feat: add MonitorServer with /healthz and /varz endpoints

2026-02-22 22:20:44 -05:00
parent f6b38df291
commit f2badc3488
4 changed files with 289 additions and 0 deletions
--- a/tests/NATS.Server.Tests/MonitorTests.cs
+++ b/tests/NATS.Server.Tests/MonitorTests.cs
@@ -0,0 +1,98 @@
+using System.Net;
+using System.Net.Http.Json;
+using System.Net.Sockets;
+using Microsoft.Extensions.Logging.Abstractions;
+using NATS.Server.Monitoring;
+
+namespace NATS.Server.Tests;
+
+public class MonitorTests : IAsyncLifetime
+{
+    private readonly NatsServer _server;
+    private readonly int _natsPort;
+    private readonly int _monitorPort;
+    private readonly CancellationTokenSource _cts = new();
+    private readonly HttpClient _http = new();
+
+    public MonitorTests()
+    {
+        _natsPort = GetFreePort();
+        _monitorPort = GetFreePort();
+        _server = new NatsServer(
+            new NatsOptions { Port = _natsPort, MonitorPort = _monitorPort },
+            NullLoggerFactory.Instance);
+    }
+
+    public async Task InitializeAsync()
+    {
+        _ = _server.StartAsync(_cts.Token);
+        await _server.WaitForReadyAsync();
+        // Give monitoring server time to start
+        await Task.Delay(200);
+    }
+
+    public async Task DisposeAsync()
+    {
+        _http.Dispose();
+        await _cts.CancelAsync();
+        _server.Dispose();
+    }
+
+    [Fact]
+    public async Task Healthz_returns_ok()
+    {
+        var response = await _http.GetAsync($"http://127.0.0.1:{_monitorPort}/healthz");
+        response.StatusCode.ShouldBe(HttpStatusCode.OK);
+    }
+
+    [Fact]
+    public async Task Varz_returns_server_identity()
+    {
+        var response = await _http.GetAsync($"http://127.0.0.1:{_monitorPort}/varz");
+        response.StatusCode.ShouldBe(HttpStatusCode.OK);
+
+        var varz = await response.Content.ReadFromJsonAsync<Varz>();
+        varz.ShouldNotBeNull();
+        varz.Id.ShouldNotBeNullOrEmpty();
+        varz.Name.ShouldNotBeNullOrEmpty();
+        varz.Version.ShouldBe("0.1.0");
+        varz.Host.ShouldBe("0.0.0.0");
+        varz.Port.ShouldBe(_natsPort);
+        varz.MaxPayload.ShouldBe(1024 * 1024);
+        varz.Uptime.ShouldNotBeNullOrEmpty();
+        varz.Now.ShouldBeGreaterThan(DateTime.MinValue);
+        varz.Mem.ShouldBeGreaterThan(0);
+        varz.Cores.ShouldBeGreaterThan(0);
+    }
+
+    [Fact]
+    public async Task Varz_tracks_connections_and_messages()
+    {
+        // Connect a client and send a message
+        using var sock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
+        await sock.ConnectAsync(new IPEndPoint(IPAddress.Loopback, _natsPort));
+
+        var buf = new byte[4096];
+        _ = await sock.ReceiveAsync(buf, SocketFlags.None); // Read INFO
+
+        var cmd = "CONNECT {}\r\nSUB test 1\r\nPUB test 5\r\nhello\r\n"u8.ToArray();
+        await sock.SendAsync(cmd, SocketFlags.None);
+        await Task.Delay(200);
+
+        var response = await _http.GetAsync($"http://127.0.0.1:{_monitorPort}/varz");
+        var varz = await response.Content.ReadFromJsonAsync<Varz>();
+
+        varz.ShouldNotBeNull();
+        varz.Connections.ShouldBeGreaterThanOrEqualTo(1);
+        varz.TotalConnections.ShouldBeGreaterThanOrEqualTo(1UL);
+        varz.InMsgs.ShouldBeGreaterThanOrEqualTo(1L);
+        varz.InBytes.ShouldBeGreaterThanOrEqualTo(5L);
+    }
+
+    private static int GetFreePort()
+    {
+        using var sock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
+        sock.Bind(new IPEndPoint(IPAddress.Loopback, 0));
+        return ((IPEndPoint)sock.LocalEndPoint!).Port;
+    }
+}