From 1c86f43f8451d2ecbe9f4099bdbc3031a9b56ecc Mon Sep 17 00:00:00 2001
From: Jordane Belanger <jordane.belanger@gmail.com>
Date: Tue, 17 Nov 2020 13:23:56 -0500
Subject: [PATCH] Update README.md

Fix Vapor 4 metrics endpoint example leading to an NIO leaky promise error at runtime in debug mode.
---
 README.md | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index cb63ae1..9455d83 100644
--- a/README.md
+++ b/README.md
@@ -111,7 +111,13 @@ By default, this should be accessible on your main serving port, at the `/metric
 ```swift
 app.get("metrics") { req -> EventLoopFuture<String> in
     let promise = req.eventLoop.makePromise(of: String.self)
-    try MetricsSystem.prometheus().collect(into: promise)
+    DispatchQueue.global().async {
+        do {
+            try MetricsSystem.prometheus().collect(into: promise)
+        } catch {
+            promise.fail(error)
+        }
+    }
     return promise.futureResult
 }
 ```