leaderboard¶ ↑

Leaderboards backed by Redis in Ruby, redis.io.

Builds off ideas proposed in blog.agoragames.com/2011/01/01/creating-high-score-tables-leaderboards-using-redis/.

Install the gem:

gem install multi-leaderboard Make sure your redis server is running! Redis configuration is outside the scope of this README, but check out the Redis documentation, redis.io/documentation.

I modified the leaderboard gem from agoragames so that instead of making a different Redis connection for each leaderboard object, it would share one Redis connection between all of the leaderboard objects. This is not a perfect system for everyone, but for my use case, I had a ton of leaderboard objects, and my app would crash after so many connections were made. This circumvents that problem for me. I hope you find it useful.

The gem has been built and tested under Ruby 1.8.7 and Ruby 1.9.2

Create a new leaderboard or attach to an existing leaderboard named ‘highscores’:

ruby-1.8.7-p302 > highscore_lb = Leaderboard.new('highscores')
 => #<Leaderboard:0x1018e4250 @page_size=25, @port=6379, @host="localhost", @redis_connection=#<Redis client v2.1.1 connected to redis://localhost:6379/0 (Redis v2.1.10)>, @leaderboard_name="highscores">

If you need to pass in options for Redis, you can do this with the redis_options parameter:

redis_options = {:host => 'localhost', :port => 6379, :password => 'password', :db => 'some_redis_db'}
highscore_lb = Leaderboard.new('highscores', redis_options[:host], redis_options[:port], Leaderboard::DEFAULT_PAGE_SIZE, redis_options))

You can set the page size to something other than the default page size (25):

ruby-1.8.7-p302 > highscore_lb.page_size = 5
 => 5 
ruby-1.8.7-p302 > highscore_lb
 => #<Leaderboard:0x1018e2130 @leaderboard_name="highscores", @page_size=5, @port=6379, @redis_connection=#<Redis client v2.1.1 connected to redis://localhost:6379/0 (Redis v2.1.10)>, @host="localhost", @redis_options={:host=>"localhost", :port=>6379}>

Add members to your leaderboard:

ruby-1.8.7-p302 > 1.upto(10) do |index|
ruby-1.8.7-p302 >     highscore_lb.add_member("member_#{index}", index)
ruby-1.8.7-p302 ?>  end
 => 1

Get some information about your leaderboard:

ruby-1.8.7-p302 > highscore_lb.total_members
 => 10 
ruby-1.8.7-p302 > highscore_lb.total_pages
 => 1

Get some information about a specific member(s) in the leaderboard:

ruby-1.8.7-p302 > highscore_lb.score_for('member_4')
 => 4.0 
ruby-1.8.7-p302 > highscore_lb.rank_for('member_4')
 => 7 
ruby-1.8.7-p302 > highscore_lb.rank_for('member_10')
 => 1

Get page 1 in the leaderboard:

ruby-1.8.7-p302 > highscore_lb.leaders(1)

=> [{:member=>“member_10”, :rank=>1, :score=>“10”}, {:member=>“member_9”, :rank=>2, :score=>“9”}, {:member=>“member_8”, :rank=>3, :score=>“8”}, {:member=>“member_7”, :rank=>4, :score=>“7”}, {:member=>“member_6”, :rank=>5, :score=>“6”}, {:member=>“member_5”, :rank=>6, :score=>“5”}, {:member=>“member_4”, :rank=>7, :score=>“4”}, {:member=>“member_3”, :rank=>8, :score=>“3”}, {:member=>“member_2”, :rank=>9, :score=>“2”}, {:member=>“member_1”, :rank=>10, :score=>“1”}] Add more members to your leaderboard:

ruby-1.8.7-p302 > 50.upto(95) do |index|
ruby-1.8.7-p302 >     highscore_lb.add_member("member_#{index}", index)
ruby-1.8.7-p302 ?>  end
 => 50 
ruby-1.8.7-p302 > highscore_lb.total_pages
 => 3

Get an “Around Me” leaderboard for a member:

ruby-1.8.7-p302 > highscore_lb.around_me('member_53')

=> [{:member=>“member_65”, :rank=>31, :score=>“65”}, {:member=>“member_64”, :rank=>32, :score=>“64”}, {:member=>“member_63”, :rank=>33, :score=>“63”}, {:member=>“member_62”, :rank=>34, :score=>“62”}, {:member=>“member_61”, :rank=>35, :score=>“61”}, {:member=>“member_60”, :rank=>36, :score=>“60”}, {:member=>“member_59”, :rank=>37, :score=>“59”}, {:member=>“member_58”, :rank=>38, :score=>“58”}, {:member=>“member_57”, :rank=>39, :score=>“57”}, {:member=>“member_56”, :rank=>40, :score=>“56”}, {:member=>“member_55”, :rank=>41, :score=>“55”}, {:member=>“member_54”, :rank=>42, :score=>“54”}, {:member=>“member_53”, :rank=>43, :score=>“53”}, {:member=>“member_52”, :rank=>44, :score=>“52”}, {:member=>“member_51”, :rank=>45, :score=>“51”}, {:member=>“member_50”, :rank=>46, :score=>“50”}, {:member=>“member_10”, :rank=>47, :score=>“10”}, {:member=>“member_9”, :rank=>48, :score=>“9”}, {:member=>“member_8”, :rank=>49, :score=>“8”}, {:member=>“member_7”, :rank=>50, :score=>“7”}, {:member=>“member_6”, :rank=>51, :score=>“6”}, {:member=>“member_5”, :rank=>52, :score=>“5”}, {:member=>“member_4”, :rank=>53, :score=>“4”}, {:member=>“member_3”, :rank=>54, :score=>“3”}, {:member=>“member_2”, :rank=>55, :score=>“2”}] Get rank and score for an arbitrary list of members (e.g. friends):

