mysqlite/migrator.go

88 lines
2.2 KiB
Go

package mysqlite
import (
"database/sql"
"embed"
"fmt"
"io/fs"
"log"
"strconv"
"strings"
"zombiezen.com/go/sqlite"
)
type ReadDirFileFS interface {
fs.ReadDirFS
fs.ReadFileFS
}
func (db *Db) MigrateDb(migrations ReadDirFileFS) error {
// Read all migrations
migrationFiles, err := migrations.ReadDir("")
if err != nil {
log.Fatalf("error reading migration files: %v", err)
}
var migrationsByVersion = make(map[int]string)
latestVersion := 0
for _, f := range migrationFiles {
versionStr := f.Name()
version, err := strconv.Atoi(strings.SplitN(versionStr, "_", 2)[0])
if err != nil {
log.Fatalf("invalid version number for migration script: %v", err)
}
migrationsByVersion[version] = versionStr
latestVersion = max(latestVersion, version)
}
// Get current migration version from user_version
var currentVersion int
err = d.QuerySingle("PRAGMA user_version", &currentVersion)
if err != nil {
log.Fatalf("error getting current version: %v", err)
}
log.Printf("Current database migration version is %d, latest version is %d", currentVersion, latestVersion)
// If we are no up-to-date, bring the db up-to-date
for currentVersion != latestVersion {
targetVersion := currentVersion + 1
migrationFile := migrationsByVersion[targetVersion]
log.Printf("migration to version %s", migrationFile)
migrationScript, err := migrations.ReadFile(migrationFile)
if err != nil {
log.Fatalf("error opening migration script %s: %v", migrationScript, err)
}
tx, err := db.Begin()
if err != nil {
log.Fatalf("error beginning transaction: %v", err)
}
defer tx.MustRollback()
err = tx.QuerySingle(string(migrationScript))
if err != nil {
log.Fatalf("error performing migration: %v", err)
}
err = tx.QuerySingle(fmt.Sprintf("PRAGMA user_version = %d", targetVersion))
if err != nil {
log.Fatalf("error updating version: %v", err)
}
err = tx.Commit()
if err != nil {
log.Fatalf("error commiting transaction: %v", err)
}
currentVersion = targetVersion
}
log.Println("All migrations applied")
return nil
}
func rollbackIgnoringErrors(tx *sql.Tx) {
err := tx.Rollback()
if err != nil {
log.Printf("error rolling back: %v", err)
}
}