From 1fd85b729d8928b84b9624b1c811372b426515ac Mon Sep 17 00:00:00 2001
From: Mononaut <github@monospace.live>
Date: Fri, 24 Mar 2023 09:47:08 +0900
Subject: [PATCH] handle stale transactions in block templates

---
 backend/src/api/disk-cache.ts     |  4 +++-
 backend/src/api/mempool-blocks.ts | 15 +++++++++++----
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/backend/src/api/disk-cache.ts b/backend/src/api/disk-cache.ts
index 7180c6f51..0ec502c08 100644
--- a/backend/src/api/disk-cache.ts
+++ b/backend/src/api/disk-cache.ts
@@ -43,7 +43,9 @@ class DiskCache {
       const mempool = memPool.getMempool();
       const mempoolArray: TransactionExtended[] = [];
       for (const tx in mempool) {
-        mempoolArray.push(mempool[tx]);
+        if (mempool[tx] && !mempool[tx].deleteAfter) {
+          mempoolArray.push(mempool[tx]);
+        }
       }
 
       Common.shuffleArray(mempoolArray);
diff --git a/backend/src/api/mempool-blocks.ts b/backend/src/api/mempool-blocks.ts
index 3c2feb0e2..ff502be24 100644
--- a/backend/src/api/mempool-blocks.ts
+++ b/backend/src/api/mempool-blocks.ts
@@ -151,7 +151,7 @@ class MempoolBlocks {
     // prepare a stripped down version of the mempool with only the minimum necessary data
     // to reduce the overhead of passing this data to the worker thread
     const strippedMempool: { [txid: string]: ThreadTransaction } = {};
-    Object.values(newMempool).forEach(entry => {
+    Object.values(newMempool).filter(tx => !tx.deleteAfter).forEach(entry => {
       strippedMempool[entry.txid] = {
         txid: entry.txid,
         fee: entry.fee,
@@ -186,7 +186,9 @@ class MempoolBlocks {
         this.txSelectionWorker?.once('error', reject);
       });
       this.txSelectionWorker.postMessage({ type: 'set', mempool: strippedMempool });
-      const { blocks, clusters } = await workerResultPromise;
+      let { blocks, clusters } = await workerResultPromise;
+      // filter out stale transactions
+      blocks = blocks.map(block => block.filter(tx => (tx.txid && tx.txid in newMempool)));
 
       // clean up thread error listener
       this.txSelectionWorker?.removeListener('error', threadErrorListener);
@@ -228,7 +230,9 @@ class MempoolBlocks {
         this.txSelectionWorker?.once('error', reject);
       });
       this.txSelectionWorker.postMessage({ type: 'update', added: addedStripped, removed });
-      const { blocks, clusters } = await workerResultPromise;
+      let { blocks, clusters } = await workerResultPromise;
+      // filter out stale transactions
+      blocks = blocks.map(block => block.filter(tx => (tx.txid && tx.txid in newMempool)));
 
       // clean up thread error listener
       this.txSelectionWorker?.removeListener('error', threadErrorListener);
@@ -243,7 +247,7 @@ class MempoolBlocks {
     // update this thread's mempool with the results
     blocks.forEach(block => {
       block.forEach(tx => {
-        if (tx.txid in mempool) {
+        if (tx.txid && tx.txid in mempool) {
           if (tx.effectiveFeePerVsize != null) {
             mempool[tx.txid].effectiveFeePerVsize = tx.effectiveFeePerVsize;
           }
@@ -253,6 +257,9 @@ class MempoolBlocks {
             const cluster = clusters[tx.cpfpRoot];
             let matched = false;
             cluster.forEach(txid => {
+              if (!txid || !mempool[txid]) {
+                return;
+              }
               if (txid === tx.txid) {
                 matched = true;
               } else {