model: Require same version for executable and DB

Currently only an empty database and an existing database with the same
version are supported.

Support for migrations based on semantic versioning will be added in
future versions of Ceres.

1 files changed, 29 insertions, 0 deletions

diff --git a/model/database.go b/model/database.go
index 8e002d6..b6e64bb 100644
--- a/model/database.go
+++ b/model/database.go
@@ -93,6 +93,26 @@ VALUES
 	return err
 }
 
+func getDatabaseVersion(tx *sql.Tx) string {
+	rows, err := tx.Query(`SELECT value FROM metadata WHERE key='version';`)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer rows.Close()
+
+	if !rows.Next() {
+		log.Fatalf("No rows on request of database version")
+	}
+
+	var version string
+	err = rows.Scan(&version)
+	if err != nil {
+		log.Fatalf("Failed to scan database version to string")
+	}
+
+	return version
+}
+
 func MigrateDatabase(version string) {
 	err := Transaction(func(tx *sql.Tx) error {
 		if isDatabaseEmpty(tx) {
@@ -113,6 +133,15 @@ func MigrateDatabase(version string) {
 			}
 		}
 
+		dbVersion := getDatabaseVersion(tx)
+		if dbVersion != version {
+			log.Fatalf(
+				"Database version '%s' does not match executable version '%s'",
+				dbVersion,
+				version,
+			)
+		}
+
 		return nil
 	})
 	if err != nil {