add basic demo data

internal/db/init.go

@@ -11,7 +11,7 @@ import (
 	"git.artlef.fr/PersonalLibraryManager/internal/model"
 )
 
-func Initdb(databaseDir string) *gorm.DB {
+func Initdb(databaseDir string, demoDataPath string) *gorm.DB {
 	createDbFolderIfMissing(databaseDir)
 	db, err := gorm.Open(
 		sqlite.Open(
@@ -22,9 +22,23 @@ func Initdb(databaseDir string) *gorm.DB {
 	}
 	// Migrate the schema
 	db.AutoMigrate(&model.Book{})
+	var book model.Book
+	queryResult := db.Limit(1).Find(&book)
+	if queryResult.RowsAffected == 0 && demoDataPath != "" {
+		migrateSchema(db, demoDataPath)
+	}
 	return db
 }
 
+func migrateSchema(db *gorm.DB, demoDataPath string) {
+	log.Printf("Loading demo data file %s\n", demoDataPath)
+	data, err := os.ReadFile(demoDataPath)
+	if err != nil {
+		log.Fatal(err)
+	}
+	db.Exec(string(data))
+}
+
 func createDbFolderIfMissing(databaseDir string) {
 	_, openFileErr := os.Open(databaseDir)
 	if os.IsNotExist(openFileErr) {