Question

I am not sure how to configure the environment such that Carrier Wave will use the local file storage when running the app locally (development) and s3 after i load to heroku (production)

in Development storage :file

in Production storage :s3

Answer 1

Either model, or you can set it globally. Have a look at the readme for v0.5.2 (current gem) at https://github.com/jnicklas/carrierwave/tree/v0.5.2

Near the bottom, there are some instructions for configuring the test environment. Use the same approach to use different configurations for “development” and “production”, e.g. add a file “carrierwave.rb” to “config/initialisers” and add the configuration code

if Rails.env.test? or Rails.env.cucumber?
  CarrierWave.configure do |config|
    config.storage = :file
    config.enable_processing = false
  end
end

and for development

if Rails.env.development?
  CarrierWave.configure do |config|
    config.storage = :file
  end
end

and production

if Rails.env.production?
  CarrierWave.configure do |config|
    config.storage = :s3
  end
end