Add Kademlia constants.

dht/constants.py

@@ -0,0 +1,46 @@
+# ######## KADEMLIA CONSTANTS ###########
+
+BIT_NODE_ID_LEN = 160
+HEX_NODE_ID_LEN = BIT_NODE_ID_LEN // 4
+
+# Small number representing the degree of
+# parallelism in network calls
+ALPHA = 3
+
+# Maximum number of contacts stored in a bucket
+# NOTE: Should be an even number.
+K = 24  # pylint: disable=invalid-name
+
+# Maximum number of contacts stored in the
+# replacement cache of a bucket
+# NOTE: Should be an even number.
+CACHE_K = 32
+
+# Timeout for network operations
+# [seconds]
+RPC_TIMEOUT = 0.1
+
+# Delay between iterations of iterative node lookups
+# (for loose parallelism)
+# [seconds]
+ITERATIVE_LOOKUP_DELAY = RPC_TIMEOUT / 2
+
+# If a KBucket has not been used for this amount of time, refresh it.
+# [seconds]
+REFRESH_TIMEOUT = 60 * 60 * 1000  # 1 hour
+
+# The interval in which the node should check whether any buckets
+# need refreshing or whether any data needs to be republished
+# [seconds]
+CHECK_REFRESH_INTERVAL = REFRESH_TIMEOUT / 5
+
+# The interval at which nodes replicate (republish/refresh)
+# the data they hold
+# [seconds]
+REPLICATE_INTERVAL = REFRESH_TIMEOUT
+
+# The time it takes for data to expire in the network;
+# the original publisher of the data  will also republish
+# the data at this time if it is still valid
+# [seconds]
+DATE_EXPIRE_TIMEOUT = 86400  # 24 hours

tests/dht/test_contact.py

@@ -1,6 +1,6 @@
 import unittest
 
-from dht import contact
+from dht import constants, contact
 
 
 class TestContact(unittest.TestCase):
@@ -9,8 +9,8 @@ class TestContact(unittest.TestCase):
     """
     @classmethod
     def setUpClass(cls):
-        cls.guid1 = '1' * 40
-        cls.guid2 = 'f' * 40
+        cls.guid1 = '1' * constants.HEX_NODE_ID_LEN
+        cls.guid2 = 'f' * constants.HEX_NODE_ID_LEN
         cls.ipv4 = '123.45.67.89'
         cls.ipv6 = '2001:db8:85a3::8a2e:370:7334'
         cls.port1 = 12345