improve handling of empty data

cmd/main/main.go

@@ -156,6 +156,24 @@ func main() {
 	if len(vslice) < 1 {
 		// There was no data but lets just log that and close off the empty workbook
 		fmt.Printf("No data found contained in top-level json key '%s', no work to do.\n", parentNode)
+
+		// Create new file
+		xlsx = createWorkbook(worksheetName, outputFilename)
+
+		// Run code to add column names to the first row of the workbook based off the keyOrder, if defined
+		if len(config.keyOrder) > 0 {
+
+			// Create a slice to hold the values
+			var columnHeadings []string
+
+			// Iterate over the map and append each value to the slice
+			for _, value := range config.keyOrder {
+				columnHeadings = append(columnHeadings, value)
+			}
+
+			createHeadingRow(xlsx, worksheetName, columnHeadings)
+		}
+
 		// Close off the file
 		if err := xlsx.SaveAs(outputFilename); err != nil {
 			log.Fatal(err)