fix: reset span name and http.route in static file middleware (#2856)

Author: lucacasonato

src/middlewares/static_files.ts

@@ -4,7 +4,7 @@ import type { MiddlewareFn } from "./mod.ts";
 import { ASSET_CACHE_BUST_KEY } from "../runtime/shared_internal.tsx";
 import { BUILD_ID } from "../runtime/build_id.ts";
 import { getBuildCache } from "../context.ts";
-import { tracer } from "../otel.ts";
+import { trace, tracer } from "../otel.ts";
 
 /**
  * Fresh middleware to enable file-system based routing.
@@ -41,6 +41,12 @@ export function staticFiles<T>(): MiddlewareFn<T> {
       return new Response("Method Not Allowed", { status: 405 });
     }
 
+    const parentSpan = trace.getActiveSpan();
+    if (parentSpan) {
+      parentSpan.updateName(`${req.method} /*`);
+      parentSpan.setAttribute("http.route", "/*");
+    }
+
     const span = tracer.startSpan("static file", {
       attributes: { "fresh.span_type": "static_file" },
       startTime,

src/otel.ts

@@ -4,3 +4,4 @@ import denoJson from "../deno.json" with { type: "json" };
 export const CURRENT_FRESH_VERSION = denoJson.version;
 
 export const tracer = trace.getTracer("fresh", CURRENT_FRESH_VERSION);
+export { trace };