ruby-1.8.7-p302 > highscore_lb.ranked_in_list(['member_1', 'member_62', 'member_67'], true)
 => [{:rank=>55, :member=>"member_1", :score=>1.0}, {:rank=>33, :member=>"member_62", :score=>62.0}, {:rank=>28, :member=>"member_67", :score=>67.0}]

remove_member(member): Remove a member from the leaderboard total_members_in_score_range(min_score, max_score): Count the number of members within a score range in the leaderboard change_score_for(member, delta): Change the score for a member by some amount delta (delta could be positive or negative) check_member?(member): Check to see whether member is in the leaderboard score_and_rank_for(member, use_zero_index_for_rank = false): Retrieve the score and rank for a member in a single call remove_members_in_score_range(min_score, max_score): Remove members from the leaderboard within a score range merge_leaderboards(destination, keys, options = {:aggregate => :min}): Merge leaderboards given by keys with this leaderboard into destination intersect_leaderboards(destination, keys, options = {:aggregate => :min}): Intersect leaderboards given by keys with this leaderboard into destination

10 million sequential scores insert:

ruby-1.8.7-p302 > insert_time = Benchmark.measure do
ruby-1.8.7-p302 >       1.upto(10000000) do |index|
ruby-1.8.7-p302 >           highscore_lb.add_member("member_#{index}", index)
ruby-1.8.7-p302 ?>      end
ruby-1.8.7-p302 ?>  end
 => #<Benchmark::Tms:0x101605660 @label="", @stime=173.61, @total=577.52, @real=911.718175172806, @utime=403.91, @cstime=0.0, @cutime=0.0>

Average time to request an arbitrary page from the leaderboard:

ruby-1.8.7-p302 > requests_to_make = 50000
 => 50000 
ruby-1.8.7-p302 > lb_request_time = 0
 => 0 
ruby-1.8.7-p302 > 1.upto(requests_to_make) do
ruby-1.8.7-p302 >       lb_request_time += Benchmark.measure do
ruby-1.8.7-p302 >           highscore_lb.leaders(rand(highscore_lb.total_pages))
ruby-1.8.7-p302 ?>      end.total
ruby-1.8.7-p302 ?>  end
 => 1 
ruby-1.8.7-p302 > 
ruby-1.8.7-p302 >   p lb_request_time / requests_to_make
0.001808
 => nil

10 million random scores insert:

ruby-1.8.7-p302 > insert_time = Benchmark.measure do
ruby-1.8.7-p302 >       1.upto(10000000) do |index|
ruby-1.8.7-p302 >           highscore_lb.add_member("member_#{index}", rand(50000000))
ruby-1.8.7-p302 ?>      end
ruby-1.8.7-p302 ?>  end
 => #<Benchmark::Tms:0x10164ebf8 @label="", @stime=172.94, @total=577.91, @real=1356.57155895233, @utime=404.97, @cstime=0.0, @cutime=0.0>

Average time to request an arbitrary page from the leaderboard:

ruby-1.8.7-p302 > requests_to_make = 50000
 => 50000 
ruby-1.8.7-p302 > lb_request_time = 0
 => 0 
ruby-1.8.7-p302 > 1.upto(requests_to_make) do
ruby-1.8.7-p302 >       lb_request_time += Benchmark.measure do
ruby-1.8.7-p302 >           highscore_lb.leaders(rand(highscore_lb.total_pages))
ruby-1.8.7-p302 ?>      end.total
ruby-1.8.7-p302 ?>  end
 => 1 
ruby-1.8.7-p302 > 
ruby-1.8.7-p302 >   p lb_request_time / requests_to_make
0.00179680000000001
 => nil

• Bulk insert

• Atomicity for various operations?

• Is nil? OK to return if Redis returns no data or should it be []?

• Check out the latest master to make sure the feature hasn’t been implemented or the bug hasn’t been fixed yet

• Check out the issue tracker to make sure someone already hasn’t requested it and/or contributed it

• Fork the project

• Start a feature/bugfix branch

• Commit and push until you are happy with your contribution

• Make sure to add tests for it. This is important so I don’t break it in a future version unintentionally.

• Please try not to mess with the Rakefile, version, or history. If you want to have your own version, or is otherwise necessary, that is fine, but please isolate to its own commit so I can cherry-pick around it.

Copyright © 2011 David Czarnecki. See LICENSE.txt for further details.