harness-drone/server/datastore/migrate/version.go
2014-09-28 20:21:02 -07:00

57 lines
1.6 KiB
Go

package migrate
import (
"github.com/BurntSushi/migration"
)
// GetVersion gets the migration version from the database,
// creating the migration table if it does not already exist.
func GetVersion(tx migration.LimitedTx) (int, error) {
v, err := getVersion(tx)
if err != nil {
if err := createVersionTable(tx); err != nil {
return 0, err
}
return getVersion(tx)
}
return v, nil
}
// SetVersion sets the migration version in the database,
// creating the migration table if it does not already exist.
func SetVersion(tx migration.LimitedTx, version int) error {
if err := setVersion(tx, version); err != nil {
if err := createVersionTable(tx); err != nil {
return err
}
return setVersion(tx, version)
}
return nil
}
// setVersion updates the migration version in the database.
func setVersion(tx migration.LimitedTx, version int) error {
_, err := tx.Exec(rebind("UPDATE migration_version SET version = ?"), version)
return err
}
// getVersion gets the migration version in the database.
func getVersion(tx migration.LimitedTx) (int, error) {
var version int
row := tx.QueryRow("SELECT version FROM migration_version")
if err := row.Scan(&version); err != nil {
return 0, err
}
return version, nil
}
// createVersionTable creates the version table and inserts the
// initial value (0) into the database.
func createVersionTable(tx migration.LimitedTx) error {
_, err := tx.Exec("CREATE TABLE migration_version ( version INTEGER )")
if err != nil {
return err
}
_, err = tx.Exec("INSERT INTO migration_version (version) VALUES (0)")
return err
}