def initialize(aws_access_key_id=nil, aws_secret_access_key=nil, params={})
init({ :name => 'RDS',
:default_host => ENV['RDS_URL'] ? URI.parse(ENV['RDS_URL']).host : DEFAULT_HOST,
:default_port => ENV['RDS_URL'] ? URI.parse(ENV['RDS_URL']).port : DEFAULT_PORT,
:default_service => ENV['RDS_URL'] ? URI.parse(ENV['RDS_URL']).path : DEFAULT_PATH,
:default_protocol => ENV['RDS_URL'] ? URI.parse(ENV['RDS_URL']).scheme : DEFAULT_PROTOCOL,
:default_api_version => ENV['RDS_API_VERSION'] || API_VERSION },
aws_access_key_id || ENV['AWS_ACCESS_KEY_ID'],
aws_secret_access_key || ENV['AWS_SECRET_ACCESS_KEY'],
params)
end