Removal of '#nullable disable' from the Libplanet.Net project (swarm)

CHANGES.md

@@ -15,6 +15,18 @@ To be released.
  -  Removed the '#nullable disable' from the Libplanet.Store project. [[#3644]]
  -  Removed the '#nullable disable' from the Libplanet.RocksDBStore project.
     [[#3651]]
+ -  (Libplanet.Net) Changed swarm-related types due to removal of
+    'nullable keyword'. [[#3670]]
+     - Changed `options` parameter type of `Swarm` class constructor from
+       `SwarmOptions` to `SwarmOptions?`.
+     - Changed `consensusTransport` parameter type of `Swarm` class constructor
+       from `ITransport` to `ITransport?`.
+     - Changed `Swarm.Validators` property type
+       from `IReadOnlyList<BoundPeer>` to `IReadOnlyList<BoundPeer>?`.
+     - Changed `progress` parameter type of `Swarm.PreloadAsync` method
+       from `IProgress<BlockSyncState>` to `IProgress<BlockSyncState>?`.
+     - Changed return type of `Swarm.FindSpecificPeerAsync` method
+       from `Task<BoundPeer>` to `Task<BoundPeer?>`.
 
 ### Backward-incompatible network protocol changes
 
@@ -45,6 +57,7 @@ To be released.
 [#3644]: https://github.com/planetarium/libplanet/pull/3644
 [#3651]: https://github.com/planetarium/libplanet/pull/3651
 [#3669]: https://github.com/planetarium/libplanet/pull/3669
+[#3670]: https://github.com/planetarium/libplanet/pull/3670
 
 
 Version 4.0.4

Libplanet.Net/Swarm.BlockCandidate.cs

@@ -1,4 +1,3 @@
-#nullable disable
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
@@ -19,7 +18,7 @@ public partial class Swarm
         private async Task ConsumeBlockCandidates(
             TimeSpan? checkInterval = null,
             bool render = true,
-            IProgress<BlockSyncState> progress = null,
+            IProgress<BlockSyncState>? progress = null,
             CancellationToken cancellationToken = default)
         {
             while (!cancellationToken.IsCancellationRequested)
@@ -63,10 +62,10 @@ private async Task ConsumeBlockCandidates(
         private bool BlockCandidateProcess(
             Branch candidate,
             bool render,
-            IProgress<BlockSyncState> progress,
+            IProgress<BlockSyncState>? progress,
             CancellationToken cancellationToken)
         {
-            BlockChain synced = null;
+            BlockChain? synced = null;
             System.Action renderSwap = () => { };
             try
             {
@@ -99,7 +98,7 @@ private bool BlockCandidateProcess(
             }
 
             if (synced is { } syncedB
-                && !syncedB.Id.Equals(BlockChain?.Id)
+                && !syncedB.Id.Equals(BlockChain.Id)
                 && BlockChain.Tip.Index < syncedB.Tip.Index)
             {
                 _logger.Debug(
@@ -126,15 +125,15 @@ private BlockChain AppendPreviousBlocks(
             BlockChain blockChain,
             Branch candidate,
             bool render,
-            IProgress<BlockSyncState> progress)
+            IProgress<BlockSyncState>? progress)
         {
             BlockChain workspace = blockChain;
             List<Guid> scope = new List<Guid>();
             bool forked = false;
 
             Block oldTip = workspace.Tip;
             Block newTip = candidate.Blocks.Last().Item1;
-            List<(Block, BlockCommit)> blocks = candidate.Blocks.ToList();
+            List<(Block, BlockCommit?)> blocks = candidate.Blocks.ToList();
             Block branchpoint = FindBranchpoint(
                  oldTip,
                  newTip,
@@ -429,7 +428,7 @@ private async Task<bool> BlockCandidateDownload(
                 return false;
             }
 
-            IAsyncEnumerable<(Block, BlockCommit)> blocksAsync = GetBlocksAsync(
+            IAsyncEnumerable<(Block, BlockCommit?)> blocksAsync = GetBlocksAsync(
                 peer,
                 hashes.Select(pair => pair.Item2),
                 cancellationToken);

