Vanity not using Redis to Go server on Heroku

Question

I've recently deployed some A/B testing experiments using vanity to my heroku instance. However, whenever I access the dashboard i.e. /vanity The following error shows up in the logs

- ActionView::Template::Error (Connection refused - Unable to connect to Redis on 127.0.0.1:6379):
-     1: <ul class="experiments">
-     2:   <% experiments.sort_by { |id, experiment| experiment.created_at }.reverse.each do |id, experiment| %>
-     3:     <li class="experiment <%= experiment.type %>" id="experiment_<%=vanity_h id.to_s %>">
-     4:     <%= render :file => Vanity.template("_experiment"), :locals => { :id => id, :experiment => experiment } %>
-     5:     </li>
-   

However, the redis to go url seems to be set up correctly and vanity seems to be able to access it e.g.

irb(main):011:0> Vanity.playground.connection
=> redis://bluegill.redistogo.com:9231/0

Anyone know what I could be doing wrong ?

 my vanity.rb config file is fairly standard

    development:
      adapter: redis
      connection: redis://localhost:6379/0
    qa:
      adapter: redis
      connection: <%= ENV["REDISTOGO_URL"] %>
    staging:
      adapter: redis
      connection: <%= ENV["REDISTOGO_URL"] %>
    production:
      adapter: redis
      connection: <%= ENV["REDISTOGO_URL"] %>

and also the ENV["REDISTOGO_URL"] seems correct

irb(main):012:0> ENV["REDISTOGO_URL"]
=> "redis://redistogo:[email protected]:9231/"

And I can access Redis from the rest of the app, it just seems that Vanity is not picking it up for this template..

Answer 1

Ok, I've figured this one out. When we fork with unicorn I wasn't reconnecting to the correct redis server and instead defaulting to the localhost. This code snippet in unicorn.rb sorts it out.

after_fork do |server, worker|
  # the following is *required* for Rails + "preload_app true",
  ActiveRecord::Base.establish_connection
  Vanity.playground.establish_connection(ENV["REDISTOGO_URL"]) 
end

I'm sure its similar for other forking servers too.