feat(batch30): implement raft group-b snapshot helpers

2026-02-28 20:09:24 -05:00
parent 492030bd4b
commit ed1b62d6a3
3 changed files with 468 additions and 0 deletions
--- a/dotnet/tests/ZB.MOM.NatsNet.Server.Tests/JetStream/RaftNodeCoreTests.cs
+++ b/dotnet/tests/ZB.MOM.NatsNet.Server.Tests/JetStream/RaftNodeCoreTests.cs
@@ -0,0 +1,111 @@
+// Copyright 2012-2026 The NATS Authors
+// Licensed under the Apache License, Version 2.0
+
+using Shouldly;
+
+namespace ZB.MOM.NatsNet.Server.Tests.JetStream;
+
+public sealed class RaftNodeCoreTests
+{
+    [Fact]
+    public void SnapshotHelpers_WhenEncodedAndLoaded_ShouldRoundTrip()
+    {
+        var storeDir = Path.Combine(Path.GetTempPath(), $"raft-node-core-{Guid.NewGuid():N}");
+        var raft = new Raft
+        {
+            StoreDir = storeDir,
+            Term_ = 3,
+            Applied_ = 9,
+            PApplied = 7,
+            Wps = [1, 2, 3],
+        };
+
+        try
+        {
+            var checkpoint = raft.CreateSnapshotCheckpointLocked(force: true);
+            checkpoint.ShouldNotBeNull();
+
+            var snapshot = new Snapshot
+            {
+                LastTerm = 3,
+                LastIndex = 9,
+                PeerState = [7, 8],
+                Data = [9, 10, 11],
+            };
+
+            raft.InstallSnapshotInternal(snapshot).ShouldBeNull();
+            var (loaded, error) = raft.LoadLastSnapshot();
+            error.ShouldBeNull();
+            loaded.ShouldNotBeNull();
+            loaded!.LastTerm.ShouldBe(3UL);
+            loaded.LastIndex.ShouldBe(9UL);
+            loaded.PeerState.ShouldBe([7, 8]);
+            loaded.Data.ShouldBe([9, 10, 11]);
+
+            raft.SetupLastSnapshot().ShouldBeNull();
+            raft.PIndex.ShouldBe(9UL);
+            raft.PTerm.ShouldBe(3UL);
+        }
+        finally
+        {
+            if (Directory.Exists(storeDir))
+            {
+                Directory.Delete(storeDir, recursive: true);
+            }
+        }
+    }
+
+    [Fact]
+    public void LeadershipHelpers_WhenSteppingDownAndSelectingLeader_ShouldUpdateState()
+    {
+        var raft = new Raft
+        {
+            Id = "N1",
+            StateValue = (int)RaftState.Candidate,
+            Peers_ = new Dictionary<string, Lps>
+            {
+                ["N2"] = new() { Li = 3 },
+                ["N3"] = new() { Li = 7 },
+            },
+        };
+
+        raft.StepdownLocked("N3");
+        raft.State().ShouldBe(RaftState.Follower);
+        raft.LeaderId.ShouldBe("N3");
+        raft.SelectNextLeader().ShouldBe("N3");
+    }
+
+    [Fact]
+    public void CampaignHelpers_WhenLeaderOrFollower_ShouldReturnExpectedOutcome()
+    {
+        var raft = new Raft
+        {
+            StateValue = (int)RaftState.Leader,
+        };
+
+        raft.CampaignInternal(TimeSpan.FromMilliseconds(200)).ShouldNotBeNull();
+        raft.XferCampaign().ShouldNotBeNull();
+
+        raft.StateValue = (int)RaftState.Follower;
+        raft.CampaignInternal(TimeSpan.FromMilliseconds(200)).ShouldBeNull();
+        raft.State().ShouldBe(RaftState.Candidate);
+    }
+
+    [Fact]
+    public void ProgressHelpers_WhenCatchupAndKnownPeersChange_ShouldTrackFlags()
+    {
+        var raft = new Raft
+        {
+            Commit = 10,
+            Applied_ = 8,
+            Catchup = new CatchupState(),
+        };
+
+        raft.IsCatchingUp().ShouldBeTrue();
+        raft.IsCurrent(includeForwardProgress: true).ShouldBeFalse();
+        raft.Catchup = null;
+        raft.UpdateKnownPeersLocked(["N2", "N3"]);
+        raft.Peers_.Count.ShouldBe(2);
+        raft.RandCampaignTimeout().ShouldBeGreaterThan(TimeSpan.Zero);
+    }
+}