chore: initial project import

backend/tests/Monitor.TestSupport/ChunkFactory.cs

@@ -0,0 +1,137 @@
+using System.Text.Json;
+using Fleet.Core;
+using Monitor.Protocol;
+
+namespace Monitor.TestSupport;
+
+/// <summary>每一个回显包的设定：上行或下行丢失，以及两个方向的单向时延（微秒）。</summary>
+public readonly record struct EchoPacket(bool LostUp, bool LostDown, long OwdUpUs, long OwdDownUs, long ProcessUs = 50);
+
+/// <summary>合成原始块：用于测试、模拟器和离线工具。块头里的时钟锚点保证 Probe 与 Agent 时钟相差 <see cref="ProbeOffsetUs"/>。</summary>
+public static class ChunkFactory
+{
+    /// <summary>合成块默认属于哪个 Probe（测试夹具在后端创建一个真实的 Probe 之后把它的 id 写在这里）。</summary>
+    public static string DefaultProbe { get; set; } = "prb_test";
+
+    public const long AgentMonoAnchorUs = 1_000_000_000;
+    public const long ProbeOffsetUs = 5_000_000;
+
+    public static RawChunkHeader Header(NodeId agent, string kind, long startUtcMs, int durationMs = 10_000, IReadOnlyDictionary<string, JsonElement>? parameters = null)
+    {
+        KindSpec spec = Kinds.Find(kind)!;
+        ParamResolution resolved = ParamResolver.Resolve(spec.Params, parameters);
+        return new RawChunkHeader
+        {
+            ChunkId = new ChunkId(Guid.CreateVersion7()),
+            Kind = kind,
+            AgentId = agent,
+            ProbeId = new ProbeId(DefaultProbe),
+            Params = new Dictionary<string, JsonElement>(resolved.Values!.Values),
+            Port = 7443,
+            StartUtcMs = startUtcMs,
+            DurationMs = durationMs,
+            Clock = new ChunkClock { AgentMonoUs = AgentMonoAnchorUs, UtcMs = startUtcMs, ProbeOffsetUs = ProbeOffsetUs },
+        };
+    }
+
+    /// <summary>Probe 时钟下，距离块起点 <paramref name="offsetMs"/> 毫秒的时刻（微秒）。</summary>
+    public static long ProbeUs(long offsetMs) => (offsetMs * 1000) + AgentMonoAnchorUs - ProbeOffsetUs;
+
+    public static long AgentUs(long offsetMs) => (offsetMs * 1000) + AgentMonoAnchorUs;
+
+    public static RawChunk Echo(
+        NodeId agent,
+        string kind,
+        long startUtcMs,
+        int count,
+        int intervalMs,
+        Func<int, EchoPacket> packet,
+        int durationMs = 10_000,
+        IReadOnlyDictionary<string, JsonElement>? parameters = null,
+        IEnumerable<RawStream>? extraStreams = null)
+    {
+        var msg = new StreamBuilder(Kinds.Find(kind)!.FindStream("msg")!);
+        for (int i = 0; i < count; i++)
+        {
+            EchoPacket p = packet(i);
+            long t1 = ProbeUs((long)i * intervalMs);
+            long t2 = t1 + ProbeOffsetUs + p.OwdUpUs;
+            long t3 = t2 + p.ProcessUs;
+            long t4 = t3 - ProbeOffsetUs + p.OwdDownUs;
+            msg.Add(i, 64, t1, p.LostUp ? null : t2, p.LostUp ? null : t3, p.LostUp || p.LostDown ? null : t4);
+        }
+
+        var streams = new List<RawStream> { msg.Build() };
+        if (extraStreams is not null)
+        {
+            streams.AddRange(extraStreams);
+        }
+
+        return new RawChunk(Header(agent, kind, startUtcMs, durationMs, parameters), streams);
+    }
+
+    /// <summary>10 Hz 的 udp_echo，没有丢包，RTT = 2 × owdMs。</summary>
+    public static RawChunk UdpEchoClean(NodeId agent, long startUtcMs, int count = 100, double owdMs = 20) =>
+        Echo(agent, "udp_echo", startUtcMs, count, 100, _ => new EchoPacket(false, false, (long)(owdMs * 1000), (long)(owdMs * 1000)));
+
+    public static RawStream TcpInfo(IEnumerable<(long TsUs, byte Side, uint SrttUs, uint RetransTotal, uint SegsOut)> samples)
+    {
+        var builder = new StreamBuilder(Kinds.TcpEcho.FindStream("tcp_info")!);
+        foreach ((long ts, byte side, uint srtt, uint retrans, uint segs) in samples)
+        {
+            builder.Add(ts, side, srtt, srtt / 4, 10, retrans, segs, segs * 100L);
+        }
+
+        return builder.Build();
+    }
+
+    public static RawChunk Connect(NodeId agent, long startUtcMs, IEnumerable<(long TcpUs, long? TlsUs, ConnectOutcomeCode Outcome)> attempts)
+    {
+        var builder = new StreamBuilder(Kinds.Connect.FindStream("conn")!);
+        int i = 0;
+        foreach ((long tcp, long? tls, ConnectOutcomeCode outcome) in attempts)
+        {
+            builder.Add(i, ProbeUs(i * 5000L), outcome == ConnectOutcomeCode.Timeout ? null : tcp, tls, (long)outcome);
+            i++;
+        }
+
+        return new RawChunk(Header(agent, "connect", startUtcMs), [builder.Build()]);
+    }
+
+    /// <summary>udp_train：Agent 以固定间隔发包，Probe 记录收到的时刻；<paramref name="lossEvery"/> 为 N 时每 N 个包丢一个。</summary>
+    public static RawChunk Train(NodeId agent, long startUtcMs, double mbps, int phase, int seconds = 10, int lossEvery = 0, long owdUs = 20_000)
+    {
+        const int size = 1250;
+        int packets = (int)(mbps * 1_000_000 / 8 / size * seconds);
+        double intervalUs = seconds * 1_000_000.0 / packets;
+        var pkt = new StreamBuilder(Kinds.UdpTrain.FindStream("pkt")!);
+        for (int i = 0; i < packets; i++)
+        {
+            long sendAgent = AgentMonoAnchorUs + (long)(i * intervalUs);
+            bool lost = lossEvery > 0 && i % lossEvery == 0;
+            long recvProbe = sendAgent + owdUs - ProbeOffsetUs;
+            pkt.Add(i, size, sendAgent, lost ? null : recvProbe);
+        }
+
+        var parameters = new Dictionary<string, JsonElement>
+        {
+            ["mbps"] = JsonSerializer.SerializeToElement(mbps, FactoryJson.Default.Double),
+            ["duration_s"] = JsonSerializer.SerializeToElement((double)seconds, FactoryJson.Default.Double),
+        };
+        RawChunkHeader header = Header(agent, "udp_train", startUtcMs, seconds * 1000, parameters);
+        header.Phase = phase;
+        header.TestId = new TestId("tst_test");
+        return new RawChunk(header, [pkt.Build(), new StreamBuilder(Kinds.UdpTrain.FindStream("step")!).Build()]);
+    }
+}
+
+public enum ConnectOutcomeCode
+{
+    Ok = 0,
+    Timeout = 1,
+    Reset = 2,
+    TlsAlert = 3,
+}
+
+[System.Text.Json.Serialization.JsonSerializable(typeof(double))]
+internal sealed partial class FactoryJson : System.Text.Json.Serialization.JsonSerializerContext;