logger-context.middleware.ts

import { Injectable, NestMiddleware } from '@nestjs/common';
import type { Request, Response } from 'express';
import { PinoLogger } from 'nestjs-pino';

import { AuthService } from '../../auth';

@Injectable()
export class LoggerContextMiddleware implements NestMiddleware {
  // GraphQL logging uses the apollo plugins.
  // https://docs.nestjs.com/graphql/plugins
  // https://docs.nestjs.com/graphql/field-middleware

  constructor(
    private readonly logger: PinoLogger,
    private auth: AuthService,
  ) {}

  public use(req: Request, _res: Response, next: () => void): void {
    const authorization = req.header('authorization');

    const user = authorization?.startsWith('Bearer') ? this.auth.getPayload(authorization.split(' ')[1]) : req.user;

    const userId = user?.userId;
    // for https://github.com/iamolegga/nestjs-pino/issues/608
    req.customProps = { userId };
    // Add extra fields to share in logger context
    this.logger.assign(req.customProps);

    next();
  }
}