From ca5a873bee1778d19c3acb98c74b7d9e84d2c31d Mon Sep 17 00:00:00 2001
From: Kevin Hahn <hahn.kev@gmail.com>
Date: Wed, 29 Nov 2023 16:23:45 +0700
Subject: [PATCH] enrich all traces with user id

---
 backend/LexBoxApi/Otel/OtelKernel.cs | 13 ++++++++++++-
 frontend/src/lib/otel/otel.client.ts | 10 +++++++++-
 frontend/src/lib/otel/otel.shared.ts |  2 +-
 3 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/backend/LexBoxApi/Otel/OtelKernel.cs b/backend/LexBoxApi/Otel/OtelKernel.cs
index 937389ff7..16872c494 100644
--- a/backend/LexBoxApi/Otel/OtelKernel.cs
+++ b/backend/LexBoxApi/Otel/OtelKernel.cs
@@ -4,6 +4,7 @@
 using LexBoxApi.Services;
 using LexCore.Auth;
 using Npgsql;
+using OpenTelemetry;
 using OpenTelemetry.Metrics;
 using OpenTelemetry.Resources;
 using OpenTelemetry.Trace;
@@ -28,6 +29,7 @@ public static void AddOpenTelemetryInstrumentation(this IServiceCollection servi
                     configuration.Bind("Otel", options);
                 })
                 .AddSource(ServiceName)
+                .AddProcessor<UserEnricher>()
                 .SetResourceBuilder(appResourceBuilder)
                 // could potentially add baggage to the trace as done in
                 // https://github.com/honeycombio/honeycomb-opentelemetry-dotnet/blob/main/src/Honeycomb.OpenTelemetry.Instrumentation.AspNetCore/TracerProviderBuilderExtensions.cs
@@ -109,6 +111,15 @@ private static void EnrichWithUser(this Activity activity, HttpContext httpConte
         {
             activity.SetTag("app.user.role", userRole);
         }
-        activity.SetTag("http.abort", httpContext.RequestAborted.IsCancellationRequested);
+        if (httpContext.RequestAborted.IsCancellationRequested)
+            activity.SetTag("http.abort", true);
+    }
+
+    private class UserEnricher(IHttpContextAccessor contextAccessor) : BaseProcessor<Activity>
+    {
+        public override void OnStart(Activity data)
+        {
+            if (contextAccessor.HttpContext is {} context) data.EnrichWithUser(context);
+        }
     }
 }
diff --git a/frontend/src/lib/otel/otel.client.ts b/frontend/src/lib/otel/otel.client.ts
index 90b8e8eda..bc0805d92 100644
--- a/frontend/src/lib/otel/otel.client.ts
+++ b/frontend/src/lib/otel/otel.client.ts
@@ -3,7 +3,7 @@ import { BatchSpanProcessor, WebTracerProvider } from '@opentelemetry/sdk-trace-
 import { APP_VERSION } from '$lib/util/version';
 import { OTLPTraceExporterBrowserWithXhrRetry } from './trace-exporter-browser-with-xhr-retry';
 import { Resource } from '@opentelemetry/resources'
-import { SERVICE_NAME } from '.'
+import {SERVICE_NAME, traceUserAttributes} from '.';
 import { SemanticResourceAttributes } from '@opentelemetry/semantic-conventions'
 import { ZoneContextManager } from '@opentelemetry/context-zone'
 import { getWebAutoInstrumentations } from '@opentelemetry/auto-instrumentations-web'
@@ -27,6 +27,14 @@ const resource = Resource.default().merge(
 const provider = new WebTracerProvider({
   resource: resource,
 });
+provider.addSpanProcessor({
+forceFlush: () => Promise.resolve(),
+  onStart: (span) => {
+    traceUserAttributes(span);
+  },
+  onEnd: () => {},
+  shutdown: () => Promise.resolve(),
+});
 const exporter = new OTLPTraceExporterBrowserWithXhrRetry({
   url: '/v1/traces'
 });
diff --git a/frontend/src/lib/otel/otel.shared.ts b/frontend/src/lib/otel/otel.shared.ts
index 48a4c331e..f492d6e2a 100644
--- a/frontend/src/lib/otel/otel.shared.ts
+++ b/frontend/src/lib/otel/otel.shared.ts
@@ -150,7 +150,7 @@ function getUser(event?: RequestEvent | NavigationEvent | Event): LexAuthUser |
     }
   }
 }
-function traceUserAttributes(span: Span, event?: RequestEvent | NavigationEvent | Event): void {
+export function traceUserAttributes(span: Span, event?: RequestEvent | NavigationEvent | Event): void {
     const user = getUser(event);
     if (user) {
         span.setAttribute('app.user.id', user.id);