diagnose cov failure

Author: popduke

base-kv/base-kv-store-server/src/main/java/com/baidu/bifromq/basekv/store/range/KVRangeRestorer.java

@@ -73,13 +73,15 @@ public CompletableFuture<Void> restoreFrom(String leader, KVRangeSnapshot rangeS
         CompletableFuture<Void> onDone = session.doneFuture;
         try {
             IKVReseter restorer = range.toReseter(rangeSnapshot);
-            log.info("Restoring from snapshot: session={}, leader={} \n{}", session.id, leader, rangeSnapshot);
+            log.info("Restoring from snapshot: session={}, leader={}, restorer={} \n{}",
+                session.id, leader, restorer, rangeSnapshot);
             DisposableObserver<KVRangeMessage> observer = messenger.receive()
                 .filter(m -> m.hasSaveSnapshotDataRequest()
                     && m.getSaveSnapshotDataRequest().getSessionId().equals(session.id))
                 .timeout(idleTimeSec, TimeUnit.SECONDS)
                 .observeOn(Schedulers.from(executor))
                 .subscribeWith(new DisposableObserver<KVRangeMessage>() {
+                    private final IKVReseter reseter = restorer;
                     @Override
                     public void onNext(@NonNull KVRangeMessage m) {
                         SaveSnapshotDataRequest request = m.getSaveSnapshotDataRequest();
@@ -90,19 +92,19 @@ public void onNext(@NonNull KVRangeMessage m) {
                                     for (KVPair kv : request.getKvList()) {
                                         bytes += kv.getKey().size();
                                         bytes += kv.getValue().size();
-                                        restorer.put(kv.getKey(), kv.getValue());
+                                        reseter.put(kv.getKey(), kv.getValue());
                                     }
                                     metricManager.reportRestore(bytes);
                                     log.debug("Saved {} bytes snapshot data, send reply to {}: session={}",
                                         bytes, m.getHostStoreId(), session.id);
                                     if (request.getFlag() == SaveSnapshotDataRequest.Flag.End) {
                                         if (!onDone.isCancelled()) {
-                                            restorer.done();
+                                            reseter.done();
                                             dispose();
                                             onDone.complete(null);
                                             log.info("Restored from snapshot: session={}", session.id);
                                         } else {
-                                            restorer.abort();
+                                            reseter.abort();
                                             dispose();
                                             log.info("Snapshot restore canceled: session={}", session.id);
                                         }
@@ -136,8 +138,8 @@ public void onNext(@NonNull KVRangeMessage m) {
 
                     @Override
                     public void onError(@NonNull Throwable e) {
-                        if (restorer != null) {
-                            restorer.abort();
+                        if (reseter != null) {
+                            reseter.abort();
                         } else {
                             log.error("restorer is null", e);
                         }