Feat: ReadSheet implemented

fetch-sheet.go

@@ -0,0 +1,32 @@
+package rota
+
+import (
+	"context"
+	"fmt"
+
+	"google.golang.org/api/option"
+	"google.golang.org/api/sheets/v4"
+)
+
+// ReadRota czyta zadany zakres z arkusza i zwraca wiersze.
+// spreadsheetID to ID z URL-a arkusza, readRange np. "Dyżury!A1:C30".
+func ReadSheet(ctx context.Context, credsPath, spreadsheetID, readRange string) ([][]interface{}, error) {
+	srv, err := sheets.NewService(ctx,
+	  option.WithAuthCredentialsFile(option.ServiceAccount, credsPath),
+	  option.WithScopes(sheets.SpreadsheetsReadonlyScope),
+  )
+	if err != nil {
+		return nil, fmt.Errorf("init sheets service: %w", err)
+	}
+
+	resp, err := srv.Spreadsheets.Values.
+		Get(spreadsheetID, readRange).
+		ValueRenderOption("UNFORMATTED_VALUE"). // surowe wartości, bez formatowania komórek
+		Context(ctx).
+		Do()
+	if err != nil {
+		return nil, fmt.Errorf("get values %q: %w", readRange, err)
+	}
+
+	return resp.Values, nil
+}