add a link to the upgrading docs in the error message

Fixes #1854

Signed-off-by: Nicola Murino <nicola.murino@gmail.com>

internal/dataprovider/bolt.go

@@ -3181,7 +3181,7 @@ func (p *BoltProvider) migrateDatabase() error {
 		providerLog(logger.LevelDebug, "bolt database is up to date, current version: %d", version)
 		return ErrNoInitRequired
 	case version < 29:
-		err = fmt.Errorf("database schema version %d is too old, please see the upgrading docs", version)
+		err = errSchemaVersionTooOld(version)
 		providerLog(logger.LevelError, "%v", err)
 		logger.ErrorToConsole("%v", err)
 		return err

internal/dataprovider/dataprovider.go

@@ -4688,6 +4688,10 @@ func checkReservedUsernames(username string) error {
 	return nil
 }
 
+func errSchemaVersionTooOld(version int) error {
+	return fmt.Errorf("database schema version %d is too old, please see the upgrading docs: https://docs.sftpgo.com/latest/data-provider/#upgrading", version)
+}
+
 func providerLog(level logger.LogLevel, format string, v ...any) {
 	logger.Log(level, logSender, "", format, v...)
 }

internal/dataprovider/mysql.go

@@ -798,7 +798,7 @@ func (p *MySQLProvider) migrateDatabase() error {
 		providerLog(logger.LevelDebug, "sql database is up to date, current version: %d", version)
 		return ErrNoInitRequired
 	case version < 29:
-		err = fmt.Errorf("database schema version %d is too old, please see the upgrading docs", version)
+		err = errSchemaVersionTooOld(version)
 		providerLog(logger.LevelError, "%v", err)
 		logger.ErrorToConsole("%v", err)
 		return err

internal/dataprovider/pgsql.go

@@ -822,7 +822,7 @@ func (p *PGSQLProvider) migrateDatabase() error { //nolint:dupl
 		providerLog(logger.LevelDebug, "sql database is up to date, current version: %d", version)
 		return ErrNoInitRequired
 	case version < 29:
-		err = fmt.Errorf("database schema version %d is too old, please see the upgrading docs", version)
+		err = errSchemaVersionTooOld(version)
 		providerLog(logger.LevelError, "%v", err)
 		logger.ErrorToConsole("%v", err)
 		return err

internal/dataprovider/sqlite.go

@@ -718,7 +718,7 @@ func (p *SQLiteProvider) migrateDatabase() error { //nolint:dupl
 		providerLog(logger.LevelDebug, "sql database is up to date, current version: %d", version)
 		return ErrNoInitRequired
 	case version < 29:
-		err = fmt.Errorf("database schema version %d is too old, please see the upgrading docs", version)
+		err = errSchemaVersionTooOld(version)
 		providerLog(logger.LevelError, "%v", err)
 		logger.ErrorToConsole("%v", err)
 		return err