From adff43c0e21586fb23a8ec70c72b6889a79ae062 Mon Sep 17 00:00:00 2001
From: Philipp Kunz <gitlab@philkunz.com>
Date: Wed, 16 Oct 2024 02:22:44 +0200
Subject: [PATCH] fix(VirtualStream): Fix backpressure handling in
 VirtualStream workOnQueue method

---
 changelog.md                | 6 ++++++
 ts/00_commitinfo_data.ts    | 2 +-
 ts/classes.virtualstream.ts | 9 +++++++++
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/changelog.md b/changelog.md
index e072168..b9c431e 100644
--- a/changelog.md
+++ b/changelog.md
@@ -1,5 +1,11 @@
 # Changelog
 
+## 2024-10-16 - 3.1.6 - fix(VirtualStream)
+Fix backpressure handling in VirtualStream workOnQueue method
+
+- Resolved an issue in the workOnQueue method of VirtualStream where concurrent execution was not properly managed.
+- Introduced a workingDeferred promise to ensure proper queue handling and resolve potential race conditions.
+
 ## 2024-10-16 - 3.1.5 - fix(virtualstream)
 Add console log for debugging backpressure feedback loop
 
diff --git a/ts/00_commitinfo_data.ts b/ts/00_commitinfo_data.ts
index 1d892a1..b287c71 100644
--- a/ts/00_commitinfo_data.ts
+++ b/ts/00_commitinfo_data.ts
@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@api.global/typedrequest',
-  version: '3.1.5',
+  version: '3.1.6',
   description: 'A TypeScript library for making typed requests towards APIs, including facilities for handling requests, routing, and virtual stream handling.'
 }
diff --git a/ts/classes.virtualstream.ts b/ts/classes.virtualstream.ts
index 53cecd8..305b264 100644
--- a/ts/classes.virtualstream.ts
+++ b/ts/classes.virtualstream.ts
@@ -143,10 +143,17 @@ export class VirtualStream<T = Uint8Array> implements plugins.typedRequestInterf
 
   constructor() {}
 
+  workingDeferred: plugins.smartpromise.Deferred<void>;
+
   /**
    * takes care of sending 
    */
   private async workOnQueue() {
+    if (this.workingDeferred) {
+      return this.workingDeferred.promise;
+    } else {
+      this.workingDeferred = plugins.smartpromise.defer();
+    }
     if(this.side === 'requesting') {
       let thisSideIsBackpressured = !this.receiveBackpressuredArray.checkSpaceAvailable();
       let otherSideHasNext = false;
@@ -219,6 +226,8 @@ export class VirtualStream<T = Uint8Array> implements plugins.typedRequestInterf
       }
 
     }
+    this.workingDeferred.resolve();
+    this.workingDeferred = null;
   }
 
   /**