development: &default
  adapter: mysql2
  username: <%= ENV.fetch('MYSQL_USER',     'foo') %>
  password: <%= ENV.fetch('MYSQL_PASSWORD', 'bar') %>
  host:     <%= ENV.fetch('MYSQL_HOST',     '127.0.0.1') %>
  database: app_development
  encoding: utf8
  redis_db: 0
  reconnect: true

test: &test
  <<: *default
  database: app_test
.....