Implement Role-Based Access Control

Role-based authorization is an access control mechanism that revolves around roles, allowing us to define who can do what. In this lesson, we’ll explore the principles behind role-based authorization, create custom guards, and learn how to implement defined authorization rules into the NestJS application.

What is RBAC?

RBAC is a security model where access permissions are assigned to roles, and users are associated with these roles in order to determine their access rights. It focuses on roles and privileges, allowing us to assign specific roles to users or entities within the application. Each role carries a set of permissions or access rights. Users or entities are then associated with roles, granting them access to the resources and actions permitted by those roles. RBAC provides an organized and scalable approach to controlling who can do what within our application.

Benefits of RBAC

RBAC offers several notable advantages:

• Fine-grained access control: RBAC enables us to define precise access rights for different roles, ensuring that users only have access to the features and data relevant to their role.

• Scalability: As our application grows, RBAC scales gracefully. Adding new roles or modifying permissions is relatively straightforward, making it adaptable to changing access requirements.

• Ease of maintenance: RBAC allows centralized roles and permission management, simplifying administration and maintenance. Changes can be made efficiently without affecting the entire application.

Implement RBAC

Implementing RBAC involves defining roles, assigning permissions to these roles, creating a role guard, and applying the role guard. This ensures a structured and controlled system where access to resources is based on the defined roles, enhancing the security and management of the application.

Defining roles

Roles represent a set of responsibilities or functions within the application. They can be associated with users or entities based on their access requirements. For example, in a typical web application, we might have roles like Admin, Writer, and Reader—each with distinct access rights.

In this example, we define a Role enum with three roles as follows: