Method: ActionBlocks::FilterAdapter#evaluate

Defined in:
lib/action_blocks/data_engine/filter_adapter.rb

#evaluate(expression) ⇒ Object 



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# File 'lib/action_blocks/data_engine/filter_adapter.rb', line 41

def evaluate(expression)
  # Convert Symbol to Arel Attribute
  return @arel_attributes[expression] if expression.class == Symbol

  # Convert Proc to it's result
  if expression.class == Proc
    proc_args = {}
    # debug expression.parameters
    if expression.parameters.include?([:keyreq, :user])
      proc_args[:user] = @user
    end
    return expression.call(**proc_args)
  end

  # Convert expression to Arel Predicate
  if expression.class == Array
    fn, *args = expression
    case fn
    when :user
      return @user.send(args[0])
    when :eq
      left, right = args
      return evaluate(left).eq(evaluate(right))
    when :not_eq
      left, right = args
      return evaluate(left).not_eq(evaluate(right))
    when :and
      return args.map {|x| evaluate(x)}.reduce(&:and)
    when :or
      return args.map {|x| evaluate(x)}.reduce(&:or)
    else
      raise "RLS function #{fn.inspect} not recognized"
    end
  end

  return expression
end