/
rows.go
148 lines (122 loc) · 3.6 KB
/
rows.go
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package basestore
import (
"database/sql"
)
// CloseRows closes the given rows object. The resulting error is a multierror
// containing the error parameter along with any errors that occur during scanning
// or closing the rows object. The rows object is assumed to be non-nil.
//
// The signature of this function allows scan methods to be written uniformly:
//
// func ScanThings(rows *sql.Rows, queryErr error) (_ []Thing, err error) {
// if queryErr != nil {
// return nil, queryErr
// }
// defer func() { err = CloseRows(rows, err) }()
//
// // read things from rows
// }
//
// Scan methods should be called directly with the results of `*store.Query` to
// ensure that the rows are always properly handled.
//
// things, err := ScanThings(store.Query(ctx, query))
func CloseRows(rows *sql.Rows, err error) error {
return combineErrors(err, rows.Close(), rows.Err())
}
// ScanStrings reads string values from the given row object.
func ScanStrings(rows *sql.Rows, queryErr error) (_ []string, err error) {
if queryErr != nil {
return nil, queryErr
}
defer func() { err = CloseRows(rows, err) }()
var values []string
for rows.Next() {
var value string
if err := rows.Scan(&value); err != nil {
return nil, err
}
values = append(values, value)
}
return values, nil
}
// ScanFirstString reads string values from the given row object and returns the first one.
// If no rows match the query, a false-valued flag is returned.
func ScanFirstString(rows *sql.Rows, queryErr error) (_ string, _ bool, err error) {
if queryErr != nil {
return "", false, queryErr
}
defer func() { err = CloseRows(rows, err) }()
if rows.Next() {
var value string
if err := rows.Scan(&value); err != nil {
return "", false, err
}
return value, true, nil
}
return "", false, nil
}
// ScanInts reads integer values from the given row object.
func ScanInts(rows *sql.Rows, queryErr error) (_ []int, err error) {
if queryErr != nil {
return nil, queryErr
}
defer func() { err = CloseRows(rows, err) }()
var values []int
for rows.Next() {
var value int
if err := rows.Scan(&value); err != nil {
return nil, err
}
values = append(values, value)
}
return values, nil
}
// ScanFirstInt reads integer values from the given row object and returns the first one.
// If no rows match the query, a false-valued flag is returned.
func ScanFirstInt(rows *sql.Rows, queryErr error) (_ int, _ bool, err error) {
if queryErr != nil {
return 0, false, queryErr
}
defer func() { err = CloseRows(rows, err) }()
if rows.Next() {
var value int
if err := rows.Scan(&value); err != nil {
return 0, false, err
}
return value, true, nil
}
return 0, false, nil
}
// ScanBools reads bool values from the given row object.
func ScanBools(rows *sql.Rows, queryErr error) (_ []bool, err error) {
if queryErr != nil {
return nil, queryErr
}
defer func() { err = CloseRows(rows, err) }()
var values []bool
for rows.Next() {
var value bool
if err := rows.Scan(&value); err != nil {
return nil, err
}
values = append(values, value)
}
return values, nil
}
// ScanFirstBool reads bool values from the given row object and returns the first one.
// If no rows match the query, a false-valued flag is returned.
func ScanFirstBool(rows *sql.Rows, queryErr error) (_ bool, _ bool, err error) {
if queryErr != nil {
return false, false, queryErr
}
defer func() { err = CloseRows(rows, err) }()
if rows.Next() {
var value bool
if err := rows.Scan(&value); err != nil {
return false, false, err
}
return value, true, nil
}
return false, false, nil
}