Two sessions being saved to store

[averybuehler]

I'm trying to implement session-based authentication in Nest.js using Passport.js and I've run into an issue. For reference, I'm using pg-connect-simple to configure the store with PostgreSQL.

I have this route:

@UsePipes(ValidationPipe)  
  @Post('register')  
  async registerUser(
    @Body() registerUserDto: RegisterUserDto,
    @Req() request: Request,
  ): Promise<Omit<User, 'password'>> {
    console.log('1 -- ', request.sessionID);
    return this.userService.create(registerUserDto).then((user) => {
      console.log('2 -- ', request.sessionID);
      request.logIn(user, () => {
        console.log('3 -- ', request.sessionID);
      });
      const { password, ...userData } = user;
      return userData;
    });
  }

What I see in the console is this:

1 --  NWdZEuZFqg4tWoQKPMHOW6BjNE9Y-3ML
2 --  NWdZEuZFqg4tWoQKPMHOW6BjNE9Y-3ML
2.5 -- serializing user
3 --  OBoHcDJkAIRTCQh0yM1TrRlUc6TKrnsY

This is what gets stored in the database:

I don't understand why request.sessionID is changing, and that's the root of my issue. The session with the id of NWdZEuZFqg4tWoQKPMHOW6BjNE9Y-3ML gets returned to the client and is not logged in. The session with the id of OBoHcDJkAIRTCQh0yM1TrRlUc6TKrnsY, however, is logged in but is never sent to the client (because the first session was). I don't understand why the session id is changing because it's not allowing me to authenticate the user upon registering.

The ideal behavior is for only one session to be created, for that session to be logged in, and for that session to be returned to the client.

Does anyone have any insight into what might be causing this? I've been troubleshooting forever but can't find any solutions.