Excelinator

Small gem for generating real Excel spreadsheets from existing CSV data and HTML tables that fully supports UTF-8 characters.

Why?

Well, when you're starting up and things are small and then things grow and then people want reports and they'd like them in Excel most of the time and then you realize you can just throw some cheap CSV views at them and Excel will be fine with them and then you get even bigger and you start getting, like, friggin' international and then the French dudes are like, "My umlauts look like chewed croissant" and you try prefixing your CSV with a UTF-8 BOM and that makes some Excels happy (Windows) but not others (Mac) and you think man I totally want to just, y'know, eat the croissant like it was meant to be eaten y'know? and there's a zillion spreadsheet gems out there already except they all like merge back to that one spreadsheet gem, and you could go XMLDoc maybe, but then it's just like lemme use the CSV I've already got and try to not make me work much?

No Rails Required

The heart of this gem has a couple of small methods to handle the transformations. If that's all you need, you're good to go.

CSV

Call Excelinator.csv_to_xls(csv_content). The csv_content will be parsed by FasterCSV and converted to Excel spreadsheet contents ready to be saved to file or sent across the wire.

HTML

Call Excelinator.html_as_xls(html_content). The table element from the HTML content is extracted, a meta tag indicating utf-8 encoding is prepended and that's it. The resulting content isn't actually an Excel spreadsheet, just the HTML data. But write this out to a file with an .xls extension and Excel will open the contents and translate the <table> for you, formatting and all.

NOTE: While some spreadsheet programs (e.g. Google Docs) will not translate HTML tables like this, both Excel on Windows and Mac will as well as OpenOffice.

But I Need Rails

As you wish. As always, TMTOWTDI, but here are a few usage options. All examples work in Rails 2 and 3, except where noted.

If you want to make an explicit xls view that has CSV content in it:

class FooController < ApplicationController
  def report
    respond_to do |format|
      format.html
      format.csv
      format.xls { render :xls => 'foo_report.xls' }
    end
  end
end

Rails 2 doesn't support custom renderers, but the guts of our :xls renderer are mixed into the controllers, so you can call it directly this way:

      format.xls { send_xls_data 'foo_report.xls' }

If you want to re-use an existing HTML view:

      format.xls { send_xls_data 'foo_report.xls', :file => 'foo/report.html.erb' }

:template also works in place of :file in Rails 3. render :xls => also works in place of send_xls_data in Rails 3.

Also note, send_xls_data (the guts of render :xls) will parse the given content and detect CSV or HTML, so no need to specify which is being passed in.

You can even go with just an explicit xls view and no controller code, but you'll need to convert the CSV content yourself inside the view:

<%= Excelinator.csv_to_xls(render :file => 'foo/xls_view.csv.erb').html_safe %>

:template works in place of :file here as well in Rails 3.

Or ... refactor the CSV content to a format-less partial:

# _report.erb
<%= generate_csv_report %>

# report.csv.erb
<%= render :partial => 'report' %>

# report.xls.erb
<%= Excelinator.csv_to_xls(render :partial => 'report').html_safe %>

There are test apps included in the source repo that exercise these different options.

FAQ

You lied when you said "real Excel spreadsheets from ... HTML tables." What about converting HTML tables to a real Excel file?

I did, and I apologize. Lemme know when your pull request is ready.

Are there any options to re-use CSV/HTML views with No additional controller/view code?

I've tinkered with it, but it requires a bit of duck punching of the Rails rendering code.

What if I want to generate a real Excel spreadsheet from scratch with all sorts of awesome in it?

This gem uses spreadsheet under the covers. There are also others that support a wide variety of Excel features:

With any of these, you can create specific .xls views and have them use the classes in these gems that let you define a Workbook with multiple Worksheets with rows and columns of formatted formulas.

For support higher up the ladder within Rails and/or ActiveRecord, here are a few options I've found, though I can't vouch for any. Search rubygems and github for 'spreadsheet' 'excel' and 'xls' and you'll find lots of additional projects. Most appear to use either the above Spreadsheet gem or generate XMLDoc.

They're not all supposed to work. Think of it more as a workshop for example code.