normalize-participant-names.rb

require('mongo')

def client
    @client ||= Mongo::Client.new([ '127.0.0.1:27017' ], :database => 'network-dev')
end

def participants
    client[:participants]
end

participants.find().each do |participant|
	puts participant
	numerals = ['i', 'ii', 'iii', 'iv', 'v', 'vi', 'vii', 'viii']
    if participant[:firstName] and participant[:lastName]
		names = [ participant[:firstName], participant[:lastName] ]
		names.map! do |name|
			# Handle hyphenated names
			if name.include? '-'
				name.split('-').map(&:capitalize).join('-')
				
			# Handle split up names
			elsif name.include? ' '
				name_parts = name.split(' ').map(&:capitalize)
				
				# Handle numerals
				name_parts.map! do |name_part|
					if numerals.include? name_part.downcase
						name_part.upcase
					else
						name_part
					end
				end
				name_parts.join(' ')
			else
	        		name.capitalize
			end
		end

        participants.update_one({ :_id => participant[:_id] }, { "$set" => {:firstName => names[0], :lastName => names[1], :displayName => names[0] + " " + names[1] } })
    end
end

This worked for all my test cases