Method: Mongo::Collection::View::Readable#read_preference

Defined in:
lib/mongo/collection/view/readable.rb

#read_preference ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Since:

  • 2.0.0



683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
 
# File 'lib/mongo/collection/view/readable.rb', line 683

def read_preference
  @read_preference ||= begin
    # Operation read preference is always respected, and has the
    # highest priority. If we are in a transaction, we look at
    # transaction read preference and default to client, ignoring
    # collection read preference. If we are not in transaction we
    # look at collection read preference which defaults to client.
    rp = if options[:read]
      options[:read]
    elsif options[:session] && options[:session].in_transaction?
      options[:session].txn_read_preference || collection.client.read_preference
    else
      collection.read_preference
    end
    Lint.validate_underscore_read_preference(rp)
    rp
  end
end