ThrottledCsv

this plugin hopes to extract out several key features of exporting db data to csv that seemed to be needed.

heavily inspired by Andrew Timberlake http://ramblingsonrails.com/download-a-large-amount-of-data-in-csv-from-rails

throttled - it will download as it's generated to mitigate memory usage for large datasets dynamic fields - will allow for attributes as well as methods, pick and choose what you want the columns to be black-box - now it's simply a method you define an options hash for in the controller, making it trivial to add future csv exports

Options

:db_table - name of primary database table with the data :label - will be concatenated with datetime for resulting filename :include - used for joins with main model, use just like activerecord :scope - AR model with scopes used as the basis for an AR find :fields - array of columns to export in csv. Can use association or custom methods :header (optional)- labels for top header row of csv, can be anything you want.
If not defined will autofill with humanized version of :fields.

Example

using the following db tables:

create_table "users", :force => true do |t| t.string "email" t.string "crypted_password", :limit => 40 t.string "salt", :limit => 40 t.datetime "created_at" t.datetime "updated_at" t.integer "country_id" t.string "nickname" t.string "first_name" t.string "last_name" end

create_table "countries", :force => true do |t| t.string "name" end

your controller action will look like thus:

def users @users = User.all respond_to do |format| format.html format.csv do options = { :db_table => "users", :label => "user_export", :include => [:country], :scope => @users, :fields => ["id","nickname","email","first_name","last_name","country.name","created_at"], :header => ["ID","Nickname","Email","First Name","Last Name","Country","Created At"] } render_to_csv(options) end end end

Copyright (c) 2010 Ethan Burrow, released under the MIT license