gevent-dht

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This is a basic implementation of a dht using gevent.

There are two things you have to concern yourself with. 1.) Bootstrapping the network. The following example creates a network of one node

import gevent_dht table = gevent_dht.distributedHashTable(None) #This tell the network it # is the first node by default it listens on port 8339 #

table['key_1'] = [1,2,3] #This sets a value in our hash table for i in table['key_1']: print i #Prints 123

table.append('key_1', 4) #Adds an item to a list in a hash table #Note if the key is not in the hash table #It will put a list in place and then append #to it.

#Now we are adding another node

other_clients_table = gevent_dht.distributedHashTable( '127.0.0.1:8339', local_port = 8449) #Another client has connected. It supplied the address of # a node in the network to connect with the preexisting network

for i in other_clients_table['key_1']: print i #Prints 1234

So in order to connect to an existing network you must have a way to get an address of another member. It doesn't have to be the first node but needs to be a node in the network.

2.) Latency/ This may fail.

Keys are not guarenteed to persist forever, nodes may crash, the network may eat messages etc... While we are working in tcp/ip mode there may still be bizarre glitches. Always check for a return value of None.

Additionally due to the time it takes for messages to travel the network sometimes a key will not be immedietly available after you set it or when you get the result back it may not be completely current.