Parse CSV file from API request in go-kit golang

Question

I am trying to build a service that takes user input of file from POST request and then iterates the CSV and passes it into my database. I am having problem to pass the file and read it. Below are my codes.

Endpoint.go

  type CSVRequest struct {
    File  io.Reader

}


func MakeCSVEndpoint(svc Service) endpoint.Endpoint {
    return func(ctx context.Context, request interface{}) (interface{}, error) {
        req := request.(CSVRequest)

        data, err := svc.ReadCSV(req.File)

        if err != nil {
            return GetErrorResponse{err}, nil
        }

        return CreateProductResponse{data}, nil
    }
}

transport.go

    func decodeCreateProductsCSV(_ context.Context, r *http.Request) (interface{}, error) {
    file, _, err := r.FormFile("file")

    return CSVRequest{File: file}, nil
}

so how can I pass the csv file to the service.go and then read and iterate the csv file and get the values of the csv file.

Answer 1

Here is a basic function that can do the parsing from a POST request. The result is a two-dimensional array of strings, the first dimension being the rows and the second dimension being the values in a row. It uses the golang's own "encoding/csv" package. Go playground example available here.

func ReadCSVFromHttpRequest(req *http.Request) ([][]string, error) {
    // parse POST body as csv
    reader := csv.NewReader(req.Body)
    var results [][]string
    for {
        // read one row from csv
        record, err := reader.Read()
        if err == io.EOF {
            break
        }
        if err != nil {
            return nil, err
        }

        // add record to result set
        results = append(results, record)
    }
    return results, nil
}