From e1f97f76cc8cdf02fc8c02e02b3a4299d13c3fa5 Mon Sep 17 00:00:00 2001
From: Tim Fish <tim@timfish.uk>
Date: Fri, 7 Jun 2024 13:55:39 +0100
Subject: [PATCH] fix: `fetch('').catch()` triggers unhandled rejection in
 debugger (#15)

---
 src/index.ts | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/index.ts b/src/index.ts
index 218c0cb..8c2b5c2 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -76,6 +76,14 @@ function contentLengthFromResponseHeaders(headers: Buffer[]) {
   return undefined;
 }
 
+async function loadFetch() {
+  try {
+    await fetch('');
+  } catch (_) {
+    //
+  }
+}
+
 // A combination of https://github.com/elastic/apm-agent-nodejs and
 // https://github.com/gadget-inc/opentelemetry-instrumentations/blob/main/packages/opentelemetry-instrumentation-undici/src/index.ts
 export class FetchInstrumentation implements Instrumentation {
@@ -110,7 +118,7 @@ export class FetchInstrumentation implements Instrumentation {
 
   constructor(config: FetchInstrumentationConfig) {
     // Force load fetch API (since it's lazy loaded in Node 18)
-    fetch('').catch(() => {});
+    loadFetch();
     this.channelSubs = [];
     this.meter = metrics.getMeter(this.instrumentationName, this.instrumentationVersion);
     this.tracer = trace.getTracer(this.instrumentationName, this.instrumentationVersion);