Rails 4.0 PG::UnableToSend socket not open

Question

I'm currently trying to upgrade a Rails 3.2 app to Rails 4.0.13 (ruby 2.3.5, PostgreSQL 9.4.13) and I'm getting this error when running my integration tests;

      :  PG::UnableToSend at /companies/get_current_firm
      : ===============================================
      : 
      : > socket not open
      : 
      : 
      : activerecord (4.0.13) lib/active_record/connection_adapters/postgresql_adapter.rb, line 798
      : -------------------------------------------------------------------------------------------
      : 
      : ``` ruby
      :   793           end
      :   794   
      :   795           FEATURE_NOT_SUPPORTED = "0A000" #:nodoc:
      :   796   
      :   797           def exec_no_cache(sql, binds)
      : > 798             @connection.async_exec(sql, [])
      :   799           end
      :   800   
      :   801           def exec_cache(sql, binds)
      :   802             stmt_key = prepare_statement sql
      :   803   
      : ```

This integration test logs in and then there is a number of calls from the frontend (AngularJS) to get details like the current firm selected, etc. Each one of these calls gets the same message, it's like the connection has been shutdown. I'm using the chrome browser through selenium & capybara in LIVE mode so I can see what is happening.

Here is my database.yml file for test

test: &test
  adapter: postgresql
  encoding: unicode
  database: test_<%= ENV['USER'] %><%= ENV['TEST_ENV_NUMBER'] %>
  pool: 5
  username: <%= ENV['DATABASE_USER'] %>
  password: <%= ENV['DATABASE_PASSWORD'] %>

Here is the call it is making from the frontend

AngularJS

  current_firm: (scope) ->
    $http({method: 'GET', url: '/companies/get_current_firm'}).success (data) ->
      scope.current_firm = data['firm']

Rails Controller

  def get_current_firm
    render json: {firm: current_firm.organisation}
  end

There are three separate calls to get different data when a user logs in, sometimes in the tests it will get 1 or 2 of them but never three.

I tried the work around from http://www.ruby-railings.com/en/rails/postgresql/2014/01/11/connection-problems-in-rails-4.html. This didn't fix the problem at all.

Update

When the user logs in there are three http calls fired off from AngularJS to the Rails backend. If I remark out two of the calls then that call works every time. If I remark out only one, so we have two calls then it fails one or both of the calls. I get a 'pending' message on one of the calls.

Answer 1

I've worked that this was an AngularJS problem sending too many requests to Rails 4 at once. To fix the problem I put each call in a promise.