mbproxy: initial commit through Phase 9 (TxId multiplexing)

Adds the mbproxy service end-to-end. Phases 00-08 implement the production-ready single-listener / 1:1-backend transparent Modbus TCP proxy with bidirectional BCD rewriting for the ~54-PLC DL205/DL260 fleet. Phase 9 replaces the connection layer with a single backend socket per PLC plus MBAP TxId rewriting, lifting the H2-ECOM100's 4-concurrent-client cap as an operational ceiling. Phase 9 additions of note: - PlcMultiplexer + UpstreamPipe + TxIdAllocator + CorrelationMap - InFlightRequest with IReadOnlyList<InterestedParty> (load-bearing for Phase 10 read coalescing — do not collapse to a single field) - Per-request watchdog: surfaces Modbus exception 0x0B to upstream on BackendRequestTimeoutMs, defending against lost responses, dead-PLC paths, and pymodbus 3.13.0's concurrent-multiplexed- request bug (its ServerRequestHandler.last_pdu state race) - Status DTO + HTML gain inFlight / maxInFlight / txIdWraps / disconnectCascades / queueDepth (Tier 1.6 in docs/kpi.md) Tests: 263 unit + 38 E2E. Multiplexer correctness under truly concurrent backend traffic is proved against a stub backend in PlcMultiplexerTests; MultiplexerE2ETests paces requests so pymodbus 3.13's single-PDU framer stays in known-good mode. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-14 01:49:35 -04:00
parent 2e937228a0
commit 56eee3c563
105 changed files with 18430 additions and 0 deletions
@@ -0,0 +1,196 @@
+using Mbproxy.Configuration;
+using Mbproxy.Options;
+using Xunit;
+
+namespace Mbproxy.Tests.Configuration;
+
+/// <summary>
+/// Unit tests for <see cref="ReloadPlan.Compute"/>.
+/// All tests verify the pure function logic — no side effects, no DI, no sockets.
+/// </summary>
+[Trait("Category", "Unit")]
+public sealed class ReloadPlanTests
+{
+    // ── Helpers ───────────────────────────────────────────────────────────────────────────
+
+    private static PlcOptions MakePlc(
+        string name, int listenPort, string host = "127.0.0.1", int port = 502)
+        => new() { Name = name, ListenPort = listenPort, Host = host, Port = port };
+
+    private static MbproxyOptions MakeOptions(
+        PlcOptions[] plcs,
+        BcdTagListOptions? global = null)
+        => new()
+        {
+            Plcs    = plcs,
+            BcdTags = global ?? new BcdTagListOptions(),
+        };
+
+    private static BcdTagListOptions GlobalWith(params (ushort addr, byte width)[] tags)
+        => new()
+        {
+            Global = tags.Select(t => new BcdTagOptions { Address = t.addr, Width = t.width }).ToList(),
+        };
+
+    // ── 1. Add one PLC ───────────────────────────────────────────────────────────────────
+
+    [Fact]
+    public void Compute_AddOnePlc_OnlyToAddPopulated()
+    {
+        var current = MakeOptions([MakePlc("A", 5020)]);
+        var next    = MakeOptions([MakePlc("A", 5020), MakePlc("B", 5021)]);
+
+        var plan = ReloadPlan.Compute(current, next);
+
+        Assert.Single(plan.ToAdd);
+        Assert.Equal("B", plan.ToAdd[0].Name);
+        Assert.Empty(plan.ToRemove);
+        Assert.Empty(plan.ToRestart);
+        Assert.Empty(plan.ToReseat);
+    }
+
+    // ── 2. Remove one PLC ────────────────────────────────────────────────────────────────
+
+    [Fact]
+    public void Compute_RemoveOnePlc_OnlyToRemovePopulated()
+    {
+        var current = MakeOptions([MakePlc("A", 5020), MakePlc("B", 5021)]);
+        var next    = MakeOptions([MakePlc("A", 5020)]);
+
+        var plan = ReloadPlan.Compute(current, next);
+
+        Assert.Empty(plan.ToAdd);
+        Assert.Single(plan.ToRemove);
+        Assert.Equal("B", plan.ToRemove[0]);
+        Assert.Empty(plan.ToRestart);
+        Assert.Empty(plan.ToReseat);
+    }
+
+    // ── 3. Changed ListenPort → goes to ToRestart, NOT ToReseat ──────────────────────────
+
+    [Fact]
+    public void Compute_ChangePort_GoesToToRestart_NotToReseat()
+    {
+        var current = MakeOptions([MakePlc("A", 5020)]);
+        var next    = MakeOptions([MakePlc("A", 5022)]);  // ListenPort changed
+
+        var plan = ReloadPlan.Compute(current, next);
+
+        Assert.Empty(plan.ToAdd);
+        Assert.Empty(plan.ToRemove);
+        Assert.Single(plan.ToRestart);
+        Assert.Equal("A", plan.ToRestart[0].Name);
+        Assert.Equal(5022, plan.ToRestart[0].New.ListenPort);
+        Assert.Empty(plan.ToReseat);
+    }
+
+    // ── 3b. Changed Host → goes to ToRestart ─────────────────────────────────────────────
+
+    [Fact]
+    public void Compute_ChangeHost_GoesToToRestart()
+    {
+        var current = MakeOptions([MakePlc("A", 5020, host: "10.0.0.1")]);
+        var next    = MakeOptions([MakePlc("A", 5020, host: "10.0.0.2")]);
+
+        var plan = ReloadPlan.Compute(current, next);
+
+        Assert.Single(plan.ToRestart);
+        Assert.Empty(plan.ToReseat);
+    }
+
+    // ── 4. Changed per-PLC tag override → goes to ToReseat ───────────────────────────────
+
+    [Fact]
+    public void Compute_ChangePerPlcTagOverride_GoesToToReseat()
+    {
+        var global = GlobalWith((1072, 16));
+
+        // Current: PLC-A has no overrides.
