feat: ship agent-first mission control v0.2.57

backend/Controllers/BrowserTelemetryController.cs

@@ -0,0 +1,85 @@
+using System.Diagnostics;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.RateLimiting;
+using Nexus.Api.Models;
+using Nexus.Api.Observability;
+
+namespace Nexus.Api.Controllers;
+
+[Authorize]
+[ApiController]
+[Route("api/v1/telemetry/browser")]
+[EnableRateLimiting("agents")]
+public sealed class BrowserTelemetryController : ControllerBase
+{
+    private static readonly HashSet<string> AllowedNames =
+    [
+        "CLS",
+        "FCP",
+        "INP",
+        "LCP",
+        "TTFB",
+        "board_content_visible",
+        "board_delta_painted",
+        "mutation_confirmed",
+        "agent_proposal_readback"
+    ];
+
+    private static readonly HashSet<string> AllowedRatings =
+        ["good", "needs-improvement", "poor", "custom"];
+
+    [HttpPost]
+    public IResult Record([FromBody] BrowserMetricRequest request)
+    {
+        if (!AllowedNames.Contains(request.Name))
+            return Results.ValidationProblem(new Dictionary<string, string[]>
+            {
+                ["name"] = ["Unsupported browser metric."]
+            });
+
+        if (!double.IsFinite(request.Value) || request.Value < 0 || request.Value > 86_400_000)
+            return Results.ValidationProblem(new Dictionary<string, string[]>
+            {
+                ["value"] = ["Metric value must be finite and within the accepted range."]
+            });
+
+        if (!AllowedRatings.Contains(request.Rating))
+            return Results.ValidationProblem(new Dictionary<string, string[]>
+            {
+                ["rating"] = ["Unsupported metric rating."]
+            });
+
+        var route = NormalizeBoundedDimension(request.RouteName, "unknown", 80);
+        var liveMode = request.LiveMode is "live" or "polling" ? request.LiveMode : "unknown";
+        var navigationType = NormalizeBoundedDimension(request.NavigationType, "unknown", 40);
+
+        var tags = new TagList
+        {
+            { "metric.name", request.Name },
+            { "metric.rating", request.Rating },
+            { "route.name", route },
+            { "nexus.live_mode", liveMode },
+            { "navigation.type", navigationType }
+        };
+
+        if (request.Name == "CLS")
+            NexusTelemetry.BrowserScore.Record(request.Value, tags);
+        else
+            NexusTelemetry.BrowserDuration.Record(request.Value, tags);
+
+        return Results.NoContent();
+    }
+
+    private static string NormalizeBoundedDimension(string? value, string fallback, int maxLength)
+    {
+        if (string.IsNullOrWhiteSpace(value))
+            return fallback;
+
+        var normalized = new string(value
+            .Where(character => char.IsAsciiLetterOrDigit(character) || character is ' ' or '_' or '-')
+            .Take(maxLength)
+            .ToArray());
+        return string.IsNullOrWhiteSpace(normalized) ? fallback : normalized;
+    }
+}