mucking around

global.json

@@ -1 +1 @@
-{"projects":["src","test"]}
+{ "projects": ["src", "test"] }

src/Rafty/Concensus/AppendEntries.cs

@@ -1,13 +1,14 @@
-using System;
-using System.Collections.Generic;
-using Rafty.Log;
-
 namespace Rafty.Concensus
 {
+    using System;
+    using System.Collections.Generic;
+    using Log;
+
     public sealed class AppendEntries : Message
     {
-        public AppendEntries(long term, Guid leaderId, long previousLogIndex, long previousLogTerm, List<LogEntry> entries, long leaderCommitIndex)
-            :base(Guid.NewGuid())
+        public AppendEntries(long term, Guid leaderId, long previousLogIndex, long previousLogTerm,
+            List<LogEntry> entries, long leaderCommitIndex)
+            : base(Guid.NewGuid())
         {
             Term = term;
             LeaderId = leaderId;
@@ -16,18 +17,18 @@ public AppendEntries(long term, Guid leaderId, long previousLogIndex, long previ
             Entries = entries;
             LeaderCommitIndex = leaderCommitIndex;
         }
-        
+
         // term leader’s term
-        public long Term {get;private set;}
+        public long Term { get; private set; }
         // leaderId so follower can redirect clients
-        public Guid LeaderId {get;private set;}
+        public Guid LeaderId { get; private set; }
         // prevLogIndex index of log entry immediately preceding new ones
-        public long PreviousLogIndex {get;private set;}
+        public long PreviousLogIndex { get; private set; }
         // prevLogTerm term of prevLogIndex entry
-        public long PreviousLogTerm {get;private set;}
+        public long PreviousLogTerm { get; private set; }
         // entries[] log entries to store (empty for heartbeat may send more than one for efficiency)
-        public List<LogEntry> Entries {get;private set;}
+        public List<LogEntry> Entries { get; private set; }
         // leaderCommit leader’s commitIndex
-        public long LeaderCommitIndex {get;private set;}
+        public long LeaderCommitIndex { get; private set; }
     }
 }

src/Rafty/Concensus/AppendEntriesBuilder.cs

@@ -1,17 +1,17 @@
-using System;
-using System.Collections.Generic;
-using Rafty.Log;
-
 namespace Rafty.Concensus
 {
+    using System;
+    using System.Collections.Generic;
+    using Log;
+
     public class AppendEntriesBuilder
     {
-        private long _term;
+        private List<LogEntry> _entries;
+        private long _leaderCommitIndex;
         private Guid _leaderId;
-        private long _previousLogIndex; 
+        private long _previousLogIndex;
         private long _previousLogTerm;
-        private List<LogEntry> _entries; 
-        private long _leaderCommitIndex;
+        private long _term;
 
         public AppendEntriesBuilder WithTerm(long term)
         {
@@ -51,7 +51,7 @@ public AppendEntriesBuilder WithLeaderCommitIndex(long leaderCommitIndex)
 
         public AppendEntriesBuilder WithEntry(LogEntry entry)
         {
-            _entries = new List<LogEntry>{entry};
+            _entries = new List<LogEntry> {entry};
             return this;
         }
 

src/Rafty/Concensus/BeginElection.cs

@@ -1,10 +1,10 @@
-using System;
-
 namespace Rafty.Concensus
 {
+    using System;
+
     public class BeginElection : Message
     {
-        public BeginElection() 
+        public BeginElection()
             : base(Guid.NewGuid())
         {
         }

src/Rafty/Concensus/Candidate.cs

@@ -1,13 +1,11 @@
-using System.Collections.Generic;
-
 namespace Rafty.Concensus
 {
     public sealed class Candidate : IState
     {
+        private readonly ISendToSelf _sendToSelf;
         private int _votesThisElection;
-        private ISendToSelf _sendToSelf;
 
-        public Candidate(CurrentState currentState, ISendToSelf sendToSelf) 
+        public Candidate(CurrentState currentState, ISendToSelf sendToSelf)
         {
             _sendToSelf = sendToSelf;
             // • On conversion to candidate, start election:
@@ -16,11 +14,12 @@ public Candidate(CurrentState currentState, ISendToSelf sendToSelf)
             // • Vote for self
             _votesThisElection++;
             var votedFor = currentState.Id;
-            var nextState = new CurrentState(currentState.Id, currentState.Peers, nextTerm, votedFor, currentState.Timeout);
+            var nextState = new CurrentState(currentState.Id, currentState.Peers, nextTerm, votedFor,
+                currentState.Timeout);
             CurrentState = nextState;
         }
 
-        public CurrentState CurrentState {get;private set;}
+        public CurrentState CurrentState { get; }
 
         public IState Handle(Timeout timeout)
         {
@@ -35,9 +34,21 @@ public IState Handle(BeginElection beginElection)
             // • Send RequestVote RPCs to all other servers
             CurrentState.Peers.ForEach(peer =>
             {
-                peer.Request(new RequestVote());
+                var requestVoteResponse = peer.Request(new RequestVote());
+
+                if (requestVoteResponse.Grant)
+                {
+                    _votesThisElection++;
+                }
             });
-            return this;
+
+            //If votes received from majority of servers: become leader
+            if (_votesThisElection >= (CurrentState.Peers.Count + 1) / 2 + 1)
+            {
+                return new Leader(CurrentState);
+            }
+
+            return new Follower(CurrentState, _sendToSelf);
         }
     }
 }

