module ActiveRecord
class Base
class ConnectionSpecification #:nodoc:
attr_reader :config, :adapter_method
def initialize (config, adapter_method)
@config, @adapter_method = config, adapter_method
end
##
# Builds a ConnectionSpecification from user input
class Resolver # :nodoc:
attr_reader :config, :klass, :configurations
def initialize(config, configurations)
@config = config
@configurations = configurations
end
def spec
case config
when nil
raise AdapterNotSpecified unless defined?(Rails.env)
resolve_string_connection Rails.env
when Symbol, String
resolve_string_connection config.to_s
when Hash
resolve_hash_connection config
end
end
private
def resolve_string_connection(spec) # :nodoc:
hash = configurations.fetch(spec) do |k|
connection_url_to_hash(k)
end
raise(AdapterNotSpecified, "#{spec} database is not configured") unless hash
resolve_hash_connection hash
end
def resolve_hash_connection(spec) # :nodoc:
spec = spec.symbolize_keys
raise(AdapterNotSpecified, "database configuration does not specify adapter") unless spec.key?(:adapter)
begin
require "active_record/connection_adapters/#{spec[:adapter]}_adapter"
rescue LoadError => e
raise LoadError, "Please install the #{spec[:adapter]} adapter: `gem install activerecord-#{spec[:adapter]}-adapter` (#{e.message})", e.backtrace
end
adapter_method = "#{spec[:adapter]}_connection"
ConnectionSpecification.new(spec, adapter_method)
end
def connection_url_to_hash(url) # :nodoc:
config = URI.parse url
adapter = config.scheme
adapter = "postgresql" if adapter == "postgres"
spec = { :adapter => adapter,
:username => config.user,
:password => config.password,
:port => config.port,
:database => config.path.sub(%r{^/},""),
:host => config.host }
spec.reject!{ |_,value| !value }
if config.query
options = Hash[config.query.split("&").map{ |pair| pair.split("=") }].symbolize_keys
spec.merge!(options)
end
spec
end
end
end
##
# :singleton-method:
# The connection handler
class_attribute :connection_handler, :instance_writer => false
self.connection_handler = ConnectionAdapters::ConnectionHandler.new
# Returns the connection currently associated with the class. This can
# also be used to "borrow" the connection to do database work that isn't
# easily done without going straight to SQL.
def connection
self.class.connection
end
# Establishes the connection to the database. Accepts a hash as input where
# the <tt>:adapter</tt> 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 => "sqlite",
# :database => "path/to/dbfile"
# )
#
# Also accepts keys as strings (for parsing from YAML for example):
#
# ActiveRecord::Base.establish_connection(
# "adapter" => "sqlite",
# "database" => "path/to/dbfile"
# )
#
# Or a URL:
#
# ActiveRecord::Base.establish_connection(
# "postgres://myuser:mypass@localhost/somedatabase"
# )
#
# The exceptions AdapterNotSpecified, AdapterNotFound and ArgumentError
# may be returned on an error.
def self.establish_connection(spec = ENV["DATABASE_URL"])
resolver = ConnectionSpecification::Resolver.new spec, configurations
spec = resolver.spec
unless respond_to?(spec.adapter_method)
raise AdapterNotFound, "database configuration specifies nonexistent #{spec[:adapter]} adapter"
end
remove_connection
connection_handler.establish_connection name, spec
end
class << self
# 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.
def connection
retrieve_connection
end
def connection_id
Thread.current['ActiveRecord::Base.connection_id']
end
def connection_id=(connection_id)
Thread.current['ActiveRecord::Base.connection_id'] = connection_id
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.
def connection_config
connection_pool.spec.config
end
def connection_pool
connection_handler.retrieve_connection_pool(self) or raise ConnectionNotEstablished
end
def retrieve_connection
connection_handler.retrieve_connection(self)
end
# Returns true if Active Record is connected.
def connected?
connection_handler.connected?(self)
end
def remove_connection(klass = self)
connection_handler.remove_connection(klass)
end
def clear_active_connections!
connection_handler.clear_active_connections!
end
delegate :clear_reloadable_connections!,
:clear_all_connections!,:verify_active_connections!, :to => :connection_handler
end
end
end