScript also. One of the features of the Angular framework from version 2 onwards till version 5 is the support of Typescript with a backward compatibility to JavaScript. The latest version of Typescript is 2.8; Angular 5 supports Typescript version 2.4. Successive versions of Angular supported successive versions of Typescript to provide the developers with a powerful combination of the two.
• Component-based UI: AngularJS employs the MVC model of application in which the controller is an essential part, but controller works with considerable rigidity and lesser reuse. Angular framework (from version 2 till 5) changed this to a component framework. This feature lets the programmers to segregate the applications in terms of the components required to render the required UI. This helps in improving the flexibility in the use of components and also improves their reusability compared to a controller framework. The term MVW (Model-View-Whatever) signifies the component-based framework as compared to the term MVC (Model-View-Controller) which signified controller framework.
• Mobile Support: Angular frameworks (from 2 onwards) support the mobile app development as they support the mobile development platforms like React Native. More recent versions like Angular 5 have supported strategies from Cordova, Ionic, and NativeScript.
• SEO support: Search Engine Optimization (SEO) is an essential requirement for any website of today. Locating a website for a user amongst millions of different websites or hundreds of similar websites is fulfilled by search engines like Google, which rely on the content and organization of website information. Hence, this requires organization of content on websites to be optimized with appropriate keywords, flow of content and metadata. Single Page Applications made possible by Angular framework can be particularly challenging from SEO point of view, as the content could be dynamic. Websites developed using Angular framework (like version 5) render HTML at the server side which makes it possible to engineer the presentation of the optimized content to Google search engine or any other bot or crawler.
• Service Worker: Service worker is a script that runs in the browser in the background and provides the capability of running offline services such as automated processes or features that don’t require user interaction. Developers can build PWA with Service workers using the Angular 5 framework; this feature helps add much more depth to the features being built.

Switching to Angular 5

This step can be motivated by several advantageous features brought to the table by Angular 5 such as support of Typescript, PWA, the increased speed, advanced IDE, wider platform support, and MVW framework. Switching to Angular 5 from earlier versions is a compelling proposition from many points of view. It must be noted however that AngularJS can coexist with Angular 5 (or even earlier version like 2 or 4).

In order to reap the benefits of moving to Angular 5 from AngularJS, it is better to migrate based on the various upgrade recommendations and guidelines made by the Angular team. According to these guidelines, migration to Angular 5 requires preparatory steps such as adhering to AngularJS style guide, using module loaders, migrating to Typescript, and using component directives. Angular also provides a tool called ngUpgrade; this can be used to adopt step-by-step migration as it supports the coexistence of JavaScript and Typescript. Angular team suggests many steps in order to make an effective use of ngUpgrade. The guidelines also suggest some steps that are required to make Ahead-of-Time (AOT) compiler work with hybrid apps.

Future of Angular

Ever since the birth of AngularJS as a dynamic app framework in 2009, Angular team has been releasing a regular stream of Angular versions, such as JS, 2, 4 and 5 in a span of few years approximately. The current release is 5 and Angular 6 is just made available at the time of writing this whitepaper.

As the world of technology is evolving with unifying concepts such as Internet of Things (or IoT), Big Data, and Artificial Intelligence, there is a need for the technology platforms to keep pacing with the trends and advancements; Angular could be no exception to this. Reportedly, version 6 is focused lesser on the framework aspects and more focused on the toolchain. It may be worthwhile moving to this new framework but details must be worked out first. That is perhaps a matter for another discussion!

Originally posted on: Classic Informatics Blog