Expose chain ID in the BlockchainService plugin API

CHANGELOG.md

@@ -16,6 +16,7 @@
 - Add configuration of Consolidation Request Contract Address via genesis configuration [#7647](https://github.com/hyperledger/besu/pull/7647)
 - Interrupt pending transaction processing on block creation timeout [#7673](https://github.com/hyperledger/besu/pull/7673)
 - Align gas cap calculation for transaction simulation to Geth approach [#7703](https://github.com/hyperledger/besu/pull/7703)
+- Expose chainId in the `BlockchainService` [7702](https://github.com/hyperledger/besu/pull/7702)
 
 ### Bug fixes
 - Fix mounted data path directory permissions for besu user [#7575](https://github.com/hyperledger/besu/pull/7575)

besu/src/main/java/org/hyperledger/besu/services/BlockchainServiceImpl.java

@@ -30,6 +30,7 @@
 import org.hyperledger.besu.plugin.data.TransactionReceipt;
 import org.hyperledger.besu.plugin.services.BlockchainService;
 
+import java.math.BigInteger;
 import java.util.List;
 import java.util.Optional;
 import java.util.function.Supplier;
@@ -182,4 +183,12 @@ public BlockBody getBlockBody() {
       }
     };
   }
+
+  @Override
+  public Optional<BigInteger> getChainId() {
+    if (protocolSchedule == null) {
+      return Optional.empty();
+    }
+    return protocolSchedule.getChainId();
+  }
 }

plugin-api/build.gradle

@@ -71,7 +71,7 @@ Calculated : ${currentHash}
 tasks.register('checkAPIChanges', FileStateChecker) {
   description = "Checks that the API for the Plugin-API project does not change without deliberate thought"
   files = sourceSets.main.allJava.files
-  knownHash = '5H+3gUzCwZtLByfnk11kf+kAPwykQ+WR+n3xWgyfsyY='
+  knownHash = '4jVaj9yW88nHbX0KmTR3dPQRvj9x8Pvh5E9Ry7KRT6w='
 }
 check.dependsOn('checkAPIChanges')
 

plugin-api/src/main/java/org/hyperledger/besu/plugin/services/BlockchainService.java

@@ -22,6 +22,7 @@
 import org.hyperledger.besu.plugin.data.BlockHeader;
 import org.hyperledger.besu.plugin.data.TransactionReceipt;
 
+import java.math.BigInteger;
 import java.util.List;
 import java.util.Optional;
 
@@ -106,5 +107,11 @@ void setFinalizedBlock(Hash blockHash)
    * @throws UnsupportedOperationException if the network is a PoS network
    */
   void setSafeBlock(Hash blockHash) throws IllegalArgumentException, UnsupportedOperationException;
-  ;
+
+  /**
+   * Get the chain id
+   *
+   * @return the chain id
+   */
+  Optional<BigInteger> getChainId();
 }