I’m pleased to announce the new Excel Export plugin for Ruby on Rails. This plugin allows Rails developers to easily export their data to an Excel spreadsheet.

To install via SubVersion,

ruby script/plugin install http://svn.napcsweb.com/public/excel

Simple example

Let’s assume we have two models… a Project and a Task. A Project has_many :tasks. In one of our controllers, we can create the following method which will stream a new Microsoft Excel document to the client’s browser.

  def export_project_to_excel<br />
    e = Excel::Workbook.new<br />
    @project = Project.find(:all)<br />
    @tasks = @project.tasks<br />
    e.addWorksheetFromActiveRecord "Project", "project", @project<br />
    e.addWorksheetFromActiveRecord "Tasks", "task", @tasks<br />
    headers['Content-Type'] = "application/vnd.ms-excel"<br />
    render_text(e.build)<br />
  end

More Advanced example

This time, let’s create an array of hashes. This way, we can manipulate our data ourselves, instead of letting the plugin do the mapping. This is really useful when you have “has_many” or “belongs to” relationships and you want to export meaningful values instead of the foreign keys.

  def export_book_info_to_excel
    e = Excel::Workbook.new
    books = Book.find(:all)
    array = Array.new
    for book in books
      item = Hash.new
      item["Title"] = book.title
      item["ISBN"] = book.isbn
      item["Author"] = book.author.last_name
      item["Category"] = book.category.name
      item["Total Sales"] = book.sales.size
      array << item
    end
    e.addWorksheetFromArrayOfHashes("Books info", array)<br />
    headers['Content-Type'] = "application/vnd.ms-excel"<br />
    render_text(e.build)<br />
  end