backend/src/main.ts

import {
  BadRequestException,
  INestApplication,
  ValidationPipe,
} from '@nestjs/common';
import { NestFactory } from '@nestjs/core';
import cookieParser from 'cookie-parser';
import { ConfigService } from '@nestjs/config';
import { SwaggerModule } from '@nestjs/swagger';
import { API_PREFIX, createOpenApiDocument } from './openapi';
import { Logger } from 'nestjs-pino';
import { AppModule } from './app.module';
import { HttpExceptionFilter } from './common/filters/http-exception.filter';
import { RequestLoggingMiddleware } from './common/logging/request-logging.middleware';
import { StructuredLogger } from './common/logging/structured-logger.service';
import { Environment } from './config/env.validation';
import { shouldExposeSwagger } from './config/swagger.config';

export function configureApp(app: INestApplication): void {
  const config = app.get<ConfigService<Environment, true>>(ConfigService);
  const frontendOrigin = config.getOrThrow<string>('FRONTEND_ORIGIN');

  app.useLogger(app.get(Logger));
  app.enableCors({
    origin: frontendOrigin,
    credentials: true,
    exposedHeaders: ['X-Request-ID'],
  });
  app.setGlobalPrefix(API_PREFIX);
  app.use(cookieParser());
  const requestLogging = app.get(RequestLoggingMiddleware);
  app.use(requestLogging.use.bind(requestLogging));
  app.useGlobalPipes(
    new ValidationPipe({
      transform: true,
      whitelist: true,
      validationError: { target: false, value: false },
      exceptionFactory: (message) => new BadRequestException({ message }),
    }),
  );
  app.useGlobalFilters(new HttpExceptionFilter());
  app.enableShutdownHooks();
}

async function bootstrap() {
  const app = await NestFactory.create(AppModule, { bufferLogs: true });
  configureApp(app);
  const config = app.get<ConfigService<Environment, true>>(ConfigService);

  if (shouldExposeSwagger(process.env['NODE_ENV'])) {
    const document = createOpenApiDocument(app);
    SwaggerModule.setup('api/docs', app, document);
  }

  await app.listen(config.getOrThrow('PORT'));
  app.get(StructuredLogger).info('application.started', {
    service: 'wealth-ledger-backend',
    environment: process.env['NODE_ENV'] ?? 'development',
  });
}
if (require.main === module) void bootstrap();