+        var current = MakeOptions([MakePlc("A", 5020)], global: global);
+
+        // Next: PLC-A adds address 1080.
+        var plcWithOverride = new PlcOptions
+        {
+            Name       = "A",
+            ListenPort = 5020,
+            Host       = "127.0.0.1",
+            Port       = 502,
+            BcdTags    = new PlcBcdOverrides
+            {
+                Add = [new BcdTagOptions { Address = 1080, Width = 16 }],
+            },
+        };
+        var next = new MbproxyOptions
+        {
+            Plcs    = [plcWithOverride],
+            BcdTags = global,
+        };
+
+        var plan = ReloadPlan.Compute(current, next);
+
+        Assert.Empty(plan.ToAdd);
+        Assert.Empty(plan.ToRemove);
+        Assert.Empty(plan.ToRestart);
+        Assert.Single(plan.ToReseat);
+        Assert.Equal("A", plan.ToReseat[0].Name);
+    }
+
+    // ── 5. Changed global tag list → all PLCs reseat, no restart ─────────────────────────
+
+    [Fact]
+    public void Compute_ChangeGlobalTagList_AllPlcsReseat_NoRestart()
+    {
+        var globalBefore = GlobalWith((1072, 16));
+        var globalAfter  = GlobalWith((1072, 16), (1080, 32));  // new 32-bit tag added
+
+        var current = MakeOptions([MakePlc("A", 5020), MakePlc("B", 5021)], global: globalBefore);
+        var next    = MakeOptions([MakePlc("A", 5020), MakePlc("B", 5021)], global: globalAfter);
+
+        var plan = ReloadPlan.Compute(current, next);
+
+        Assert.Empty(plan.ToAdd);
+        Assert.Empty(plan.ToRemove);
+        Assert.Empty(plan.ToRestart);
+        // Both PLCs should be reseated because the global tag list changed.
+        Assert.Equal(2, plan.ToReseat.Count);
+        Assert.Contains(plan.ToReseat, r => r.Name == "A");
+        Assert.Contains(plan.ToReseat, r => r.Name == "B");
+    }
+
+    // ── 6. No changes → all empty ────────────────────────────────────────────────────────
+
+    [Fact]
+    public void Compute_NoChanges_AllSectionsEmpty()
+    {
+        var global = GlobalWith((1072, 16));
+        var opts   = MakeOptions([MakePlc("A", 5020)], global: global);
+
+        var plan = ReloadPlan.Compute(opts, opts);
+
+        Assert.Empty(plan.ToAdd);
+        Assert.Empty(plan.ToRemove);
+        Assert.Empty(plan.ToRestart);
+        Assert.Empty(plan.ToReseat);
+    }
+
+    // ── 7. Connection options propagated ─────────────────────────────────────────────────
+
+    [Fact]
+    public void Compute_ConnectionOptions_AreFromNextSnapshot()
+    {
+        var current = new MbproxyOptions
+        {
+            Plcs = [MakePlc("A", 5020)],
+            Connection = new ConnectionOptions { BackendConnectTimeoutMs = 1000 },
+        };
+        var next = new MbproxyOptions
+        {
+            Plcs = [MakePlc("A", 5020)],
+            Connection = new ConnectionOptions { BackendConnectTimeoutMs = 9999 },
+        };
+
+        var plan = ReloadPlan.Compute(current, next);
+
+        Assert.Equal(9999, plan.Connection.BackendConnectTimeoutMs);
+    }
+}