I was previously initializing my session stuff in my NestJS main.ts file, like this

import { NestFactory } from '@nestjs/core';
import { NestExpressApplication } from '@nestjs/platform-express';
import * as cookieParser from 'cookie-parser';
import * as session from 'express-session';
import * as sessionFileStore from 'session-file-store';
import { AppModule } from './app.module';

async function bootstrap(): Promise<void> {
  const app = await NestFactory.create<NestExpressApplication>(AppModule});

  const sessionTimeToLiveInSeconds = 60 * 60 * 12; //43200 seconds = 12 days
  const cookieMaxAgeInMilliseconds = 1000 * 60 * 60 * 24 * 7; //604800000 ms = 1 week
  const FileStore = sessionFileStore(session);
  const appFileStore = new FileStore({
    path: './sessions/',
    ttl: sessionTimeToLiveInSeconds,
  });

  app.use(
    session({
      secret: process.env.secret,
      resave: true,
      store: appFileStore,
      saveUninitialized: true, 
      cookie: {
        secure: process.env.environment !== 'dev',
        httpOnly: false,
        sameSite: false,
        maxAge: cookieMaxAgeInMilliseconds,
      },
    }),
  );

  app.use(cookieParser(process.env.secret)); //Allow session cookies

  //other stuff here...
});

And then I discovered the nestjs-session project, so I’ve installed it and moved everything over to my app.module.ts

import { Module } from '@nestjs/common';
import * as session from 'express-session';
import { NestSessionOptions, SessionModule } from 'nestjs-session';
import * as sessionFileStore from 'session-file-store';

@Module({
  imports: [
    SessionModule.forRootAsync({
      useFactory: (): NestSessionOptions => {
        const sessionTimeToLiveInSeconds = 60 * 60 * 12; //43200 seconds = 12 days
        const cookieMaxAgeInMilliseconds = 1000 * 60 * 60 * 24 * 7; //604800000 ms = 1 week
        const FileStore = sessionFileStore(session);
        const appFileStore = new FileStore({
          path: './sessions/',
          ttl: sessionTimeToLiveInSeconds,
        });

        return {
          session: {
            secret: process.env.secret,
            resave: true,
            store: appFileStore,
            saveUninitialized: true,
            cookie: {
              secure: process.env.environment !== 'dev',
              httpOnly: false,
              sameSite: false,
              maxAge: cookieMaxAgeInMilliseconds,
            },
          },
        };
      },
    }),
    
    //other modules go here

  ],
  controllers: [AppController],
})
export class AppModule {}

but when I try and do something that would access sessions I get:

ERROR [ExceptionsHandler] Login sessions require session support. Did you forget to use `express-session` middleware?

nestjs-session project is supposed to allow me to set up session in a module without having to manually set it up as an express interceptor. But this error message seems to be saying that I MUST set it up in main.ts.

I feel like either I am missing something obvious here or that the docs are missing some key information needed about how to set this up. What am I doing wrong?