Create custom roles guard and decorator


Keywords
nest, nestjs, nest.js, role, roles, guard, rbac
License
MIT
Install
npm install nestjs-roles@0.5.1-alpha.8ad897

Documentation

nestjs-roles

npm npm GitHub branch checks state Known Vulnerabilities Libraries.io Dependabot

Type safe roles guard with the decorator for controller made easy. Just specify how to get role from ExecutionContext. nestjs-roles will do the rest.

Install

npm i nestjs-roles

Example

First, let's define roles:

// role.enum.ts

export enum Role {
  ADMIN = 'ADMIN',
  USER = 'USER',
  MODERATOR = 'MODERATOR',
}

Let's say you use nestjs-session and keep role in session property object of request. So then create guard with getRole callback:

// roles.guard.ts

import { ExecutionContext } from '@nestjs/common';
import { createRolesGuard } from 'nestjs-roles';
import { Role } from './role.enum';

function getRole(context: ExecutionContext) {
  const { session } = context.switchToHttp().getRequest();

  if (!session) return;

  // you can use single role or array of roles
  // if you provide array of roles, the guard will pass if one of roles is in required roles
  return (session as { role?: Role | Role[] }).role;
}

export const Roles = createRolesGuard<Role>(getRole);

After that we can set Roles guard globally (don't forget to pass Reflector instance):

// bootstrap.ts

import { NestFactory, Reflector } from '@nestjs/core';
import { Roles } from './roles.guard';

const app = await NestFactory.create(AppModule);

const reflector = app.get<Reflector>(Reflector);
app.useGlobalGuards(new Roles(reflector));

All settings are done. Now you can set up access in your controllers:

// secrets.controller.ts

import { Roles } from './roles.guard';

@Controller('secrets')
@Roles.Params(true) // setup access on Controller for users with any existing role
export class SecretsController {

  @Get('my')
  async readMy() {
    // ...
  }

  @Patch(':id')
  @Roles.Params(Role.ADMIN) // override access on certain handler
  async update() {
    // ...
  }
}

Do you use this library?
Don't be shy to give it a star! ★

Also if you are into NestJS you might be interested in one of my other NestJS libs.