Add files for Paxos decision system.

DecisionSystem/PaxosDecision/acceptor.py

@@ -0,0 +1,26 @@
+from proposer import Proposer
+from paxosmessenger import Messenger
+
+class Acceptor():
+    highest_proposal = None
+    highest_promise = None
+    messenger = None
+
+    def __init__(self, messenger: Messenger):
+        self.messenger = messenger
+
+    def on_message(self, client, userdata, message):
+        pass
+
+    def prepare(self):
+        pass
+
+    def accept_request(self, fromt_uid, proposal_id, value):
+        '''
+        Called when an accept message is received from a proposer
+        '''
+        if proposal_id >= self.highest_promise:
+            self.highest_promise     = proposal_id
+            self.accepted_id     = proposal_id
+            self.accepted_value  = value
+            self.messenger.send_accepted(proposal_id, self.accepted_value)