Collate multiple CSV into sheets in one Excel workbook using RubyXL

collate_excel.rb

files = Dir.glob("#{ENV["FOLDER"]}/**.csv").sort
files.each do |file|
  worksheet = workbook.add_worksheet(file.gsub("#{ENV["FOLDER"]}/", "").gsub(".csv", "").gsub("*", ""))
  row_indx = 0
  CSV.foreach(file) do |row|
    row.each_with_index do |cell, cell_indx|
      worksheet.add_cell(row_indx, cell_indx, cell)
    end
    row_indx += 1
  end
end

workbook.write("#{ENV["FOLDER"]}/collated.xlsx")