Setup database and Data directory

backend/setup_data_dir.go

@@ -0,0 +1,24 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+func setupDataDir() (string, error) {
+	var dataDir string
+	if os.Getenv("DATA_DIR") == "" {
+		dataDir = filepath.Join(".", "data")
+	} else {
+		dataDir = filepath.Join(".", os.Getenv("DATA_DIR"))
+	}
+
+	if _, err := os.Stat(dataDir); os.IsNotExist(err) {
+		err := os.Mkdir(dataDir, 0o755)
+		if err != nil {
+			return "", fmt.Errorf("cannot create '%s' directory: %w", dataDir, err)
+		}
+	}
+	return dataDir, nil
+}