docs.nestjs.com: NestJS Authenticated sessions documentation has major gaps and is seemingly wrong

I was able to get this working – here’s the solution I came up with:

configure sessions and passport to use sessions

In main.ts (or wherever you’re settting up nest):

app.use(session({
    secret: 'CHANGEME',
    resave: false,
    saveUninitialized: false,
  }));
  app.use(passport.initialize());
  app.use(passport.session());

session from the express-session package.

guards

I’m using passport-local so my LocalAuthGuard class looks like this:

import { Injectable, ExecutionContext, UnauthorizedException, Logger } from '@nestjs/common';
import { AuthGuard } from '@nestjs/passport';

@Injectable()
export class LocalAuthGuard extends AuthGuard('local') {
    async canActivate(context: ExecutionContext): Promise<boolean> {
        const request = context.switchToHttp().getRequest();
        const result = (await super.canActivate(context) as boolean); // THIS MUST BE CALLED FIRST
        await super.logIn(request);
        return result;
    }

    handleRequest(err, user, info) {
        if (err || !user) {
            throw err || new UnauthorizedException();
        }

        return user;
    }
}

configure the serializer

If you look at the implementation of PassportSerializer (from @nestjs/passport) you’ll notice that both serializeUser and deserializeUser are abstract…so they need to be implemented by you. Take a look: https://github.com/nestjs/passport/blob/master/lib/passport/passport.serializer.ts

My barebones serializer looks like this:

import { PassportSerializer } from '@nestjs/passport';
import { Injectable } from '@nestjs/common';

@Injectable()
export class CookieSerializer extends PassportSerializer {
    serializeUser(user: any, done: (err: any, id?: any) => void): void {
        done(null, user);
    }

    deserializeUser(payload: any, done: (err: any, id?: any) => void): void {
        done(null, payload);
    }
}

update auth module

Then in the module (for example I’m using AuthModule), this needs to be included. So my AuthModule class looks like this:

import { Module } from '@nestjs/common';
import { AuthService } from './auth.service';
import { AuthController } from './auth.controller';
import { LocalStrategy } from './strategies/local.strategy';
import { PassportModule } from '@nestjs/passport';
import { CookieSerializer } from './cookie.serializer';

@Module({
    imports: [
        PassportModule.register({session: true}),
    ],
    providers: [AuthService, LocalStrategy, CookieSerializer],
    controllers: [AuthController],
    exports: [PassportModule],
})
export class AuthModule { }

session guard

Create a guard to check to see if the user is in the session.

import { CanActivate, ExecutionContext, UnauthorizedException } from '@nestjs/common';

export class SessionGuard implements CanActivate {
    canActivate(context: ExecutionContext): boolean | Promise<boolean> {
        const httpContext = context.switchToHttp();
        const request = httpContext.getRequest();

        try {
            if (request.session.passport.user) {
                return true;
            }
        } catch (e) {
            throw new UnauthorizedException();
        }

    }
}

putting it all together

Here is how this can be used in a controller:

import { Controller, Get, Post, Param, Body, UseGuards, HttpCode, HttpStatus, Req } from '@nestjs/common';
import { CreateUserDto } from './dto/createUser';
import { AuthGuard } from '@nestjs/passport';
import { LoginCredentialsDto } from './dto/login.dto';
import { LocalAuthGuard } from './guards/local.guard';
import { SessionGuard } from './session.guard';
import { SessionUser } from './sessionuser.decorator';

@Controller('auth')
export class AuthController {
    @Get('me')
    @UseGuards(SessionGuard)
    getMetadataArgsStorage(@SessionUser() user: any) {
        return user;
    }

    @Post('login')
    @HttpCode(HttpStatus.OK)
    @UseGuards(LocalAuthGuard)
    login(@Body() login: LoginCredentialsDto, @Req() req): Promise<any> {
        return;
    }
}

You can test this out with cURL/Postman:

