Simple .xlsx to .yml file converter

converter.rb

require 'roo'
require 'yaml'

class Converter
  def initialize(input_path, output_path)
    @input_path = input_path
    @output_path = output_path
  end

  def convert
    xlsx = Roo::Spreadsheet.open(@input_path)
    sheet = xlsx.sheet(0)
    headers = sheet.row(1)
    data = (2..sheet.last_row).map do |i|
      row = Hash[headers.zip(sheet.row(i))]
      transformed_row = transform_row(row)
      next if transformed_row[row['Resource']][row['Action']][row['Role']].include?("none")
      transformed_row
    end.compact

    # Deep merge all the hashes into one
    data = deep_merge_hashes(*data)
    # Generate YAML without document separator
    yaml_data = data.to_yaml(lines: {chomp: true})

    yaml_data = yaml_data.lines.map do |line|
      next if line.start_with?("---\n")
      if line.include?("- all")
        line.gsub!('all', ':all')
      elsif line.include?(" is_")
        line.gsub!('is_', ':')
        line = "#{line.chomp}?\n"
      elsif !line.include?(":")
        line = "#{line.chomp}?\n"
      end

      if line.strip.start_with?('-')
        '  ' + line
      else
        line
      end
    end

    yaml_data = yaml_data.join

    yaml_data.slice!(0, 4) if yaml_data.start_with?("---\n") # Remove "---\n" at the start

    File.open(@output_path, 'w') { |f| f.write(yaml_data) }
  end

  def deep_merge_hashes(*hashes)
    hashes.inject do |merged, hash|
      merged.merge(hash) do |key, old_val, new_val|
        if old_val.is_a?(Hash) && new_val.is_a?(Hash)
          deep_merge_hashes(old_val, new_val)
        else
          [*old_val, *new_val]
        end
      end
    end
  end

  private

  def transform_row(row)
    {
      row['Resource'] => {
        row['Action'] => {
          row['Role'] => row['Rule'] ? [row['Rule']] : []
        }
      }
    }
  end
end

Gemfile

source "https://rubygems.org"

gem "roo"

main.rb

require_relative 'converter'

excel_converter = Converter.new('permissions.xlsx', 'permissions.yml')
excel_converter.convert