Exclude empty requests and prepend request type byte in engine_getPayloadV4

Fixes ethereum/execution-apis#599 change to EIP-7685

Signed-off-by: Simon Dudley <[email protected]>

Author: siladu

ethereum/api/src/main/java/org/hyperledger/besu/ethereum/api/jsonrpc/internal/results/BlockResultFactory.java

@@ -167,7 +167,9 @@ public EngineGetPayloadResultV4 payloadTransactionCompleteV4(final PayloadWrappe
                 rqs ->
                     rqs.stream()
                         .sorted(Comparator.comparing(Request::getType))
-                        .map(r -> r.getData().toHexString())
+                        .filter(r -> !r.getData().isEmpty())
+                        .map(Request::getEncodedRequest)
+                        .map(Bytes::toHexString)
                         .toList());
 
     final BlobsBundleV1 blobsBundleV1 =

ethereum/api/src/test/java/org/hyperledger/besu/ethereum/api/jsonrpc/internal/methods/engine/EngineGetPayloadV4Test.java

@@ -147,7 +147,8 @@ header, new BlockBody(List.of(blobTx), emptyList(), Optional.of(emptyList()))),
     final List<String> requestsWithoutRequestId =
         requests.stream()
             .sorted(Comparator.comparing(Request::getType))
-            .map(r -> r.getData().toHexString())
+            .map(Request::getEncodedRequest)
+            .map(Bytes::toHexString)
             .toList();
     Optional.of(resp)
         .map(JsonRpcSuccessResponse.class::cast)
@@ -172,6 +173,53 @@ header, new BlockBody(List.of(blobTx), emptyList(), Optional.of(emptyList()))),
     verify(engineCallListener, times(1)).executionEngineCalled();
   }
 
+  @Test
+  public void shouldExcludeEmptyRequestsInRequestsList() {
+
+    BlockHeader header =
+        new BlockHeaderTestFixture().timestamp(pragueHardfork.milestone() + 1).buildHeader();
+    PayloadIdentifier payloadIdentifier =
+        PayloadIdentifier.forPayloadParams(
+            Hash.ZERO,
+            pragueHardfork.milestone(),
+            Bytes32.random(),
+            Address.fromHexString("0x42"),
+            Optional.empty(),
+            Optional.empty());
+
+    BlockWithReceipts block =
+        new BlockWithReceipts(
+            new Block(header, new BlockBody(emptyList(), emptyList(), Optional.of(emptyList()))),
+            emptyList());
+    final List<Request> unorderedRequests =
+        List.of(
+            new Request(RequestType.CONSOLIDATION, Bytes.of(1)),
+            new Request(RequestType.DEPOSIT, Bytes.of(1)),
+            new Request(RequestType.WITHDRAWAL, Bytes.EMPTY));
+    PayloadWrapper payload =
+        new PayloadWrapper(payloadIdentifier, block, Optional.of(unorderedRequests));
+
+    when(mergeContext.retrievePayloadById(payloadIdentifier)).thenReturn(Optional.of(payload));
+
+    final var resp = resp(RpcMethod.ENGINE_GET_PAYLOAD_V4.getMethodName(), payloadIdentifier);
+    assertThat(resp).isInstanceOf(JsonRpcSuccessResponse.class);
+
+    final List<String> expectedRequests =
+        List.of(
+            Bytes.concatenate(Bytes.of(RequestType.DEPOSIT.getSerializedType()), Bytes.of(1))
+                .toHexString(),
+            Bytes.concatenate(Bytes.of(RequestType.CONSOLIDATION.getSerializedType()), Bytes.of(1))
+                .toHexString());
+    Optional.of(resp)
+        .map(JsonRpcSuccessResponse.class::cast)
+        .ifPresent(
+            r -> {
+              assertThat(r.getResult()).isInstanceOf(EngineGetPayloadResultV4.class);
+              final EngineGetPayloadResultV4 res = (EngineGetPayloadResultV4) r.getResult();
+              assertThat(res.getExecutionRequests()).isEqualTo(expectedRequests);
+            });
+  }
+
   @Test
   public void shouldReturnUnsupportedFork() {
     final var resp = resp(RpcMethod.ENGINE_GET_PAYLOAD_V4.getMethodName(), mockPid);

ethereum/core/src/main/java/org/hyperledger/besu/ethereum/core/Request.java

@@ -29,4 +29,13 @@ public RequestType getType() {
   public Bytes getData() {
     return data();
   }
+
+  /**
+   * Gets the serialized form of the concatenated type and data.
+   *
+   * @return the serialized request as a byte.
+   */
+  public Bytes getEncodedRequest() {
+    return Bytes.concatenate(Bytes.of(getType().getSerializedType()), getData());
+  }
 }