Logging in:

$ curl -X POST http://localhost:3000/auth/login -d "username=jdoe&password=1" -v
*   Trying ::1...
* TCP_NODELAY set
* Connected to localhost (::1) port 3000 (#0)
> POST /auth/login HTTP/1.1
> Host: localhost:3000
> User-Agent: curl/7.54.0
> Accept: */*
> Content-Length: 23
> Content-Type: application/x-www-form-urlencoded
>
* upload completely sent off: 23 out of 23 bytes
< HTTP/1.1 200 OK
< X-Powered-By: Express
< Set-Cookie: connect.sid=s%3ADuKdgMobTzL7pHXa9oszUqYRy2J85Eiv.11yD1Gq3NwgdSASUfBYU%2B7sxBIwLH9bqwv1pGtq2T%2BU; Path=/; HttpOnly
< Date: Thu, 25 Apr 2019 21:44:25 GMT
< Connection: keep-alive
< Content-Length: 0
<
* Connection #0 to host localhost left intact

Then to test it out:

$ curl -X GET http://localhost:3000/auth/me -H 'Cookie: connect.sid=s%3AfBdKLAFybLq6xh13NeET3LDEQjfxv7cD.XyZanjMKgAq9SlBUVcDsCdZxJn0auKCgWZCnczaLczQ' -v
*   Trying ::1...
* TCP_NODELAY set
* Connected to localhost (::1) port 3000 (#0)
> GET /auth/me HTTP/1.1
> Host: localhost:3000
> User-Agent: curl/7.54.0
> Accept: */*
> Cookie: connect.sid=s%3ADuKdgMobTzL7pHXa9oszUqYRy2J85Eiv.11yD1Gq3NwgdSASUfBYU%2B7sxBIwLH9bqwv1pGtq2T%2BU
>
< HTTP/1.1 200 OK
< X-Powered-By: Express
< Content-Type: text/html; charset=utf-8
< Content-Length: 43
< ETag: W/"2b-p23HHgfkAEp1vHx70BYS/ngFWwQ"
< Date: Thu, 25 Apr 2019 21:51:04 GMT
< Connection: keep-alive
<
* Connection #0 to host localhost left intact
{"firstName":"John","lastName":"Doe"}

Thanks @kamilmysliwiec for all your work on NestJS – seems very slick!

Hi all,

After digging into whole Nestjs framework, I find it really cool. But, the security aspects are very painful. Implementing a simple local-strategy session should not be as difficult as the code @TrejGun has provided (thanx for that btw). We have to provide :

• local strategy class
• canActivate handler
• serializer/deserializer
• findUser service and so forth
• Custom annotations

Look at this snippet from Spring Security for example :

@RestController
@RequestMapping("/api")

public class TestService {
    @Secured("ROLE_USER")
    @RequestMapping("/currentUser")    
    public Principal information(Principal principal) {    
       return principal;
    }

  @PreAuthorize("hasRole('ROLE_USER') and hasRole('ROLE_TRAINER')")    
  @RequestMapping("/courses")    
   public List<Course> courses() {        
      return courseDAO.getCourses(); 
   }}

This code can be used for LDAP, local strategy, Google/Facebook and whatever you want without changing any single line of code in your controllers.

With UserGuard/Auth annotations, we tie the controllers code with custom annotations. There’s no notion of Principal, only req.session.passport user which is very low level.

We should be able to say in app.module that we want a Passport local strategy (session/basic or other) and all the boilerplate code that we generally see should be generated or implemented in NestJS for us.

My 2 cents

Sami

Would be great to split the documentation example into two paths after setting up everthing: 1. Session, 2. JWT. Session is industry-standard for authentication IMO.

I’ll make sure to update this chapter as soon as I can. It’s indeed way too complicated right now

This article covers sessions in detail. Has been reviewed by the NestJS core team. https://dev.to/nestjs/authentication-and-sessions-for-mvc-apps-with-nestjs-55a4

I’ll wait a few days to see if there are any further comments before closing.

