NestJS req.body from POST method is empty/undefined when awaiting ArrayBuffer - post

Question

I am trying to send file from Client (Angular) to the NestJS same way like it is working now with Java-springboot API.
I am using POST method in NestJS but, unfortunatelly I am not able to got any data from the body :
here is the code :
#Post('/uploadExportFile')
uploadAttachment(#Req() req: Request, #Body() attachment: ArrayBuffer): any {
console.log(attachment);
return {};
}
content-type is set in header on Client side, I am not sure if I need to set content-types there ? Content type depends on file mimetype it should be (application/pdf/png/jpeg)..not multiform or what I need to do to achieve that attachment object will not return empty {} .
req.body is undefined
What I need to do with that file is to again change it back to Base64 (in angular it is in Base64) but Java API consumes only byte[] so I need to keep that like it is on FE.
any suggestions what is wrong in this "simple" code?
** EDIT **
====↓ EDIT ↓====
Solution: request.body is undefined is:
NestJS use as default body jsonBody, so in that case you have to override for specific routes that you want to use raw-body, and if raw-body is used insted of jsonBody, then the body from request is not undefined and it contain ArrayBuffer.
What you need to do is something like this;
Create rawBody middleware raw-body.middleware.ts
import { Injectable, NestMiddleware } from '#nestjs/common';
import { Request, Response } from 'express';
import * as bodyParser from 'body-parser';
#Injectable()
export class RawBodyMiddleware implements NestMiddleware {
use(req: Request, res: Response, next: () => any) {
bodyParser.raw({type: '*/*'})(req, res, next);
}
}
app.module.ts
export class AppModule implements NestModule {
public configure(consumer: MiddlewareConsumer): void {
consumer
.apply(RawBodyMiddleware)
.forRoutes({
path: '/uploadExportFile',
method: RequestMethod.POST,
})
.apply(JsonBodyMiddleware)
.forRoutes('*');
}
}
and you need to disable bodyparser in main.ts
const app = await NestFactory.create(AppModule, { bodyParser: false })
in new version of NestJS is introduced new option raw-body but I have no possibility to test that https://docs.nestjs.com/faq/raw-body#raw-body

Answer 1

frist thing send the content-type application/x-www-form-urlencoded
and sure you have add UseInterceptors Like FileInterceptor
you can import FileInterceptor
if you need to get buffer try use file.buffer
import {FileInterceptor} from "#nestjs/platform-express";
#Post('upload')
#UseInterceptors(FileInterceptor('file'))
async upload(#Req() request: RequestWithUser, #UploadedFile() file) {
if (!file) {
throw new HttpException('File is required', HttpStatus.BAD_REQUEST);
}
// you have file
return await this.storageService.upload(file, request.user);
}