Validate changes made to database.yml

database_config_testing.rb

# To validate the changes I made to database config I ran the following under Rails console
original   = YAML.load(ERB.new(File.read("#{Rails.root}/config/database.yml")).result)   
new_config = YAML.load(ERB.new(File.read("#{Rails.root}/config/database_new.yml")).result)   

# require 'pp'
# pp original ->
{"local"=>
  {"adapter"=>"mysql2",
   "encoding"=>"utf8",
   "database"=>"connect",
   "username"=>"root",
   "password"=>"development"},
 "test"=>
  {"adapter"=>"mysql2",
   "encoding"=>"utf8",
   "database"=>"connect_test",
   "username"=>"root",
   "password"=>"development"},
 "dev"=>
  {"adapter"=>"mysql2",
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "encoding"=>"utf8",
   "database"=>"connect_dev",
   "username"=>"connect_dev",
   "password"=>nil,
   "host"=>"connect-preprod.c90ubbnnizhv.us-west-2.rds.amazonaws.com",
   "port"=>3306},
 "testing"=>
  {"adapter"=>"mysql2",
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "encoding"=>"utf8",
   "database"=>"connect",
   "username"=>"connect_testing",
   "password"=>nil,
   "host"=>"connect-testing.c90ubbnnizhv.us-west-2.rds.amazonaws.com",
   "port"=>3306},
 "staging"=>
  {"adapter"=>"mysql2",
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "encoding"=>"utf8",
   "database"=>"connect",
   "username"=>"connect_staging",
   "password"=>nil,
   "host"=>"connect-staging.c90ubbnnizhv.us-west-2.rds.amazonaws.com",
   "port"=>3306},
 "demo"=>
  {"adapter"=>"mysql2",
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "encoding"=>"utf8",
   "database"=>"connect_demo",
   "username"=>"connect_demo",
   "password"=>nil,
   "host"=>"connect-staging.c90ubbnnizhv.us-west-2.rds.amazonaws.com",
   "port"=>3306},
 "integration"=>
  {"adapter"=>"mysql2",
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "encoding"=>"utf8",
   "database"=>"connect",
   "username"=>"connect_int",
   "password"=>nil,
   "host"=>"connect-integration.c90ubbnnizhv.us-west-2.rds.amazonaws.com",
   "port"=>3306},
 "preproduction"=>
  {"adapter"=>"mysql2",
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "encoding"=>"utf8",
   "database"=>"connect",
   "username"=>"connect_preprod",
   "password"=>nil,
   "host"=>"connect-preprod.c90ubbnnizhv.us-west-2.rds.amazonaws.com",
   "port"=>3306},
 "production"=>
  {"adapter"=>"mysql2",
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "encoding"=>"utf8",
   "database"=>"connect",
   "username"=>"connect_prod",
   "password"=>nil,
   "host"=>"connect.c90ubbnnizhv.us-west-2.rds.amazonaws.com",
   "port"=>3306}}

# require 'pp'
# pp new_config ->
{"local"=>
  {"adapter"=>"mysql2",
   "database"=>"connect",
   "encoding"=>"utf8",
   "port"=>3306,
   "username"=>"root",
   "password"=>nil},
 "test"=>
  {"adapter"=>"mysql2",
   "database"=>"connect_test",
   "encoding"=>"utf8",
   "port"=>3306,
   "username"=>"root",
   "password"=>nil},
 "dev"=>
  {"adapter"=>"mysql2",
   "database"=>"connect_dev",
   "encoding"=>"utf8",
   "port"=>3306,
   "username"=>"connect_dev",
   "password"=>nil,
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "host"=>"connect-preprod.c90ubbnnizhv.us-west-2.rds.amazonaws.com"},
 "testing"=>
  {"adapter"=>"mysql2",
   "database"=>"connect",
   "encoding"=>"utf8",
   "port"=>3306,
   "username"=>"connect_testing",
   "password"=>nil,
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "host"=>"connect-testing.c90ubbnnizhv.us-west-2.rds.amazonaws.com"},
 "staging"=>
  {"adapter"=>"mysql2",
   "database"=>"connect",
   "encoding"=>"utf8",
   "port"=>3306,
   "username"=>"connect_staging",
   "password"=>nil,
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "host"=>"connect-staging.c90ubbnnizhv.us-west-2.rds.amazonaws.com"},
 "demo"=>
  {"adapter"=>"mysql2",
   "database"=>"connect_demo",
   "encoding"=>"utf8",
   "port"=>3306,
   "username"=>"connect_demo",
   "password"=>nil,
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "host"=>"connect-staging.c90ubbnnizhv.us-west-2.rds.amazonaws.com"},
 "integration"=>
  {"adapter"=>"mysql2",
   "database"=>"connect",
   "encoding"=>"utf8",
   "port"=>3306,
   "username"=>"connect_int",
   "password"=>nil,
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "host"=>"connect-integration.c90ubbnnizhv.us-west-2.rds.amazonaws.com"},
 "preproduction"=>
  {"adapter"=>"mysql2",
   "database"=>"connect",
   "encoding"=>"utf8",
   "port"=>3306,
   "username"=>"connect_preprod",
   "password"=>nil,
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "host"=>"connect-preprod.c90ubbnnizhv.us-west-2.rds.amazonaws.com"},
 "production"=>
  {"adapter"=>"mysql2",
   "database"=>"connect",
   "encoding"=>"utf8",
   "port"=>3306,
   "username"=>"connect_prod",
   "password"=>nil,
   "sslca"=>"/var/www/connect/deploy-scripts/certs/rds-ca-2015-us-west-2.pem",
   "host"=>"connect.c90ubbnnizhv.us-west-2.rds.amazonaws.com"}}
   
# Perform deep diff showing differences between a and b if there are any
def deep_diff(a, b)
 (a.keys | b.keys).each_with_object({}) do |k, diff|
   if a[k] != b[k]
     if a[k].is_a?(Hash) && b[k].is_a?(Hash)
       diff[k] = deep_diff(a[k], b[k])
     else
       diff[k] = [a[k], b[k]]
     end
   end
   diff
 end
end

# pp deep_diff(new_config, original) ->
# The final is that we have a port and ENV['DB_PASSWORD'] supplied to :local and :test environments 
{
  "local"=>{"port"=>[3306, nil], "password"=>[nil, "development"]},
   "test"=>{"port"=>[3306, nil], "password"=>[nil, "development"]}
}

Can you also test with not-nil ENV values for DB_DATABASE, DB_USERNAME and DB_PASSWORD?