I love NestJS but I can’t believe how hard it’s to have a simple session auth setup correctly in 2022. I agree with @mikehaertl. Sessions should be the most basic auth way to implement. Even if JWT is more popular lately, in Rails for example you can get session auth running in a few minutes.

@mikehaertl honestly, I’m with you. I find that, at least for login and signup with a local username and password, passport is total overkill. I personally opt not to use it in cases that I really don’t need to, and instead prefer to implement that logic myself. If you know what you’re doing with a hashing library, it’s a pretty straightforward integration and you can either set up a session or a JWT to be checked in subsequent requests (either by passport or by your own guard).

It still requires manual setup of passport, i.e. a call to passport.initialize() and passport.session()

This is only if you want passport to manage sessions, (which I realize is what this thread is about but still pointing that fact out). We can’t outright bind them because if someone wants to use fastify (even though it doesn’t play the best with passport) those middleware won’t work, which is really annoying. It also makes adding your own session store easier, though there should probably be better ways around that

It breaks validation as pipes are exectued after guards. I.e. if I have a dto with an email field as username I can not validate the email address with class-validator (unless I rebuild the validation logic in yet another guard, as someone suggested on Discord)

Yeah, this is kind of unfortunate, though if you implement the login logic yourself (i.e. without passport) then this shouldn’t be a problem because the AuthGuard() won’t be executed. Also, if the email in invalid the guard should return a 401/403 depending on how you have passport set up

The whole setup has so many moving parts and is extremely hard to follow. Which would not be a problem per se if the actual task wasn’t so easy without nest.

This is why I wrote the article a few comments above that should help demystify what is happening between Nest and passport

Given all this I wonder why we can’t use a simple controller action or - as I’m using GraphQL - a mutation as usual. Something like this:

You can, and in fact I suggest you do. passport-local is incredibly cumbersome for what it does and causes so many headaches for new devs.

As a newcomer to nestjs all this makes me raise my eyebrows. It would be great to get some feedback from the developers about why the design decision was made that way.

Part of the reason this all feels so wonky is because passport is old (it was originally designed for connect, express’s predecessor) but it is also tried and true. It’s documentation is also iffy at best, which is another pain point for a lot of people.

If I can find the time I’d love to rip it out and make a @nestjs/auth which can handle local, jwt, cookie, and session based authentication, and maybe help with oauth, so that passport isn’t necessary anymore and we can just have something that is transport agnostic as that’s really what Nest is striving to be. Unfortunately, designing something like that is going to take a lot of time and testing, which in turn means that it’s going to really need a lot of work and dedication that I can’t always give to it.

To add another resource, there’s this article by me that does a deep dive on passport with Nest and shows how to set up a session based authentication with passport, Nest, and Redis

you can find my version of solution in my blog, there are also other articles about nest.js https://trejgun.github.io/

Is it just me or does the documented solution feel very strange?

1. It uses a guard to perform the actual login. To me this sounds like a mutation. Guards should not do mutations IMO. (From the docs: “Guards have a single responsibility. They determine whether a given request will be handled by the route handler or not”)
2. It still requires manual setup of passport, i.e. a call to passport.initialize() and passport.session()
3. It also requires manual call of login() even though passport usually does that automatically under the hood. Why?
4. It breaks validation as pipes are exectued after guards. I.e. if I have a dto with an email field as username I can not validate the email address with class-validator (unless I rebuild the validation logic in yet another guard, as someone suggested on Discord)
5. Making it work with your own DTO complicates things even more as you have to manually read out the DTO object from the request and set the parsed object on req.body to let passport-local do it’s job
6. The whole setup has so many moving parts and is extremely hard to follow. Which would not be a problem per se if the actual task wasn’t so easy without nest.

