rails4 - Psych::BadAlias：未知别名：test

Question

trying to deploy my project using Capistrano cap deploy:migrate , I get an error in my database.yml on the test alias ( which is just running fine on local server)

development:
   database: db_dev
   adapter: mysql2
   username: xxxxxx
   password: xxxxxx
   host: localhost
   encoding: utf8

test: &test
   database: db_test
   adapter: mysql2
   username: xxxxxx
   password: xxxxxx
   host: localhost
   encoding: utf8

production:
   database: db_prod
   adapter: mysql2
   username: xxxxxxxx
   password: xxxxxxx
   host: localhost
   encoding: utf8

cucumber:
   <<: *test

the console log is :

           rake aborted!
   Psych::BadAlias: Unknown alias: test
   /railties-4.0.3/lib/rails/application/configuration.rb:106:in `database_configuration'
   /activerecord-4.0.3/lib/active_record/railtie.rb:175:in `block (2 levels) in <class:Railtie>'
   /activesupport-4.0.3/lib/active_support/lazy_load_hooks.rb:38:in `instance_eval'
   /activesupport-4.0.3/lib/active_support/lazy_load_hooks.rb:38:in `execute_hook'
   /activesupport-4.0.3/lib/active_support/lazy_load_hooks.rb:28:in `block in on_load'
   /activesupport-4.0.3/lib/active_support/lazy_load_hooks.rb:27:in `each'
   /activesupport-4.0.3/lib/active_support/lazy_load_hooks.rb:27:in `on_load'
   /activerecord-4.0.3/lib/active_record/railtie.rb:174:in `block in <class:Railtie>'
   /railties-4.0.3/lib/rails/initializable.rb:30:in `instance_exec'
   /railties-4.0.3/lib/rails/initializable.rb:30:in `run'
   /railties-4.0.3/lib/rails/initializable.rb:55:in `block in run_initializers'
   /railties-4.0.3/lib/rails/initializable.rb:54:in `run_initializers'
   /railties-4.0.3/lib/rails/application.rb:215:in `initialize!'
   /railties-4.0.3/lib/rails/railtie/configurable.rb:30:in `method_missing'
   /home/kadoudal/rails/swim-tech.eu/site/swimtech/releases/20140326140458/config/environment.rb:6:in `<top (required)>'
   /activesupport-4.0.3/lib/active_support/dependencies.rb:229:in `require'
   /activesupport-4.0.3/lib/active_support/dependencies.rb:229:in `block in require'
   /activesupport-4.0.3/lib/active_support/dependencies.rb:214:in `load_dependency'
   /activesupport-4.0.3/lib/active_support/dependencies.rb:229:in `require'
   /railties-4.0.3/lib/rails/application.rb:189:in `require_environment!'
   /railties-4.0.3/lib/rails/application.rb:250:in `block in run_tasks_blocks'
   Tasks: TOP => db:migrate => environment

Answer 1

I don't believe you can alias test, development, or production as they are assigned based on the environment you boot in (if environment is production, the production settings will be applied). The issue is that if this were to work, cucumber would only be usable in the test environment.

I used something akin to the below:

  base: &base
     adapter: mysql2
     host: address.com
     encoding: utf8
     adapter: mysql2
     username: xxxxxx
     password: xxxxxx

  development:
     database: db_dev
     <<: *base

  test:
     database: db_test
     <<: *base

  production:
     database: db_prod
     <<: *base

  cucumber:
     database: cucumber
     <<: *base

Answer 2

您可以通过将aliases: true参数传递给YAML.safe_load方法来避免此问题：

YAML.safe_load(File.read('config/database.yml'), aliases: true)