src/Rafty/Concensus/CurrentState.cs

@@ -1,8 +1,8 @@
-using System;
-using System.Collections.Generic;
-
 namespace Rafty.Concensus
 {
+    using System;
+    using System.Collections.Generic;
+
     public class CurrentState
     {
         public CurrentState(Guid id, List<IPeer> peers, long currentTerm, Guid votedFor, TimeSpan timeout)
@@ -21,6 +21,6 @@ public CurrentState(Guid id, List<IPeer> peers, long currentTerm, Guid votedFor,
         public Uri Address { get; private set; }
         public Guid Id { get; private set; }
         public List<IPeer> Peers { get; private set; }
-        public TimeSpan Timeout {get;private set;}
+        public TimeSpan Timeout { get; private set; }
     }
 }

src/Rafty/Concensus/Follower.cs

@@ -1,6 +1,3 @@
-using System;
-using System.Collections.Generic;
-
 namespace Rafty.Concensus
 {
     public sealed class Follower : IState
@@ -13,7 +10,7 @@ public Follower(CurrentState state, ISendToSelf sendToSelf)
             _sendToSelf = sendToSelf;
         }
 
-        public CurrentState CurrentState {get;private set;}
+        public CurrentState CurrentState { get; }
 
         public IState Handle(Timeout timeout)
         {

src/Rafty/Concensus/IState.cs

@@ -2,8 +2,8 @@ namespace Rafty.Concensus
 {
     public interface IState
     {
+        CurrentState CurrentState { get; }
         IState Handle(Timeout timeout);
         IState Handle(BeginElection beginElection);
-        CurrentState CurrentState {get;}
     }
 }

src/Rafty/Concensus/Leader.cs

@@ -1,16 +1,15 @@
-using System;
-using System.Collections.Generic;
-
 namespace Rafty.Concensus
 {
+    using System;
+
     public sealed class Leader : IState
     {
-        public Leader(CurrentState currentState) 
+        public Leader(CurrentState currentState)
         {
             CurrentState = currentState;
         }
 
-        public CurrentState CurrentState {get;private set;}
+        public CurrentState CurrentState { get; }
 
         public IState Handle(Timeout timeout)
         {

src/Rafty/Concensus/Message.cs

@@ -1,7 +1,7 @@
-using System;
-
 namespace Rafty.Concensus
 {
+    using System;
+
     public abstract class Message
     {
         public Message(Guid messageId)
@@ -16,7 +16,7 @@ public Message(Guid messageId, TimeSpan delay)
             Delay = delay;
         }
 
-        public Guid MessageId {get;private set;}
-        public TimeSpan Delay {get;private set;}
+        public Guid MessageId { get; private set; }
+        public TimeSpan Delay { get; private set; }
     }
 }

src/Rafty/Concensus/Node.cs

@@ -1,15 +1,14 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Threading;
-
 namespace Rafty.Concensus
-{ 
+{
+    using System;
+    using System.Collections.Generic;
+    using System.Linq;
+
     public class Node : IDisposable, INode
     {
         private readonly List<Guid> _appendEntriesIdsReceived;
-        private Guid _appendEntriesAtPreviousHeartbeat;
         private readonly ISendToSelf _sendToSelf;
+        private Guid _appendEntriesAtPreviousHeartbeat;
 
         public Node(CurrentState initialState, ISendToSelf sendToSelf)
         {
@@ -18,20 +17,25 @@ public Node(CurrentState initialState, ISendToSelf sendToSelf)
             State = new Follower(initialState, _sendToSelf);
         }
 
+        public void Dispose()
+        {
+            _sendToSelf.Dispose();
+        }
+
         public IState State { get; private set; }
 
         public void Handle(Message message)
         {
             //todo - could run middleware type functions here?
             //todo - these handlers should be in a dictionary
-            if(message.GetType() == typeof(BeginElection))
+            if (message.GetType() == typeof(BeginElection))
             {
-                Handle((BeginElection)message);
+                Handle((BeginElection) message);
             }
 
-            if(message.GetType() == typeof(Timeout))
+            if (message.GetType() == typeof(Timeout))
             {
-                Handle((Timeout)message);
+                Handle((Timeout) message);
             }
         }
 
@@ -41,21 +45,15 @@ public AppendEntriesResponse Handle(AppendEntries appendEntries)
             return new AppendEntriesResponse();
         }
 
-        public void Dispose()
-        {
-            _sendToSelf.Dispose();
-        }
-
         private void Handle(BeginElection beginElection)
         {
             State = State.Handle(beginElection);
-
             _sendToSelf.Publish(new Timeout(State.CurrentState.Timeout));
         }
 
         private void Handle(Timeout timeout)
         {
-            if(NoHeartbeatSinceLastTimeout())
+            if (NoHeartbeatSinceLastTimeout())
             {
                 State = State.Handle(timeout);
             }
@@ -73,7 +71,7 @@ private bool AppendEntriesReceived()
 
         private bool NoHeartbeatSinceLastTimeout()
         {
-            if(!_appendEntriesIdsReceived.Any())
+            if (!_appendEntriesIdsReceived.Any())
             {
                 return true;
             }

src/Rafty/Concensus/RequestVoteResponse.cs

@@ -2,5 +2,11 @@ namespace Rafty.Concensus
 {
     public sealed class RequestVoteResponse
     {
+        public RequestVoteResponse(bool grant)
+        {
+            Grant = grant;
+        }
+
+        public bool Grant { get; private set; }
     }
 }