ACL Nest
ACL nestjs module functionality using casbin package.
Install package from npm.
npm i acl-nest --save
Usage
Module registration
First, register AccessControlModule into your App/Root module.
import {Module} from "@nestjs/common";
import {AccessControlModule} from "acl-nest/AccessControlModule";
import * as path from "path";
@Module({
imports: [
AccessControlModule.register(
'path to your model config or function wich returns model as text',
'path to your policy config or function wich returns policy as text',
(params, context, accessControlService)=>{
const request = context.switchToHttp().getRequest();
request.user = request.headers['x-user']
return accessControlService.hasPermission([request.user, ...params])
}
)
],
controllers: [YourController]
})
export class CustomTestingModule{}
Note: Example of casbin configurations can be found here
Adding controller
Decorate you controller methods
@Controller()
export class YourController {
@Get('getName')
@AccessControlAction(['name', 'read'])
public getName(): string {
return 'Bob'
}
}
Custom validation function
You can specify and override your validation logic if you need it.
Just define the function for validation the same as it is in the register module action.
@Controller()
export class YourController {
@Get('getLastName')
@AccessControlAction(['name', 'read'], (params, context, accessControlService) => {
const request = context.switchToHttp().getRequest();
return accessControlService.hasPermission([request.headers['x-user-name'], ...params])
})
public getLastName(): string {
return 'Wick'
}
}
Direct call of AccessControlService logic
Sometimes you need to check permission in the profound context of your application.
In this case, you can use AccessControlService directly. Just inject AccessControlService.
@Controller()
export class YourController {
public constructor(
private readonly accessControlService: AccessControlService
) {
}
@Get('getAge')
public async getAge(
@Req() request: Request
): Promise<number> {
await this.accessControlService.checkPermission([request.headers['x-user'], 'age', 'read'])
return 32;
}
}
Advanced usage
More complex logic before handling permissions
Sometimes is necessary to load some user data, or handle some requests to auth users before checking permissions.
But the registered validation function has available only ExecutionContext
which cannot help us to get some other service to load users for example.
A good approach here is to use middleware executed before Guards or register modules asynchronously.
1. Register Module asynchronous with injected dependencies
@Module({
imports: [
AccessControlModule.registerAsync({
inject: [UserService],
useFactory: (userService: UserService) => {
return {
modelPath: path.join(__dirname, '..', 'config', 'model.test.conf'),
policyPath: path.join(__dirname, '..', 'config', 'policy.test.conf'),
validationFunction: async (params, context, accessControlService) => {
const request = context.switchToHttp().getRequest();
const userName = await userService.getUserFromRequest(request)
return accessControlService.hasPermission([userName, ...params])
},
}
}
})
],
})
export class TestingModuleAsync {
}
2. Middleware usage
First create middleware
@Injectable()
export class UserMiddleware implements NestMiddleware {
constructor(
private readonly userService: UserService
) {}
public async use(req: any, res: any, next: () => void): Promise<any> {
req.userEntity = await this.userService.loadUser()
next()
}
}
Register middleware and write your validation function
@Module({
imports: [
AccessControlModule.register(
'path to your model config or function wich returns model as text',
'path to your policy config or function wich returns policy as text',
(params, context, accessControlService) => {
const request = context.switchToHttp().getRequest();
return accessControlService.hasPermission([request.userEntity.name, ...params])
}
)
],
providers: [UserService],
})
export class YourModule implements NestModule {
configure(consumer: MiddlewareConsumer): any {
consumer
.apply(UserMiddleware)
.forRoutes('*')
}
}
Multiple parameters
You can even specify multiple parameters like objects, and actions from a model.
@Controller()
export class YourController {
@Get('getNameAndAge')
@AccessControlAction([['name', 'age'], 'read'])
public getNameAndAge(): string {
return 'Bob 32'
}
@Get('writeNameAndAge')
@AccessControlAction([['name', 'age'], ['read', 'write']])
public writeNameAndAge(): string {
return 'Bob 32 written'
}
}
In this case, all combinations of specified parameters will be checked.
The reason why this functionality was created
is to have the option to check all permissions without specifying unnecessary aliases for other model properties.