module ActiveRecord::ConnectionHandling

Constants

DEFAULT_ENV
RAILS_ENV

Public Instance Methods

Returns true if Active Record is connected.

# File activerecord/lib/active_record/connection_handling.rb, line 117
def connected?
  connection_handler.connected?(self)
end

connection() Show source

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 86
def connection
  retrieve_connection
end

connection_config() Show source

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 104
def connection_config
  connection_pool.spec.config
end

connection_id() Show source

# File activerecord/lib/active_record/connection_handling.rb, line 90
def connection_id
  ActiveRecord::RuntimeRegistry.connection_id
end

connection_id=(connection_id) Show source

# File activerecord/lib/active_record/connection_handling.rb, line 94
def connection_id=(connection_id)
  ActiveRecord::RuntimeRegistry.connection_id = connection_id
end

connection_pool() Show source

# File activerecord/lib/active_record/connection_handling.rb, line 108
def connection_pool
  connection_handler.retrieve_connection_pool(self) or raise ConnectionNotEstablished
end

establish_connection(spec = nil) Show source

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:  "mysql",
  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(spec = nil)
  spec     ||= DEFAULT_ENV.call.to_sym
  resolver =   ConnectionAdapters::ConnectionSpecification::Resolver.new configurations
  spec     =   resolver.spec(spec)

  unless respond_to?(spec.adapter_method)
    raise AdapterNotFound, "database configuration specifies nonexistent #{spec.config[:adapter]} adapter"
  end

  remove_connection
  connection_handler.establish_connection self, spec
end

remove_connection(klass = self) Show source

# File activerecord/lib/active_record/connection_handling.rb, line 121
def remove_connection(klass = self)
  connection_handler.remove_connection(klass)
end

retrieve_connection() Show source

# File activerecord/lib/active_record/connection_handling.rb, line 112
def retrieve_connection
  connection_handler.retrieve_connection(self)
end