DynamoDB example Leaderboard using boto

leaderboard_boto.py

import boto
from boto.dynamodb.exceptions import *
from boto.dynamodb.batch import *
import pprint

class Leaderboard:
  def __init__(self, game_mode):
    self.conn  = boto.connect_dynamodb()
    self.table = self.conn.get_table("leaderboard_" + game_mode)

  def add_score(self, user, score):
    item = self.table.new_item(
        hash_key=user,
        attrs={'score': score}
    )
    item.put()

  def get_board(self, friends):
    scores = self.table.batch_get_item(friends)
    return sorted(scores, reverse=True, key=lambda item: item['score'])

lb = Leaderboard("deathmatch")
lb.add_score('nateware', 923)
lb.add_score('LaZyb0ne', 1492)
lb.add_score('grizzly99', 1612)
lb.add_score('LaZyb0ne', 2819) # new high score
lb.add_score('xMotherx', 1209)

# Retrieve friends in-game somehow
#friends = ['nateware','missing','grizzly99','xMotherx','absent','LaZyb0ne']
friends = current_user.friends_list
scores  = lb.get_board(friends)

# Display leaderboard
print("=== friends leaderboard ===")
for item in scores:
  print("%s: %s" % (item['username'], item['score']))