/* * Minio Cloud Storage, (C) 2019 Minio, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package csv import ( "bytes" "encoding/csv" "fmt" "github.com/minio/minio/pkg/s3select/sql" "github.com/tidwall/sjson" ) // Record - is CSV record. type Record struct { columnNames []string csvRecord []string nameIndexMap map[string]int64 } // Get - gets the value for a column name. CSV fields do not have any // defined type (other than the default string). So this function // always returns fields using sql.FromBytes so that the type // specified/implied by the query can be used, or can be automatically // converted based on the query. func (r *Record) Get(name string) (*sql.Value, error) { index, found := r.nameIndexMap[name] if !found { return nil, fmt.Errorf("column %v not found", name) } if index >= int64(len(r.csvRecord)) { // No value found for column 'name', hence return null // value return sql.FromNull(), nil } return sql.FromBytes([]byte(r.csvRecord[index])), nil } // Set - sets the value for a column name. func (r *Record) Set(name string, value *sql.Value) error { r.columnNames = append(r.columnNames, name) r.csvRecord = append(r.csvRecord, value.CSVString()) return nil } // MarshalCSV - encodes to CSV data. func (r *Record) MarshalCSV(fieldDelimiter rune) ([]byte, error) { buf := new(bytes.Buffer) w := csv.NewWriter(buf) w.Comma = fieldDelimiter if err := w.Write(r.csvRecord); err != nil { return nil, err } w.Flush() if err := w.Error(); err != nil { return nil, err } data := buf.Bytes() return data[:len(data)-1], nil } // MarshalJSON - encodes to JSON data. func (r *Record) MarshalJSON() ([]byte, error) { data := "{}" var err error for i := len(r.columnNames) - 1; i >= 0; i-- { if i >= len(r.csvRecord) { continue } if data, err = sjson.Set(data, r.columnNames[i], r.csvRecord[i]); err != nil { return nil, err } } return []byte(data), nil } // NewRecord - creates new CSV record. func NewRecord() *Record { return &Record{} }