type declaration

assignment2/paxos.py

 # http://pymotw.com/2/SocketServer/
+from typing import Tuple, Dict, Set
 from functools import total_ordering
 import socketserver
 import pickle
 
+
 # Paxos servers
 class Paxos(socketserver.TCPServer):
     def __init__(self, address, servers) -> None:
         # address is a tuple of (ip, port)
-        self.address = address                                      # Our address (ip, port)
-        self.servers = servers                                      # All servers addresses
+        self.address: Tuple[str, int] = address                               # Our address tuple (ip, port)
+        self.servers = servers                                                # All servers addresses TODO: is this a tuple or list of server addresses?
 
         # Sets up other variables
-        self.is_leader = False                                      # Are we the leader?
-        self.ballot = BallotNumber(1, self.address)                 # Our ballot number
-        self.highestBallotSeen = BallotNumber(0, self.address)      # Highest ballot number seen
-        self.proposals = dict()                                     # Used by leader to send P2A to acceptors
-        self.accepted = dict()                                      # Used by acceptors in P2A and also P1B
-        self.log = dict()                                           # The log
-        self.leader_recent_ping = False                             # True if we think leader is alive
+        self.is_leader: bool = False                                          # Are we the leader?
+        self.ballot: BallotNumber = BallotNumber(1, self.address)             # Our ballot number
+        self.highestBallotSeen: BallotNumber = BallotNumber(0, self.address)  # Highest ballot number seen
+        self.proposals: Dict[int, Proposal] = dict()                          # Used by leader to send P2A to acceptors, slot number -> proposal
+        self.accepted: Dict[int, Proposal] = dict()                           # Used by acceptors in P2A and also P1B, slot number -> proposal
+        self.log: Dict[int, Proposal] = dict()                                # The log
+        self.leader_recent_ping: bool = False                                 # True if we think leader is alive
 
         # for proposal phase
-        self.slot_in = 1                                            # First non-executed proposal slot (+1 last executed slot)
-        self.slot_out = 1                                           # First empty slot (+1 last proposed slot)
-        self.slot_to_acceptors = dict()                             # Used by leader to decide majority for each slot after P2B
+        self.slot_in: int = 1                                                 # First non-executed proposal slot (+1 last executed slot)
+        self.slot_out: int = 1                                                # First empty slot (+1 last proposed slot)
+        self.slot_to_acceptors: Dict[int, Set[Tuple[str, int]]] = dict()      # Used by leader to decide majority for each slot after P2B, Multimap<Integer, Address>
 
         # for leader election
-        self.voters = set()                                         # Yes votes for leader election
-        self.p1b_replies = dict()                                   # Accepted values for each slot by acceptors that voted yes
+        self.voters: Set[Tuple[str, int]] = set()                             # Yes votes for leader election
+        self.p1b_replies: Dict[int, Proposal] = dict()                        # Accepted values for each slot by acceptors that voted yes, slot number -> proposal
         # ...
 
         # Default leader during setup
         if self.address == servers[0]:
             self.is_leader = True
-        
+
         socketserver.TCPServer.__init__(self, address, PaxosClientRequestHandler)
 
 
@@ -57,12 +59,12 @@ class PaxosClientRequestHandler(socketserver.BaseRequestHandler):
         data = self.request.recv(1024).strip() # DEBUG LOG
         print("{} wrote:".format(self.client_address[0])) # DEBUG LOG
         print(data) # DEBUG LOG
-        
+
         # test deserialize
         paxos_req = pickle.loads(data)
         print(paxos_req, "\n")
         # TODO: Change data into a format known for lock or unlock
-        
+
 
         # Propose
         prop = Proposal(BallotNumber(self.ballot().seq_num, self.address()), data)
@@ -75,7 +77,7 @@ class PaxosClientRequestHandler(socketserver.BaseRequestHandler):
         # Wait untl hear majority
 
         # Send back result
-        self.request.sendall(data.upper()) # TESTING CODE 
+        self.request.sendall(data.upper()) # TESTING CODE
 
 
 @total_ordering
@@ -83,12 +85,12 @@ class Proposal:
     def __init__(self, ballot, value) -> None:
         self.ballot = ballot
         self.value = value
-    
+
     def __lt__(self, other) -> bool:
         if not self._is_valid_operand(other):
             return NotImplemented
         return self.ballot < other.ballot
-        
+
     def __eq__(self, other) -> bool:
         if not self._is_valid_operand(other):
             return NotImplemented
@@ -118,12 +120,12 @@ class BallotNumber:
         else:
             # Same seq_num, use address for break
             return self.addr[1] < other.addr[1]
-        
+
     def __eq__(self, other) -> bool:
         if not self._is_valid_operand(other):
             return NotImplemented
         return ((self.seq_num, self.addr) == (other.seq_num, other.addr))
-        
+
 @total_ordering
 class BallotValuePair:
     def __init__(self, ballot_num, value) -> None:
@@ -138,9 +140,9 @@ class BallotValuePair:
     def __lt__(self, other) -> bool:
         if not self._is_valid_operand(other):
             return NotImplemented
-        
+
         return self.ballot_num < other.ballot_num
-        
+
     def __eq__(self, other) -> bool:
         if not self._is_valid_operand(other):
             return NotImplemented