Understanding Modules

In NestJS, modules help organize and structure code by grouping related components. Each module represents a distinct and self-contained unit of functionality within an application. For example, a module might be responsible for handling user authentication or managing database connections. Additionally, developers can easily reuse modules across different parts of an application or share them between multiple applications, making modules a flexible and scalable solution for building complex systems.

Modules in NestJS

The @Module() decorator helps define a module. It takes an object that might contain several properties to configure the module. These properties can include controllers, providers, imports, and exports.

• controllers: The controllers property in the @Module decorator defines the set of controllers that belong to the module.

• providers: The providers property defines a set of objects, such as services and repositories, that components within the same module can inject and use.

• imports: The imports property refers to other modules required for the module to work. They can include modules from NestJS, third-party modules, or other modules in the application.

• exports: The @Module() decorator uses the exports property to make providers from the current module available to other modules that import it. By exporting providers, different modules can use them without redefining them, reducing duplication, and improving code organization.