Libplanet.Net/Swarm.BlockSync.cs

@@ -1,4 +1,3 @@
-#nullable disable
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -53,7 +52,7 @@ internal async Task PullBlocksAsync(
             TimeSpan? timeout,
             int maximumPollPeers,
             int chunkSize,
-            IProgress<BlockSyncState> progress,
+            IProgress<BlockSyncState>? progress,
             CancellationToken cancellationToken)
         {
             if (maximumPollPeers <= 0)
@@ -72,7 +71,7 @@ await GetPeersWithExcerpts(
         private async Task PullBlocksAsync(
             List<(BoundPeer, IBlockExcerpt)> peersWithBlockExcerpt,
             int chunkSize,
-            IProgress<BlockSyncState> progress,
+            IProgress<BlockSyncState>? progress,
             CancellationToken cancellationToken)
         {
             if (!peersWithBlockExcerpt.Any())
@@ -84,7 +83,7 @@ private async Task PullBlocksAsync(
             long totalBlocksToDownload = 0L;
             long receivedBlockCount = 0L;
             Block tempTip = BlockChain.Tip;
-            var blocks = new List<(Block, BlockCommit)>();
+            var blocks = new List<(Block, BlockCommit?)>();
 
             try
             {
@@ -142,15 +141,15 @@ private async Task PullBlocksAsync(
                     return;
                 }
 
-                IAsyncEnumerable<Tuple<Block, BlockCommit, BoundPeer>> completedBlocks =
+                IAsyncEnumerable<Tuple<Block, BlockCommit?, BoundPeer>> completedBlocks =
                     blockCompletion.Complete(
                         peers: peersWithBlockExcerpt.Select(pair => pair.Item1).ToList(),
                         blockFetcher: GetBlocksAsync,
                         cancellationToken: cancellationToken
                     );
 
                 await foreach (
-                    (Block block, BlockCommit commit, BoundPeer sourcePeer)
+                    (Block block, BlockCommit? commit, BoundPeer sourcePeer)
                     in completedBlocks.WithCancellation(cancellationToken))
                 {
                     _logger.Verbose(
@@ -208,13 +207,13 @@ in completedBlocks.WithCancellation(cancellationToken))
                 }
 
                 BlockHash? previousHash = blocks.First().Item1.PreviousHash;
-                Block branchpoint;
-                BlockCommit branchpointCommit;
+                Block? branchpoint;
+                BlockCommit? branchpointCommit;
                 if (previousHash != null)
                 {
                     branchpoint = BlockChain.Store.GetBlock(
                         (BlockHash)previousHash);
-                    branchpointCommit = BlockChain.GetBlockCommit(branchpoint.Hash);
+                    branchpointCommit = BlockChain.GetBlockCommit(branchpoint!.Hash);
                 }
                 else
                 {
@@ -321,7 +320,7 @@ await PullBlocksAsync(
             }
         }
 
-        private void OnBlockChainTipChanged(object sender, (Block OldTip, Block NewTip) e)
+        private void OnBlockChainTipChanged(object? sender, (Block OldTip, Block NewTip) e)
         {
             if (Running)
             {

Libplanet.Net/Swarm.MessageHandlers.cs

@@ -1,4 +1,3 @@
-#nullable disable
 using System;
 using System.Collections.Generic;
 using System.Linq;

Libplanet.Net/Swarm.cs

@@ -1,4 +1,3 @@
-#nullable disable
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
@@ -39,9 +38,9 @@ public partial class Swarm : IDisposable
 
         private readonly ILogger _logger;
         private readonly IStore _store;
-        private readonly ConsensusReactor _consensusReactor;
+        private readonly ConsensusReactor? _consensusReactor;
 
-        private CancellationTokenSource _workerCancellationTokenSource;
+        private CancellationTokenSource? _workerCancellationTokenSource;
         private CancellationToken _cancellationToken;
 
         private bool _disposed;
@@ -66,8 +65,8 @@ public Swarm(
             BlockChain blockChain,
             PrivateKey privateKey,
             ITransport transport,
-            SwarmOptions options = null,
-            ITransport consensusTransport = null,
+            SwarmOptions? options = null,
+            ITransport? consensusTransport = null,
             ConsensusReactorOption? consensusOption = null)
         {
             BlockChain = blockChain ?? throw new ArgumentNullException(nameof(blockChain));
@@ -95,7 +94,7 @@ public Swarm(
             // code, the portion initializing the swarm in Agent.cs in NineChronicles should be
             // fixed. for context, refer to
             // https://github.com/planetarium/libplanet/discussions/2303.
-            Transport = transport;
+            Transport = transport ?? throw new ArgumentNullException(nameof(transport));
             _processBlockDemandSessions = new ConcurrentDictionary<BoundPeer, int>();
             Transport.ProcessMessageHandler.Register(ProcessMessageHandlerAsync);
             PeerDiscovery = new KademliaProtocol(RoutingTable, Transport, Address);
@@ -138,11 +137,11 @@ public Swarm(
 
         public bool ConsensusRunning => _consensusReactor?.Running ?? false;
 
