consistent-hash

Implements consistent hashing that can be used when the number of server nodes can increase or decrease.The algorithm that is used for consistent hashing is the same as libketama <https://github.com/RJ/ketama>

Usage

It’s so easy to use^_^:

from consistent_hash import ConsistentHash

# You can construct consistent hash with the below three ways
con_hash = ConsistentHash({'192.168.0.101:11212':1, '192.168.0.102:11212':2, '192.168.0.103:11212':1})
# Or
con_hash = ConsistentHash(['192.168.0.101:11212', '192.168.0.102:11212', '192.168.0.103:11212']))
# Or
con_hash = ConsistentHash('192.168.0.101:11212')

# Add servers to hash ring
con_hash.add_nodes({'192.168.0.104:11212':1})
# Get a server via the key of object
server = con_hash.get_node('my_key')
# Delete the server from hash ring, you don't need to indicate weights
con_hash.del_nodes(['192.168.0.102:11212', '192.168.0.104:11212'])

Unit test

• Firstly, install nose which extends unittest to make testing easier:

  pip install nose

• Then, run tests:

  # Option -s any stdout output will be printed immediately
  # and -v be more verbose
  nosetests -s -v

More information about nose <https://nose.readthedocs.org/en/latest/>