how to store images in unique folder(using primary key) for each upload using multer in nest js - node.js

Question

I have an application where i want to store multipart form data along with image. I want images to be stored in unique folder which is primary id. How can i do it.
Here i am saving multiform data in database. I want to use primary id return by below function to create folder to save its respective images.
async createFaceDetection(faceDetectionReqDto: FaceDetectionReqDto): Promise<Object> {
try {
const newFaceDetection = new face_detection({
Name: faceDetectionReqDto.Name
})
const savedMediaUpload = await this.FaceDetectionRepository.save(newFaceDetection);
return savedMediaUpload
}
catch (err) {
throw err;
}
}
how can i use primary id fetched by "savedMediaUpload" variable in multer
my component.controller.ts code
#UseInterceptors(
FilesInterceptor('Images', 20,
{
storage: diskStorage({
destination: async function (req, file, cb) {
const filePath = path.join(ROOT_DIR, FACE_DETECTION_PATH, {Primary-Id}) // (primary id
generated by above function.)
if (!existsSync(`${filePath}`)) { mkdirSync(filePath, { recursive: true }) }
cb(null, filePath);
},
filename: (_req, file, cb) => {
return cb(null, file.originalname);
},
}),
}),
)

Answer 1

I've done it like this, by appending generated UUID to the file name - may not be perfect but works good enough for me so far:
Controller:
#UseInterceptors(
FilesInterceptor('asset', 10, {
storage: diskStorage({
destination: UPLOADS_DIR,
filename: getUniqueFileName,
}),
limits: {
fileSize: MAX_FILE_SIZE_BYTES,
},
fileFilter: validateImageFile,
}),
)
#Post()
async createAsset(
#Body() assetCreateRequest: AssetCreateRequest,
#UploadedFile() asset: UploadedFileModel,
): Promise<AssetResponse[]> {
....
}
And getUniqueFileName looks like this:
import { extname } from 'path';
import { v4 as uuidv4 } from 'uuid';
import { UploadedFileModel } from '../../dto/internal/file-upload';
export const getUniqueFileName = (
_request: unknown,
file: UploadedFileModel,
callback: (error: Error | null, fileName: string) => void,
) => {
const name = file.originalname.split('.')[0];
const extension = extname(file.originalname);
const randomUuid = uuidv4();
callback(null, `${name}-${randomUuid}${extension}`);
};
Later on in the database, I have separate Asset and e.g. User tables where User references a record in the Asset table by foreign key, and Asset record contains all the necessary info - file name, path, URL etc.