Remove invalid tx from allTxs when seeing TxInvalid

Signed-off-by: Sasha Bogicevic <[email protected]>

Author: v0d1ch

hydra-node/src/Hydra/HeadLogic.hs

@@ -323,16 +323,6 @@ onOpenNetworkReqTx env ledger st ttl tx =
         | ttl > 0 ->
             wait (WaitOnNotApplicableTx err)
         | otherwise ->
-            -- XXX: We might want to remove invalid txs from allTxs here to
-            -- prevent them piling up infinitely. However, this is not really
-            -- covered by the spec and this could be problematic in case of
-            -- conflicting transactions paired with network latency and/or
-            -- message resubmission. For example: Assume tx2 depends on tx1, but
-            -- only tx2 is seen by a participant and eventually times out
-            -- because of network latency when receiving tx1. The leader,
-            -- however, saw both as valid and requests a snapshot including
-            -- both. This is a valid request and if we would have removed tx2
-            -- from allTxs, we would make the head stuck.
             newState TxInvalid{headId, utxo = localUTxO, transaction = tx, validationError = err}
 
   maybeRequestSnapshot nextSn outcome =
@@ -1783,7 +1773,10 @@ aggregate st = \case
       Open ost@OpenState{} -> Open ost{currentSlot = chainSlot}
       _otherState -> st
   IgnoredHeadInitializing{} -> st
-  TxInvalid{} -> st
+  TxInvalid{transaction} -> case st of
+    Open ost@OpenState{coordinatedHeadState = coordState@CoordinatedHeadState{allTxs = allTransactions}} ->
+      Open ost{coordinatedHeadState = coordState{allTxs = foldr Map.delete allTransactions [txId transaction]}}
+    _otherState -> st
   Checkpoint state' -> state'
 
 aggregateState ::