Given all this I wonder why we can’t use a simple controller action or - as I’m using GraphQL - a mutation as usual. Something like this:

import { LoginUserInput } from './dto/login-user.input';
import { AuthService } from './auth.service';

export class AuthResolver {
  constructor(private authService: AuthService) {}

  @Mutation(() => User, { name: 'login' })
  async loginUser(
    @Args('loginUserInput') loginUserInput: LoginUserInput,
    @Context('req') req
  ) {
    const user = await this.authService.validateUser(loginUserInput);
    if (!user) {
      // @todo: report error 
    }
    req.login(user);
    return user;
  }
}

And use AuthGuard only for those actions that I want to protect from unauthenticated access.

I tried this but req.login() is not defined - even though I’ve initialized passport in the app module.

As a newcomer to nestjs all this makes me raise my eyebrows. It would be great to get some feedback from the developers about why the design decision was made that way.

EDIT: I made it work (forgot to call forRoutes('*') after consumer.apply(...) in the app module’s configure()). So the question remains: Why all the fuss with guards and what-not if a simple setup like this just seems to work?

I was able to get this working – here’s the solution I came up with:

configure sessions and passport to use sessions

In main.ts (or wherever you’re settting up nest):

app.use(session({
    secret: 'CHANGEME',
    resave: false,
    saveUninitialized: false,
  }));
  app.use(passport.initialize());
  app.use(passport.session());

session from the express-session package.

guards

I’m using passport-local so my LocalAuthGuard class looks like this:

import { Injectable, ExecutionContext, UnauthorizedException, Logger } from '@nestjs/common';
import { AuthGuard } from '@nestjs/passport';

@Injectable()
export class LocalAuthGuard extends AuthGuard('local') {
    async canActivate(context: ExecutionContext): Promise<boolean> {
        const request = context.switchToHttp().getRequest();
        const result = (await super.canActivate(context) as boolean); // THIS MUST BE CALLED FIRST
        await super.logIn(request);
        return result;
    }

    handleRequest(err, user, info) {
        if (err || !user) {
            throw err || new UnauthorizedException();
        }

        return user;
    }
}

configure the serializer

If you look at the implementation of PassportSerializer (from @nestjs/passport) you’ll notice that both serializeUser and deserializeUser are abstract…so they need to be implemented by you. Take a look: https://github.com/nestjs/passport/blob/master/lib/passport/passport.serializer.ts

My barebones serializer looks like this:

import { PassportSerializer } from '@nestjs/passport';
import { Injectable } from '@nestjs/common';

@Injectable()
export class CookieSerializer extends PassportSerializer {
    serializeUser(user: any, done: (err: any, id?: any) => void): void {
        done(null, user);
    }

    deserializeUser(payload: any, done: (err: any, id?: any) => void): void {
        done(null, payload);
    }
}

update auth module

Then in the module (for example I’m using AuthModule), this needs to be included. So my AuthModule class looks like this:

import { Module } from '@nestjs/common';
import { AuthService } from './auth.service';
import { AuthController } from './auth.controller';
import { LocalStrategy } from './strategies/local.strategy';
import { PassportModule } from '@nestjs/passport';
import { CookieSerializer } from './cookie.serializer';

@Module({
    imports: [
        PassportModule.register({session: true}),
    ],
    providers: [AuthService, LocalStrategy, CookieSerializer],
    controllers: [AuthController],
    exports: [PassportModule],
})
export class AuthModule { }

session guard

Create a guard to check to see if the user is in the session.

import { CanActivate, ExecutionContext, UnauthorizedException } from '@nestjs/common';

export class SessionGuard implements CanActivate {
    canActivate(context: ExecutionContext): boolean | Promise<boolean> {
        const httpContext = context.switchToHttp();
        const request = httpContext.getRequest();

        try {
            if (request.session.passport.user) {
                return true;
            }
        } catch (e) {
            throw new UnauthorizedException();
        }

