Is there a way to set set config.action_controller.asset_host in development

Question

In my production.rb I set my asset_host to CloudFront like so:

config.action_controller.asset_host = 'http://xxxxxxxx.cloudfront.net'

Now I'm finding that in some circumstances (specifically, outputting JavaScript to be embedded into another site) I need to set the asset_host in the development environment too, the default null won't cut it. Ideally I want to set:

config.action_controller.asset_host = 'http://localhost:3000'

but this port can't be guaranteed, and I'm reluctant to hard-code it. Is there a way to set asset_host to the current domain and port?

Thanks!

score 8 · Accepted Answer · edited Jul 31 '16 at 14:04

8

You can make use of environment variables or Rails initializer parameters

config.action_controller.asset_host = ENV[ASSET_HOST].empty? ? 'http://' + Rails::Server.new.options[:Host] + ':' + Rails::Server.new.options[:Port] : ENV[ASSET_HOST]

This way if you set the environment variable you use that address otherwise it will use the default.

edited Jul 31 '16 at 14:04

Oscar Mederos

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answered May 17 '13 at 18:53

Paulo Fidalgo

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The Rails::Server.new.options hash was the answer I was looking for. Thanks! – superluminary May 20 '13 at 09:51
That's a useful hash to know about. – superluminary May 20 '13 at 09:56

score 4 · Answer 2 · answered Dec 29 '16 at 11:04

In Rails 4 we use a dynamic asset_host setting with a proc:

# in /config/environments/development.rb

Rails.application.configure do
  config.action_controller.asset_host = Proc.new { |source, request|
    # source = "/assets/brands/stockholm_logo_horizontal.png"
    # request = A full-fledged ActionDispatch::Request instance

    # sometimes request is nil and everything breaks
    scheme = request.try(:scheme).presence || "http"
    host = request.try(:host).presence || "localhost:3000"
    port = request.try(:port).presence || nil

    ["#{scheme}://#{host}", port].reject(&:blank?).join(":")
  }

  # more config
end

This code ensures that requests from localhost:3000, localhost:8080, 127.0.0.1:3000, local.dev and any other setup just work.

Thanks, this worked for fixing an issue I had with wanting to support both HTTP and HTTPS dev environments with the same configuration. — TimP, Mar 12 '21 at 08:41

score 3 · Answer 3 · edited May 23 '17 at 12:25

3

This value is available during startup and might help:

Rails::Server.new.options[:Port]

Try adding it to the asset_host variable of your development.rb file.

Based on this answer: https://stackoverflow.com/a/13839447/1882605

edited May 23 '17 at 12:25

Community

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answered May 17 '13 at 18:40

jbp

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score 0 · Answer 4 · answered May 17 '13 at 19:08

0

Try:

class ApplicationController < ActionController::Base
before_filter :find_asset_host

private

  def find_asset_host
    ActionController::Base.asset_host = Proc.new { |source|
        if Rails.env.development?
          "http://localhost:3000"
        else
          {}
        end
      }    
  end

answered May 17 '13 at 19:08

Firoz Ansari

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Cool, but still hardcoded. On the upside we have access to the request object in this context. – superluminary May 20 '13 at 09:50

Is there a way to set set config.action_controller.asset_host in development

4 Answers4