In this article, we will explore how to implement authentication and authorization in a Nest.js application. We will cover the basics of authentication and authorization, and then dive into the specifics of implementing these concepts in a Nest.js application.
What is Authentication and Authorization?
Authentication and authorization are two fundamental concepts in computer security. Authentication is the process of verifying the identity of a user or system, while authorization is the process of determining what actions a user or system can perform.
Authentication
Authentication is the process of verifying the identity of a user or system. This can be done through various methods, such as:
- Username and password
- Two-factor authentication (2FA)
- OAuth
- OpenID Connect
Authorization
Authorization is the process of determining what actions a user or system can perform. This can be done through various methods, such as:
- Role-based access control (RBAC)
- Attribute-based access control (ABAC)
- Mandatory access control (MAC)
Implementing Authentication in Nest.js
To implement authentication in a Nest.js application, we will use the `@nestjs/passport` package. This package provides a set of decorators and classes that make it easy to implement authentication in a Nest.js application.
Installing the Required Packages
To get started, we need to install the required packages. We can do this by running the following command:
npm install @nestjs/passport passport-localCreating the Authentication Module
Next, we need to create the authentication module. This module will contain the logic for authenticating users.
import { Module } from '@nestjs/common';
import { PassportModule } from '@nestjs/passport';
import { LocalStrategy } from './local.strategy';
import { AuthService } from './auth.service';
@Module({
imports: [PassportModule],
providers: [LocalStrategy, AuthService],
})
export class AuthModule {}
Creating the Local Strategy
The local strategy is used to authenticate users using a username and password. We can create the local strategy by creating a new class that implements the `Strategy` interface.
import { Strategy } from 'passport-local';
import { PassportStrategy } from '@nestjs/passport';
import { Injectable } from '@nestjs/common';
import { AuthService } from './auth.service';
@Injectable()
export class LocalStrategy extends PassportStrategy(Strategy) {
constructor(private readonly authService: AuthService) {
super();
}
async validate(username: string, password: string): Promise {
const user = await this.authService.validateUser(username, password);
if (!user) {
throw new UnauthorizedException();
}
return user;
}
}
Creating the Authentication Service
The authentication service is used to validate users. We can create the authentication service by creating a new class that implements the `AuthService` interface.
import { Injectable } from '@nestjs/common';
import { UsersService } from '../users/users.service';
@Injectable()
export class AuthService {
constructor(private readonly usersService: UsersService) {}
async validateUser(username: string, password: string): Promise {
const user = await this.usersService.findOne(username);
if (!user) {
return null;
}
const isValid = await this.usersService.comparePassword(password, user.password);
if (!isValid) {
return null;
}
return user;
}
}
Implementing Authorization in Nest.js
To implement authorization in a Nest.js application, we can use the `@nestjs/roles` package. This package provides a set of decorators and classes that make it easy to implement authorization in a Nest.js application.
Installing the Required Packages
To get started, we need to install the required packages. We can do this by running the following command:
npm install @nestjs/rolesCreating the Authorization Module
Next, we need to create the authorization module. This module will contain the logic for authorizing users.
import { Module } from '@nestjs/common';
import { RolesModule } from '@nestjs/roles';
import { RolesGuard } from './roles.guard';
@Module({
imports: [RolesModule],
providers: [RolesGuard],
})
export class AuthModule {}
Creating the Roles Guard
The roles guard is used to authorize users. We can create the roles guard by creating a new class that implements the `CanActivate` interface.
import { Injectable } from '@nestjs/common';
import { CanActivate, ExecutionContext } from '@nestjs/common';
import { Reflector } from '@nestjs/core';
@Injectable()
export class RolesGuard implements CanActivate {
constructor(private readonly reflector: Reflector) {}
async canActivate(context: ExecutionContext): Promise {
const roles = this.reflector.get('roles', context.getHandler());
if (!roles) {
return true;
}
const request = context.switchToHttp().getRequest();
const user = request.user;
if (!user) {
return false;
}
const hasRole = roles.includes(user.role);
return hasRole;
}
}
Conclusion
In this article, we have explored how to implement authentication and authorization in a Nest.js application. We have covered the basics of authentication and authorization, and then dove into the specifics of implementing these concepts in a Nest.js application.
FAQs
What is authentication?
Authentication is the process of verifying the identity of a user or system.
What is authorization?
Authorization is the process of determining what actions a user or system can perform.
How do I implement authentication in Nest.js?
To implement authentication in Nest.js, you can use the `@nestjs/passport` package. This package provides a set of decorators and classes that make it easy to implement authentication in a Nest.js application.
How do I implement authorization in Nest.js?
To implement authorization in Nest.js, you can use the `@nestjs/roles` package. This package provides a set of decorators and classes that make it easy to implement authorization in a Nest.js application.
What is the difference between authentication and authorization?
Authentication is the process of verifying the identity of a user or system, while authorization is the process of determining what actions a user or system can perform.
Comments
Post a Comment