Have HTTP client connection pool handle racy uncancellable timeout.

vietj · vietj · commit 5e5f8ee85698 · 2026-02-12T11:41:36.000+01:00
Motivation:

The HTTP client connection pool resource acquisition completion can race against the acquisition timeout.

Changes:

When the acquisition timeout cannot be cancelled, the resource should be recycled and the promise should not be completed.
diff --git a/vertx-core/src/main/java/io/vertx/core/http/impl/SharedHttpClientConnectionGroup.java b/vertx-core/src/main/java/io/vertx/core/http/impl/SharedHttpClientConnectionGroup.java
@@ -159,10 +159,11 @@ public void onConnect(PoolWaiter<HttpClientConnectionInternal> waiter) {
 
     @Override
     public void complete(Lease<HttpClientConnectionInternal> result, Throwable failure) {
-      if (timerID >= 0) {
-        context.owner().cancelTimer(timerID);
+      if (timerID >= 0 && !context.owner().cancelTimer(timerID)) {
+        result.recycle();
+      } else {
+        promise.complete(result, failure);
       }
-      promise.complete(result, failure);
     }
 
     void acquire() {

Original file line number	Diff line number	Diff line change
`@@ -159,10 +159,11 @@ public void onConnect(PoolWaiter<HttpClientConnectionInternal> waiter) {`
`159`	`159`
`160`	`160`	`@Override`
`161`	`161`	`public void complete(Lease<HttpClientConnectionInternal> result, Throwable failure) {`
`162`		`- if (timerID >= 0) {`
`163`		`- context.owner().cancelTimer(timerID);`
	`162`	`+ if (timerID >= 0 && !context.owner().cancelTimer(timerID)) {`
	`163`	`+ result.recycle();`
	`164`	`+ } else {`
	`165`	`+ promise.complete(result, failure);`
`164`	`166`	`}`
`165`		`- promise.complete(result, failure);`
`166`	`167`	`}`
`167`	`168`
`168`	`169`	`void acquire() {`