Angular’s Dependency Injection: A Blessing or a Curse? — Hasan Teoman Tıngır

Angular, the JavaScript framework that developers either love or hate, with its fancy features and modern approaches to building web applications. Among its abundant offerings, one of the core features that stands out is dependency injection. You might wonder, “What on Earth is that?” Fear not, my fellow developers, for we shall dive into this mystical concept and unearth its secrets.

Prepare to be amazed, or perhaps perplexed, by Angular’s dependency injection!

Behold the Dependency Injection!

Dependency injection, the magical power bestowed upon Angular developers, is a technique that allows a class to receive its dependencies from an external source. The result? A clean and modular codebase, easier testing, and improved reusability.

Some might argue that dependency injection is just another “unnecessary complexity” of Angular. But let me tell you, dependency injection is to Angular what peanut butter is to jelly. It’s the power duo that makes large-scale applications manageable and development efficient. Why build everything from scratch when Angular can handle it for you?

Now that we’ve established the importance of dependency injection, let’s explore some common pitfalls and misconceptions that developers face when using it in Angular.

1. Ignorance is bliss (or is it?) Many developers, especially those new to Angular, are blissfully unaware of the existence of dependency injection. They might think, “Why bother reading the documentation when I can just wing it?” But let me tell you, this approach is like trying to navigate the ocean with a paper map and a broken compass. Dive into the documentation, and you shall find a treasure trove of knowledge!
2. Provider overload It’s easy to get carried away when using dependency injection, creating providers for every little thing. Sure, it’s powerful, but with great power comes great responsibility. Be selective about what you inject, lest your code becomes a tangled mess of injected dependencies.
3. Abusing singleton services Singleton services are great for sharing data and functionality across your application. However, use them sparingly and wisely. Overusing singleton services can lead to confusing code and unintended side effects. Remember, just because you can doesn’t mean you should.
4. Not leveraging providedIn The providedIn property in Angular allows you to define where a service should be provided. It can significantly reduce the size of your application bundle by only including services that are actually used. So, if you’re still manually providing your services in the NgModule, it’s time to level up your game.

Conclusion

Dependency injection in Angular is like a double-edged sword. When wielded skillfully, it can make your development journey a breeze. But if you’re careless, it can lead to an insurmountable mess. Take the time to understand and appreciate Angular’s dependency injection, and you’ll find yourself developing powerful, scalable, and efficient applications with ease.

So, go forth and conquer Angular, my friends, and may dependency injection be your loyal ally in the battlefield of web development!

For examples you can also read the following post from angular guide!

Originally published at https://blog.teoman.me on April 14, 2023.