Don't Create New Node Record If Discovery Is Disabled (#2140)

If peer discovery was disabled, we would still try to create a Node Record even though we hadn't initialized required fields.

Signed-off-by: Ratan Rai Sur <ratan.r.sur@gmail.com>

CHANGELOG.md

@@ -1,5 +1,17 @@
 # Changelog
 
+## 21.1.5
+
+### Additions and Improvements
+
+### Bug Fixes
+
+- Fixed `NullPointerException` when crossing network upgrade blocks when peer discovery is disabled. [\#2140](https://github.com/hyperledger/besu/pull/2140)
+
+### Early Access Features
+
+#### Previously identified known issues
+
 ## 21.1.4
 
 ### Additions and Improvements

ethereum/p2p/src/main/java/org/hyperledger/besu/ethereum/p2p/discovery/PeerDiscoveryAgent.java

@@ -176,7 +176,11 @@ public abstract class PeerDiscoveryAgent {
     }
   }
 
-  public NodeRecord updateNodeRecord() {
+  public void updateNodeRecord() {
+    if (!config.isActive()) {
+      return;
+    }
+
     final KeyValueStorage keyValueStorage =
         storageProvider.getStorageBySegmentIdentifier(KeyValueSegmentIdentifier.BLOCKCHAIN);
     final NodeRecordFactory nodeRecordFactory = NodeRecordFactory.DEFAULT;
@@ -232,7 +236,6 @@ public abstract class PeerDiscoveryAgent {
     localNode
         .orElseThrow(() -> new IllegalStateException("Local node should be set here"))
         .setNodeRecord(newNodeRecord);
-    return newNodeRecord;
   }
 
   public void addPeerRequirement(final PeerRequirement peerRequirement) {

ethereum/p2p/src/test/java/org/hyperledger/besu/ethereum/p2p/discovery/PeerDiscoveryAgentTest.java

@@ -16,6 +16,7 @@ package org.hyperledger.besu.ethereum.p2p.discovery;
 
 import static java.util.stream.Collectors.toList;
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatCode;
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
@@ -137,6 +138,28 @@ public class PeerDiscoveryAgentTest {
     assertThat(pre).isNotEqualTo(post);
   }
 
+  @Test
+  public void testNodeRecordNotUpdatedIfNoPeerDiscovery() {
+    KeyPair keyPair =
+        SIGNATURE_ALGORITHM
+            .get()
+            .createKeyPair(
+                SIGNATURE_ALGORITHM
+                    .get()
+                    .createPrivateKey(
+                        Bytes32.fromHexString(
+                            "0xb71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")));
+    final MockPeerDiscoveryAgent agent =
+        helper.startDiscoveryAgent(
+            helper
+                .agentBuilder()
+                .nodeKey(NodeKeyUtils.createFrom(keyPair))
+                .advertisedHost("127.0.0.1")
+                .bindPort(30303)
+                .active(false));
+    assertThatCode(agent::updateNodeRecord).doesNotThrowAnyException();
+  }
+
   @Test
   public void neighborsPacketFromUnbondedPeerIsDropped() {
     // Start an agent with no bootstrap peers.