    }
}

putting it all together

Here is how this can be used in a controller:

import { Controller, Get, Post, Param, Body, UseGuards, HttpCode, HttpStatus, Req } from '@nestjs/common';
import { CreateUserDto } from './dto/createUser';
import { AuthGuard } from '@nestjs/passport';
import { LoginCredentialsDto } from './dto/login.dto';
import { LocalAuthGuard } from './guards/local.guard';
import { SessionGuard } from './session.guard';
import { SessionUser } from './sessionuser.decorator';

@Controller('auth')
export class AuthController {
    @Get('me')
    @UseGuards(SessionGuard)
    getMetadataArgsStorage(@SessionUser() user: any) {
        return user;
    }

    @Post('login')
    @HttpCode(HttpStatus.OK)
    @UseGuards(LocalAuthGuard)
    login(@Body() login: LoginCredentialsDto, @Req() req): Promise<any> {
        return;
    }
}

You can test this out with cURL/Postman:

Logging in:

$ curl -X POST http://localhost:3000/auth/login -d "username=jdoe&password=1" -v
*   Trying ::1...
* TCP_NODELAY set
* Connected to localhost (::1) port 3000 (#0)
> POST /auth/login HTTP/1.1
> Host: localhost:3000
> User-Agent: curl/7.54.0
> Accept: */*
> Content-Length: 23
> Content-Type: application/x-www-form-urlencoded
>
* upload completely sent off: 23 out of 23 bytes
< HTTP/1.1 200 OK
< X-Powered-By: Express
< Set-Cookie: connect.sid=s%3ADuKdgMobTzL7pHXa9oszUqYRy2J85Eiv.11yD1Gq3NwgdSASUfBYU%2B7sxBIwLH9bqwv1pGtq2T%2BU; Path=/; HttpOnly
< Date: Thu, 25 Apr 2019 21:44:25 GMT
< Connection: keep-alive
< Content-Length: 0
<
* Connection #0 to host localhost left intact

Then to test it out:

$ curl -X GET http://localhost:3000/auth/me -H 'Cookie: connect.sid=s%3AfBdKLAFybLq6xh13NeET3LDEQjfxv7cD.XyZanjMKgAq9SlBUVcDsCdZxJn0auKCgWZCnczaLczQ' -v
*   Trying ::1...
* TCP_NODELAY set
* Connected to localhost (::1) port 3000 (#0)
> GET /auth/me HTTP/1.1
> Host: localhost:3000
> User-Agent: curl/7.54.0
> Accept: */*
> Cookie: connect.sid=s%3ADuKdgMobTzL7pHXa9oszUqYRy2J85Eiv.11yD1Gq3NwgdSASUfBYU%2B7sxBIwLH9bqwv1pGtq2T%2BU
>
< HTTP/1.1 200 OK
< X-Powered-By: Express
< Content-Type: text/html; charset=utf-8
< Content-Length: 43
< ETag: W/"2b-p23HHgfkAEp1vHx70BYS/ngFWwQ"
< Date: Thu, 25 Apr 2019 21:51:04 GMT
< Connection: keep-alive
<
* Connection #0 to host localhost left intact
{"firstName":"John","lastName":"Doe"}

Thanks @kamilmysliwiec for all your work on NestJS – seems very slick!

Hey, really helpful this! 😃 But, only thing i am still bothered about is why do i need to bootstrap the initialize and session methods, especially when we can do that in the module initialisation like so:

PassportModule.register({ session: true });

I know, without the initialisation the solution doesn’t work but then why is there an option to register a session in the module?

Thanks again!

Example project how to use session in NestJS https://github.com/Insidexa/nestjs-session-example

The solutions provided in the issue make absolutely zero sense to me as a new user of NestJS.

It would be great if someone could update the documentation with how sessions work together with NestJS, express, express-session, and passport with the local guard.

@ejhayes You don’t happen to have this example in a public git repo? I don’t understand where CookieSerializer is used