Improve transaction failure handling (#1598)

If Bolt exchange fails for whatever reason, subsequent runs should emit a failed transaction error.

Author: injectives

driver/src/main/java/org/neo4j/driver/internal/async/UnmanagedTransaction.java

@@ -320,7 +320,10 @@ public CompletionStage<Void> terminateAsync() {
 
     @Override
     public <T> T execute(Function<Throwable, T> causeOfTerminationConsumer) {
-        return executeWithLock(lock, () -> causeOfTerminationConsumer.apply(causeOfTermination));
+        return executeWithLock(lock, () -> {
+            var throwable = causeOfTermination == null ? null : failedTxException(causeOfTermination);
+            return causeOfTerminationConsumer.apply(throwable);
+        });
     }
 
     private void ensureCanRunQueries() {
@@ -347,15 +350,7 @@ private void ensureCanRunQueries() {
                 if (causeOfTermination instanceof TransactionTerminatedException transactionTerminatedException) {
                     throw transactionTerminatedException;
                 } else {
-                    var message =
-                            "Cannot run more queries in this transaction, it has either experienced an fatal error or was explicitly terminated";
-                    throw new TransactionTerminatedException(
-                            GqlStatusError.UNKNOWN.getStatus(),
-                            GqlStatusError.UNKNOWN.getStatusDescription(message),
-                            "N/A",
-                            message,
-                            GqlStatusError.DIAGNOSTIC_RECORD,
-                            causeOfTermination);
+                    throw failedTxException(causeOfTermination);
                 }
             } else if (commitFuture != null) {
                 var message = "Cannot run more queries in this transaction, it is being committed";
@@ -578,6 +573,18 @@ private CompletionStage<Void> closeAsync(boolean commit, boolean completeWithNul
         return stage;
     }
 
+    private static TransactionTerminatedException failedTxException(Throwable cause) {
+        var message =
+                "Cannot run more queries in this transaction, it has either experienced a fatal error or was explicitly terminated";
+        return new TransactionTerminatedException(
+                GqlStatusError.UNKNOWN.getStatus(),
+                GqlStatusError.UNKNOWN.getStatusDescription(message),
+                "N/A",
+                message,
+                GqlStatusError.DIAGNOSTIC_RECORD,
+                cause);
+    }
+
     private static class BeginResponseHandler implements DriverResponseHandler {
         final CompletableFuture<UnmanagedTransaction> summaryFuture = new CompletableFuture<>();
         private final ApiTelemetryWork apiTelemetryWork;

driver/src/test/java/org/neo4j/driver/integration/TransactionIT.java

@@ -422,7 +422,7 @@ void shouldPreventPullAfterTransactionTermination(boolean iterate) {
                     result.list();
                 }
             });
-            assertEquals(terminationException, exception);
+            assertEquals(terminationException, exception.getCause());
         }
         tx.close();
     }
@@ -441,8 +441,8 @@ void shouldPreventDiscardAfterTransactionTermination() {
 
         // Then
         for (var result : List.of(result0, result1)) {
-            var exception = assertThrows(ClientException.class, result::consume);
-            assertEquals(terminationException, exception);
+            var exception = assertThrows(TransactionTerminatedException.class, result::consume);
+            assertEquals(terminationException, exception.getCause());
         }
         tx.close();
     }

driver/src/test/java/org/neo4j/driver/integration/reactive/ReactiveTransactionIT.java

@@ -63,7 +63,7 @@ void shouldPreventPullAfterTransactionTermination() {
         for (var result : List.of(result0, result1)) {
             var exception = assertThrows(
                     ClientException.class, () -> Flux.from(result.records()).blockFirst());
-            assertEquals(terminationException, exception);
+            assertEquals(terminationException, exception.getCause());
         }
         Mono.fromDirect(tx.close()).block();
     }
@@ -92,7 +92,7 @@ void shouldPreventDiscardAfterTransactionTermination() {
         for (var result : List.of(result0, result1)) {
             var exception = assertThrows(ClientException.class, () -> Mono.fromDirect(result.consume())
                     .block());
-            assertEquals(terminationException, exception);
+            assertEquals(terminationException, exception.getCause());
         }
         Mono.fromDirect(tx.close()).block();
     }