Confusion between buffer file and csv when using csv-parse in nodejs-CodePudding

I want to parse a csv file coming from a react app. I have a controller which gets the csv file:

@Post(':id/transactions/upload')
  @UseInterceptors(FileInterceptor('file'))
  uploadTransactions(
    @Body() body: any,
    @UploadedFile() file: Express.Multer.File,
  ) {
    return this.accountsUsersService.uploadTransactions(file.buffer);
  }

and following service:

async uploadTransactions(buffer) {
    console.log('### buffer', buffer);
    const readBuffer = buffer.toString();
    console.log('### readBuffer', readBuffer);
    const csvData = [];
    createReadStream(buffer) // tried many tings
      .pipe(
        parse({
          delimiter: ';',
        })
        .on('data', function (dataRow) {
          csvData.push(dataRow);
        })
        .on('end', function() {
          console.log('### csvData', csvData)
        })
      )

    return 'uploaded transactions successfully';
  }

Here are the console.logs:

### buffer <Buffer 61 6c 62 65 72 74 3b 74 65 73 74 0a 6a 6f 61 6e 61 3b 67 6f 6f 64 0a>
### readBuffer albert;test
joana;good

Error: ENOENT: no such file or directory, open 'albert;test
joana;good
'

and here is the csv file:

albert;test
joana;good

Could someone clarify what am I missing?

CodePudding user response：

The issue that you're currently experiencing is explained here

It appears that the first argument of createReadStream must be a file path, if you pass a Buffer, it simply calls .toString() to it.

CodePudding user response：

No need to work with the Buffer, which has no path. Using the FileInterceptor provides the file path, because you can store it in the diskStorage

@Post(':id/transactions/upload')
  @UseInterceptors(
    FileInterceptor('file', {
      storage: diskStorage({
        destination: '.files',
      }),
    }),
  )
  uploadTransactions(
    @Body() body: any,
    @UploadedFile() file: Express.Multer.File,
  ) {
    console.log('### file', file.path);
    return this.accountsUsersService.uploadTransactions(file);
  }