如何将 Express.Multer.File 转换为 Blob 数据？

Question

我的控制器中有一个NestJs项目，我接受Express.Multer.File，但我需要将其发送到另一台服务器。如何将其转换为Blob以传递给FormData？

#action in my controller

    @Post('/upload')
    @UseInterceptors(FileInterceptor('avatar'))
    async uploadUserProfileAvatar(@UploadedFile() file: Express.Multer.File){
        
        console.log(file)
        let blob = new Blob(file.mimetype)
        let formData = new FormData()
        //can't set because file is not Blob
        formData.append('file',file)


        let request$ = this.httpService.post('http://test_server/file',formData,{headers:{
            'Content-Type':'multipart/form-data'
        }}).pipe(
            map(response => response.data)
        )

        request$.subscribe( response => {
            console.log(response)
            return response
        })
    }

我将感谢每一个答案！

编辑：

再次感谢你的帮助！结果，我成功地以这种方式发送了代码：

    @Post('/upload')
    @UseInterceptors(FileInterceptor('avatar'))
    async uploadUserProfileAvatar(@UploadedFile() file: Express.Multer.File){

        const FormData = require('form-data');
        const formData = new FormData();
        formData.append('file', Buffer.from(file.buffer) , file.originalname);


        let request$ = this.httpService.post('http://nginx_files/file',formData,{headers:formData.getHeaders()}).pipe(
                map(response => response.data)
            )

        request$.subscribe( response => {
            console.log(response)
            return response
        })
    }

Answer 1

使用formdata这样的包：

  const FormData = require('form-data');

  const formData = new FormData();
  formData.append('file', fileContent, 'file_name.ext');

  let request$ = this.httpService.post('http://test_server/file',
    formData,
    { headers: formData.getHeaders() }
  ).pipe(
            map(response => response.data)
        )