I've been reading similar questions, but many of the answers are outdated or not clear enough for me.

I'd like to be able to just do something like (in a controller action):

respond_to do |format|
  format.html
  format.csv
end

I know I'd then need a view such as action.csv.erb

---

So my questions are:

1) What do I need to configure in rails to allow this to happen in general.

2) How should I setup the CSV view to display some basic fields from a model?

UPDATE:

So I've tried to go the route of comma, I installed and vendored the gem.

Then according to the read me, I threw this into my model (customized to my needs):

comma do

user_id 'User'
created_at 'Date'
name 'Name'
end

I then threw this in the control for the index action (according to the readme):

  format.csv { render :csv => MyModel.limited(50) }

Then when accessing the index (not in CSV format) I receive the following ActionController Exception error:

undefined method `comma' for

So then I googled that, and I read that I should put require 'comma' in my model.

After开发者_如何学C doing that, I refreshed (my local index page), and the error changed to:

no such file to load -- comma

So at this point I decided it must not be finding the comma files obviously. So I copied the files from the vendored gem folder of comma, from comma's lib folder, to the rails lib folder. I then refreshed the page and landed on this error:

uninitialized constant Error

Then I pretty much gave up.

The errors from the trace were:

/Users/elliot/.gem/ruby/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:443:in load_missing_constant' /Users/elliot/.gem/ruby/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:80:in const_missing' /Users/elliot/.gem/ruby/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:92:in `const_missing'

Other notes, I have already installed FasterCSV

Hope thats enough info :)

---

I suggest taking a look at comma. It works very well and allows you to handle stuff at the model level, as opposed to the view level.

---

Have a look at FasterCSV.

csv_string = FasterCSV.generate do |csv|

  cols = ["column one", "column two", "column three"]

  csv << cols

  @entries.each do |entry|                
    csv << [entry.column_one, entry.column_two, entry.column_three ]
  end

  filename = "data-#{Time.now.to_date.to_s}.csv"    

end

send_data(csv_string, :type => 'text/csv; charset=utf-8; header=present', :filename => filename)  

---

This is terrible, but the CSV library (in 1.9, == FasterCSV) won't play nice with meta_where, so I did it this way:

@customers.collect {|c| lines.push ["#{c.lastname}","#{c.firstname}","#{c.id}","#{c.type}"}
lines = lines.collect {|line| line.join(',')}
csv_string = lines.join("\n")  
respond_to do |format|
  format.html
  format.csv { send_data(csv_string, :filename => "#{@plan.name.camelize}.csv", :type => "text/csv") }
end

It's ugly, but effective.

---

Take a look at CSV Shaper.

https://github.com/paulspringett/csv_shaper

It has a nice DSL and works really well with Rails models.