-        public DnsEndPoint EndPoint => AsPeer is BoundPeer boundPeer ? boundPeer.EndPoint : null;
+        public DnsEndPoint EndPoint => AsPeer.EndPoint;
 
         public Address Address => _privateKey.Address;
 
-        public BoundPeer AsPeer => Transport?.AsPeer;
+        public BoundPeer AsPeer => Transport.AsPeer;
 
         /// <summary>
         /// The last time when any message was arrived.
@@ -159,7 +158,7 @@ public Swarm(
         /// Returns list of the validators that consensus has in its routing table.
         /// If the node is not joining consensus, returns <c>null</c>.
         /// </summary>
-        public IReadOnlyList<BoundPeer> Validators => _consensusReactor?.Validators;
+        public IReadOnlyList<BoundPeer>? Validators => _consensusReactor?.Validators;
 
         /// <summary>
         /// The <see cref="BlockChain"/> instance this <see cref="Swarm"/> instance
@@ -183,7 +182,7 @@ public Swarm(
 
         internal TxCompletion<BoundPeer> TxCompletion { get; }
 
-        internal AsyncAutoResetEvent TxReceived => TxCompletion?.TxReceived;
+        internal AsyncAutoResetEvent TxReceived => TxCompletion.TxReceived;
 
         internal AsyncAutoResetEvent BlockHeaderReceived { get; }
 
@@ -200,23 +199,24 @@ public Swarm(
         internal SwarmOptions Options { get; }
 
         // FIXME: This should be exposed in a better way.
-        internal ConsensusReactor ConsensusReactor => _consensusReactor;
+        internal ConsensusReactor ConsensusReactor => _consensusReactor ??
+            throw new InvalidOperationException();
 
         /// <summary>
         /// Waits until this <see cref="Swarm"/> instance gets started to run.
         /// </summary>
         /// <seealso cref="ITransport.WaitForRunningAsync()"/>
         /// <returns>A <see cref="Task"/> completed when <see cref="ITransport.Running"/>
         /// property becomes <see langword="true"/>.</returns>
-        public Task WaitForRunningAsync() => Transport?.WaitForRunningAsync();
+        public Task WaitForRunningAsync() => Transport.WaitForRunningAsync();
 
         public void Dispose()
         {
             if (!_disposed)
             {
                 _workerCancellationTokenSource?.Cancel();
                 TxCompletion?.Dispose();
-                Transport?.Dispose();
+                Transport.Dispose();
                 _consensusReactor?.Dispose();
                 _workerCancellationTokenSource?.Dispose();
                 _disposed = true;
@@ -516,7 +516,7 @@ CancellationToken cancellationToken
         /// <exception cref="AggregateException">Thrown when the given the block downloading is
         /// failed.</exception>
         public async Task PreloadAsync(
-            IProgress<BlockSyncState> progress = null,
+            IProgress<BlockSyncState>? progress = null,
             CancellationToken cancellationToken = default)
         {
             await PreloadAsync(
@@ -556,7 +556,7 @@ await PreloadAsync(
         public async Task PreloadAsync(
             TimeSpan? dialTimeout,
             long tipDeltaThreshold,
-            IProgress<BlockSyncState> progress = null,
+            IProgress<BlockSyncState>? progress = null,
             CancellationToken cancellationToken = default)
         {
             using CancellationTokenRegistration ctr = cancellationToken.Register(() =>
@@ -663,7 +663,7 @@ await ConsumeBlockCandidates(
         /// A <see cref="BoundPeer"/> with <see cref="Address"/> of <paramref name="target"/>.
         /// Returns <see langword="null"/> if the peer with address does not exist.
         /// </returns>
-        public async Task<BoundPeer> FindSpecificPeerAsync(
+        public async Task<BoundPeer?> FindSpecificPeerAsync(
             Address target,
             int depth = 3,
             TimeSpan? timeout = null,
@@ -805,7 +805,7 @@ internal async IAsyncEnumerable<Tuple<long, BlockHash>> GetBlockHashes(
             throw new InvalidMessageContentException(errorMessage, parsedMessage.Content);
         }
 
