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Kanika for Errsole

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Let Nest.js take your Node backend framework to the next level

Nest is one of the best things to happen to server-side JavaScript programming in a long time.
The world is ruled by JavaScript! With the emergence of Node.js, JavaScript can now be used outside of the browser and has become the language of everything.

This progression resulted in the development of many Node backend frameworks for developing server-side JavaScript applications. Express, Hapi, and Meteor JS are just a few examples.

A new youngster on the block has recently arrived. NestJS!

NestJS is a backend framework that allows you to build scalable apps. It functions as an abstraction on top of the underlying HTTP server library.

In this blog, you will explore the essentials of the Node backend framework with Nest.js. Let’s first see what Nest.js is and become acquainted with the fundamental building pieces of Nest apps with the node framework.

What Is Nest.js framework?

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Nest.js is one of the fastest-growing Node.js frameworks for developing efficient and enterprise-grade Node.js backend applications.

It is well-known for creating apps that are highly testable, manageable, and scalable by using current JavaScript and TypeScript. It accomplishes this by using express under the hood. It functions as an additional layer, making many things easier for us.

The framework is a popular go-to for crafting your Node.js backend project, with over 46.6k stars and 5.4k forks on GitHub and a weekly download count of up to 700,000.

Although Nest is relatively rigid about its codebase — its modules, services, and controllers — you can’t go wrong with it.

Nest takes scalable Node.js servers to an entirely new level.

Let’s take a closer look at some of the things that make Nest so unique and why you should consider writing your next backend project in NestJS.

Take your Node backend framework to the next level with NestJS

In the following section, we’ll go through various abstractions/concepts that will assist you in determining where to put specific business logic from project to project using Nest.js- a node.js framework.

1. Language

We adore TypeScript, but above everything, we love using Node.js as our backend framework to create applications. As a result, Nest works with both TypeScript and JavaScript. Nest makes use of the most recent language features. Hence it requires a Babel compiler to be used with vanilla JavaScript.

We’ll largely use TypeScript in our examples, but you can always change the code snippets to plain JavaScript syntax.

2. Architecture

The majority of server-side JavaScript frameworks do not address architecture. They give you a lot of freedom in terms of how you do and organize things. As a result, in my experience, it takes a lot of planning to have clear techniques and standards on how to write things.

NestJS differs significantly from the other NodeJS frameworks in this regard. While competing frameworks don’t supply many architectural notions, NestJS provides a well-thought-out project setup.

It was one of the primary motivations for its construction. To solve the architectural problem!

By presenting a few fundamental building components, the most significant of which are modules, services, and controllers, Nest abstracts away all transactions with underlying libraries such as Express or Fastify.

Nest, being inspired by Angular, makes use of the fundamental building pieces found in Angular. Let’s go over the most significant ones.

3. Modules

A module is a class that has been annotated with the @Module() decorator. Nest uses the metadata provided by the @Module() decorator to organize the application structure.

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Modules in this node.js backend framework are critical components, and each application must have at least one: the application root module. Nest begins by building the application graph from the root module.

A module should contain the post service, controller, post object, and everything relevant to posting (PostsModule). The PostsModule is specified further down.

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The module is then imported into the root module AppModule:

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4. Controllers

Nests backend frameworks controllers are simply fantastic!

Controllers are in charge of receiving incoming requests and responding to the client. Nest.js use controllers in tandem with annotations. The annotation @Controller specifies that this class serves as a controller.

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REST is a key design element for modern APIs. It provides us with a common method for creating an interface to the outside world that our client apps can utilize to communicate with our server.

Instead of directly accessing the body or a query via the request object (like we would in Express), each argument can be decorated with @param, @Query, or @Body, abstracting the underlying access layer.

Then, for each method, an HTTP verb and a path can be added. The route is then function-specific. @Get, @post, @Put, and @Delete are the most commonly used decorators.

Not only is the controller syntax excellent. Nest offers Open API support in the form of Swagger. Swagger is simple to integrate into our backend and makes the API visible to front-end developers.

5. Services

A service is a class that has the @Injectable decorator added to it. It includes domain logic (business logic). We have a clear separation of concerns by separating the access layer (controllers) and the logic layer (services).

We can notify Nest.js that this class may be injected into other areas of the program by using the @Injectable decorator.

6. File structure

It is strongly advised that the folder structure reflect the structure of the codebase. A module should have its own folder containing its internal construction blocks.

NestJS File Structure looks like:

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Nest, like Angular, has a naming convention that includes the relevant file endings such as.controller, .service, and .module. The project’s folder structure is now immediately visible, and the developer has a decent overview of the coding.

7. CLI

Another reason for using the node backend framework with Nestjs in that it includes its own CLI.

npm i -g @nestjs/cli

New and generate are the most critical commands.

The new command allows us to generate a starting application’s boilerplate with Nest quickly.

The generate command creates a collection of files for a specific feature. If necessary, it may also change the current ones.

In addition, if a module were defined in the directory, the service would be imported automatically.

The CLI boosts developer productivity by minimizing the boilerplate required for each building block and by generating a .spec file with some very simple tests written in it.

8. Testing

It is critical to ensure that the application continues to function properly when modifications are made. Nest takes testing seriously and offers testing facilities to make the process as easy as possible.

Because of Nest’s custom providers feature, it is very simple to mock out the modules we are not currently testing using dependency injection.

Fully-fledged backend framework

Nest is a fantastic framework, and in my opinion, it is one of the best node backend frameworks for server-side programming.

Working with Nest taught me to value the architectural concepts it gives out of the box. Nest-written JavaScript backends feel more stable and scalable.

The principles and benefits detailed above are just a sampling of Nest’s feature set. Nest with node backend framework supports a wide range of technologies and approaches to meet a wide range of needs.

We get a tremendous productivity and performance increase because of the amazing ecosystem of Nest-compatible tools and packages.

You should definitely give this framework a try whether you are an Angular developer or not.

Do you want to improve your Node application code? Don’t pass up this chance to debug your node.js application within minutes, irrespective of the framework- nest.js or express.js.

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kanika_a profile image

Capture, Reproduce & Debug Node.js Errors using - Errsole


11 Tips That Make You a Better Typescript Programmer

1 Think in {Set}

Type is an everyday concept to programmers, but it’s surprisingly difficult to define it succinctly. I find it helpful to use Set as a conceptual model instead.

#2 Understand declared type and narrowed type

One extremely powerful typescript feature is automatic type narrowing based on control flow. This means a variable has two types associated with it at any specific point of code location: a declaration type and a narrowed type.

#3 Use discriminated union instead of optional fields


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