Returns true
if Active Record is connected.
# File activerecord/lib/active_record/connection_handling.rb, line 120 def connected? connection_handler.connected?(connection_specification_name) end
Returns the connection currently associated with the class. This can also be used to “borrow” the connection to do database work unrelated to any of the specific Active Records.
# File activerecord/lib/active_record/connection_handling.rb, line 87 def connection retrieve_connection end
Returns the configuration of the associated connection as a hash:
ActiveRecord::Base.connection_config # => {pool: 5, timeout: 5000, database: "db/development.sqlite3", adapter: "sqlite3"}
Please use only for reading.
# File activerecord/lib/active_record/connection_handling.rb, line 107 def connection_config connection_pool.spec.config end
# File activerecord/lib/active_record/connection_handling.rb, line 111 def connection_pool connection_handler.retrieve_connection_pool(connection_specification_name) || raise(ConnectionNotEstablished) end
Return the specification name from the current class or its parent.
# File activerecord/lib/active_record/connection_handling.rb, line 94 def connection_specification_name if !defined?(@connection_specification_name) || @connection_specification_name.nil? return self == Base ? "primary" : superclass.connection_specification_name end @connection_specification_name end
Establishes the connection to the database. Accepts a hash as input where the :adapter
key must be specified with the name of a database adapter (in lower-case) example for regular databases (MySQL, PostgreSQL, etc):
ActiveRecord::Base.establish_connection( adapter: "mysql2", host: "localhost", username: "myuser", password: "mypass", database: "somedatabase" )
Example for SQLite database:
ActiveRecord::Base.establish_connection( adapter: "sqlite3", database: "path/to/dbfile" )
Also accepts keys as strings (for parsing from YAML for example):
ActiveRecord::Base.establish_connection( "adapter" => "sqlite3", "database" => "path/to/dbfile" )
Or a URL:
ActiveRecord::Base.establish_connection( "postgres://myuser:mypass@localhost/somedatabase" )
In case ActiveRecord::Base.configurations is set (Rails automatically loads the contents of config/database.yml into it), a symbol can also be given as argument, representing a key in the configuration hash:
ActiveRecord::Base.establish_connection(:production)
The exceptions AdapterNotSpecified, AdapterNotFound and ArgumentError
may be returned on an error.
# File activerecord/lib/active_record/connection_handling.rb, line 47 def establish_connection(config = nil) raise "Anonymous class is not allowed." unless name config ||= DEFAULT_ENV.call.to_sym spec_name = self == Base ? "primary" : name self.connection_specification_name = spec_name resolver = ConnectionAdapters::ConnectionSpecification::Resolver.new(Base.configurations) spec = resolver.resolve(config).symbolize_keys spec[:name] = spec_name connection_handler.establish_connection(spec) end
# File activerecord/lib/active_record/connection_handling.rb, line 124 def remove_connection(name = nil) name ||= @connection_specification_name if defined?(@connection_specification_name) # if removing a connection that has a pool, we reset the # connection_specification_name so it will use the parent # pool. if connection_handler.retrieve_connection_pool(name) self.connection_specification_name = nil end connection_handler.remove_connection(name) end
# File activerecord/lib/active_record/connection_handling.rb, line 115 def retrieve_connection connection_handler.retrieve_connection(connection_specification_name) end
© 2004–2017 David Heinemeier Hansson
Licensed under the MIT License.