-        internal async IAsyncEnumerable<(Block, BlockCommit)> GetBlocksAsync(
+        internal async IAsyncEnumerable<(Block, BlockCommit?)> GetBlocksAsync(
             BoundPeer peer,
             IEnumerable<BlockHash> blockHashes,
             [EnumeratorCancellation] CancellationToken cancellationToken
@@ -870,7 +870,7 @@ [EnumeratorCancellation] CancellationToken cancellationToken
                         cancellationToken.ThrowIfCancellationRequested();
                         Block block = BlockMarshaler.UnmarshalBlock(
                             (Bencodex.Types.Dictionary)Codec.Decode(blockPayload));
-                        BlockCommit commit = commitPayload.Length == 0
+                        BlockCommit? commit = commitPayload.Length == 0
                             ? null
                             : new BlockCommit(Codec.Decode(commitPayload));
 
@@ -985,7 +985,7 @@ internal async IAsyncEnumerable<Transaction> GetTxsAsync(
             BlockChain blockChain,
             IList<(BoundPeer, IBlockExcerpt)> peersWithExcerpts,
             int chunkSize = int.MaxValue,
-            IProgress<BlockSyncState> progress = null,
+            IProgress<BlockSyncState>? progress = null,
             [EnumeratorCancellation] CancellationToken cancellationToken = default
         )
         {
@@ -1008,7 +1008,7 @@ internal async IAsyncEnumerable<Transaction> GetTxsAsync(
                 int totalBlockHashesToDownload = -1;
                 int chunkBlockHashesToDownload = -1;
                 var pairsToYield = new List<Tuple<long, BlockHash>>();
-                Exception error = null;
+                Exception? error = null;
                 try
                 {
                     var downloaded = new List<BlockHash>();
@@ -1181,7 +1181,7 @@ private void BroadcastBlock(Address? except, Block block)
             BroadcastMessage(except, message);
         }
 
-        private void BroadcastTxs(BoundPeer except, IEnumerable<Transaction> txs)
+        private void BroadcastTxs(BoundPeer? except, IEnumerable<Transaction> txs)
         {
             List<TxId> txIds = txs.Select(tx => tx.Id).ToList();
             _logger.Information("Broadcasting {Count} txIds...", txIds.Count);
@@ -1221,7 +1221,7 @@ private void BroadcastMessage(Address? except, MessageContent message)
                     pair => pair.Item2 is { } chainStatus &&
                         genesisHash.Equals(chainStatus.GenesisHash) &&
                         chainStatus.TipIndex > tip.Index)
-                .Select(pair => (pair.Item1, (IBlockExcerpt)pair.Item2))
+                .Select(pair => (pair.Item1, (IBlockExcerpt)pair.Item2!))
                 .OrderByDescending(pair => pair.Item2.Index)
                 .ToList();
         }
@@ -1241,7 +1241,7 @@ private void BroadcastMessage(Address? except, MessageContent message)
         /// of <see cref="BoundPeer"/> and <see cref="ChainStatusMsg"/> where
         /// <see cref="ChainStatusMsg"/> can be <see langword="null"/> if dialing fails for
         /// a selected <see cref="BoundPeer"/>.</returns>
-        private Task<(BoundPeer, ChainStatusMsg)[]> DialExistingPeers(
+        private Task<(BoundPeer, ChainStatusMsg?)[]> DialExistingPeers(
             TimeSpan? dialTimeout,
             int maxPeersToDial,
             CancellationToken cancellationToken)
@@ -1268,15 +1268,15 @@ void LogException(BoundPeer peer, Task<Message> task)
             }
 
             var rnd = new System.Random();
-            IEnumerable<Task<(BoundPeer, ChainStatusMsg)>> tasks = Peers.OrderBy(_ => rnd.Next())
+            IEnumerable<Task<(BoundPeer, ChainStatusMsg?)>> tasks = Peers.OrderBy(_ => rnd.Next())
                 .Take(maxPeersToDial)
                 .Select(
                     peer => Transport.SendMessageAsync(
                         peer,
                         new GetChainStatusMsg(),
                         dialTimeout,
                         cancellationToken
-                    ).ContinueWith<(BoundPeer, ChainStatusMsg)>(
+                    ).ContinueWith<(BoundPeer, ChainStatusMsg?)>(
                         task =>
                         {
                             if (task.IsFaulted || task.IsCanceled ||
@@ -1300,7 +1300,7 @@ void LogException(BoundPeer peer, Task<Message> task)
                 {
                     if (task.IsFaulted)
                     {
-                        throw task.Exception;
+                        throw task.Exception!;
                     }
 
                     return task.Result.ToArray();