Ruby-on-rails 在 Rails 中显示主机名和数据库名
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Displaying host and database names in Rails
提问by hectorsq
I want to display the current host and database names in a view.
我想在视图中显示当前的主机名和数据库名。
Where can I get these names?
我在哪里可以得到这些名字？
Are there some predefined environment or global variables?
是否有一些预定义的环境或全局变量？
采纳答案by Robert Gamble
You can create a rails configuration object and obtain the necessary information from it:
您可以创建一个 rails 配置对象并从中获取必要的信息：
config = Rails::Configuration.new
host = config.database_configuration[RAILS_ENV]["host"]
database = config.database_configuration[RAILS_ENV]["database"]
See the documentationfor Rails::Configuration for details.
有关详细信息，请参阅Rails::Configuration的文档。
回答by Fernando Almeida
With Rails 3 you can use
使用 Rails 3，您可以使用
Rails.configuration.database_configuration[Rails.env]
or
或者
Rails.application.config.database_configuration[Rails.env]
or
或者
ActiveRecord::Base.connection_config
回答by craic.com
The Rails::configuration.new answer does not work in Rails 3
Rails::configuration.new 答案在 Rails 3 中不起作用
config = Rails::Configuration.new
NoMethodError: undefined method `new' for Rails::Configuration:Module
[...]
If you are using MySQL or Postgres then this works
如果您使用的是 MySQL 或 Postgres，那么这有效
ActiveRecord::Base.connection.current_database
But this only works with drivers that have implemented that method. For example, it will not work for SQLite.
但这仅适用于已实现该方法的驱动程序。例如，它不适用于 SQLite。
回答by Ryan Long
On Rails 3, this is most easily accessed via Rails::Application.config, like so:
在 Rails 3 上，这最容易通过 访问Rails::Application.config，如下所示：
YourApplicationClassName::Application.config.database_configuration[::Rails.env]
If you try to call it directly on Railsinstead of YourApplicationClassName, rails will give you a deperecation warning. If you don't know what your application constant is, try Rails.application.class.namein a Rails console for your app.
如果你尝试直接调用它Rails而不是YourApplicationClassName，rails 会给你一个 deperecation 警告。如果您不知道您的应用程序常量是什么，请Rails.application.class.name在您的应用程序的 Rails 控制台中尝试。
回答by joshmckin
The method below is nice when you are connected to multiple databases. Tested on Sqlite3 and Mysql2
当您连接到多个数据库时，下面的方法很好。在 Sqlite3 和 Mysql2 上测试
MyModel.connection.instance_variable_get(:@config)[:database]
回答by mikowiec
Tested in Rails console:
在 Rails 控制台中测试：
ActiveRecord::Base.connection.instance_variable_get(:@config)
next info should be out: adapter, host, encoding, reconnect, database name, username, pass
下一个信息应该是：适配器、主机、编码、重新连接、数据库名称、用户名、通过
回答by toomaj
Just this should work
ActiveRecord::Base.connection.database_name
这应该工作
ActiveRecord::Base.connection.database_name
