Fawce's notes on forking:

I'm forking the project to add support for streaming responses. Many of the csv files I'm generating are quite large, and need to be streamed rather than return in a single shot. I'm basing my stream handling on an example from David's Computer Stuff Journal

======== Important Note Though I did not write this code, I did convert it to a gem and I'm currently the sole owner on rubygems. With Joel Chippindale's approval I've taken over defacto maintainership of this gem. My use case is primarily under rails 3, and the current version is not backwards compatible, but I will maintain a 2.3.x branch as well if anyone has patches.

CSV Builder

The CSV Builder Rails plugin provides a simple templating system for serving dynamically generated CSV files from your application.

Requirements

The current version of CSV Builder works with:

Rails 3.x
Ruby 1.8 or 1.9

The legacy version (1.1.x) was originally developed and tested for Rails 2.1. See the legacy docs for more details.

Install

Install as a gem (recommended)

$ gem install csv_builder

If you are using Bundler then you know what to do.

Example

CSV template files are suffixed with .csv.csvbuilder, for example index.csv.csvbuilder

Add rows to your CSV file in the template by pushing arrays of columns into the csv object.

 # First row
 csv << [ 'cell 1', 'cell 2' ]
 # Second row
 csv << [ 'another cell value', 'and another' ]
 # etc...

You can set the default filename for that a browser will use for 'save as' by setting @filename instance variable in your controller's action method e.g.

@filename = 'report.csv'

You can set the input encoding and output encoding by setting @input_encoding and @output_encoding instance variables. These default to 'UTF-8' and 'LATIN1' respectively. e.g.

@output_encoding = 'UTF-8'

You can set @csv_options instance variable to define options for FasterCSV generator. For example:

@csv_options = { :force_quotes => true, :col_sep => ';' }

You can respond with csv in your controller as well:

respond_to do |format|
  format.html
  format.csv # make sure you have action_name.csv.csvbuilder template in place
end

You can also attach a csv file to mail sent out by your application by including a snippet like the following in your mailer method

attachment "text/csv" do |attachment|
  attachment.body = render(:file => 'example/index.csv.csvbuilder')
  attachment.filename = 'report.csv'
end

Contributions

As of version 2.0 this gem has a rudimentary spec suite for Rails 3. The test suite has been run under both Ruby 1.8 and 1.9. The requirements are in the Gemfile within the test spec directory. You will need Bundler installed and then you can run:

cd spec/rails_app && bundle install && cd ../..

To install the main testing requirements. Then return back to the root directory and run:

rake spec

I will also take patches for Rails 2.3.x, though I personally have no further need of that branch.

Troubleshooting

There's a known bug of encoding error in Ruby 1.9

For more details see https://rails.lighthouseapp.com/projects/8994/tickets/2188-i18n-fails-with-multibyte-strings-in-ruby-19-similar-to-2038