implements engine_preparePayload and engine_getPayload (#4346)

ethereum/core/src/testFixtures/java/tech/pegasys/teku/core/BlockProposalTestUtil.java

@@ -85,7 +85,7 @@ public SignedBlockAndState createNewBlock(
                     .attesterSlashings(blockBodyLists.createAttesterSlashings())
                     .deposits(deposits)
                     .voluntaryExits(exits)
-                    .executionPayload(() -> createExecutionPayload(spec, blockSlotState)));
+                    .executionPayload(() -> getExecutionPayload(spec, blockSlotState)));
 
     // Sign block and set block signature
     final BeaconBlock block = newBlockAndState.getBlock();
@@ -128,16 +128,13 @@ private Eth1Data get_eth1_data_stub(BeaconState state, UInt64 current_epoch) {
         Hash.sha2_256(Hash.sha2_256(SSZ.encodeUInt64(votingPeriod.longValue()))));
   }
 
-  private static ExecutionPayload createExecutionPayload(Spec spec, BeaconState genericState) {
+  private static ExecutionPayload getExecutionPayload(Spec spec, BeaconState genericState) {
     final BeaconStateMerge state = BeaconStateMerge.required(genericState);
-    final Bytes32 executionParentHash = state.getLatest_execution_payload_header().getBlock_hash();
-    final UInt64 timestamp = spec.computeTimeAtSlot(state, state.getSlot());
 
     return spec.atSlot(state.getSlot())
         .getExecutionPayloadUtil()
         .orElseThrow()
-        .getExecutionPayload(
-            ExecutionEngineChannel.NOOP, executionParentHash, timestamp, UInt64.ZERO);
+        .getExecutionPayload(ExecutionEngineChannel.NOOP, UInt64.ZERO);
   }
 
   public int getProposerIndexForSlot(final BeaconState preState, final UInt64 slot) {

ethereum/spec/src/main/java/tech/pegasys/teku/spec/executionengine/ExecutionEngineChannel.java

@@ -21,20 +21,21 @@
 import tech.pegasys.teku.infrastructure.events.ChannelInterface;
 import tech.pegasys.teku.infrastructure.unsigned.UInt64;
 import tech.pegasys.teku.spec.datastructures.execution.ExecutionPayload;
+import tech.pegasys.teku.ssz.type.Bytes20;
 
 public interface ExecutionEngineChannel extends ChannelInterface {
 
   ExecutionEngineChannel NOOP =
       new ExecutionEngineChannel() {
 
         @Override
-        public SafeFuture<Void> prepareBlock(
-            Bytes32 parentHash, UInt64 timestamp, UInt64 payloadId) {
-          return SafeFuture.completedFuture(null);
+        public SafeFuture<UInt64> preparePayload(
+            Bytes32 parentHash, UInt64 timestamp, Bytes32 random, Bytes20 feeRecipient) {
+          return SafeFuture.completedFuture(UInt64.ZERO);
         }
 
         @Override
-        public SafeFuture<ExecutionPayload> assembleBlock(Bytes32 parentHash, UInt64 timestamp) {
+        public SafeFuture<ExecutionPayload> getPayload(UInt64 payloadId) {
           return SafeFuture.completedFuture(new ExecutionPayload());
         }
 
@@ -64,16 +65,10 @@ public SafeFuture<Block> getPowChainHead() {
         }
       };
 
-  SafeFuture<Void> prepareBlock(Bytes32 parentHash, UInt64 timestamp, UInt64 payloadId);
+  SafeFuture<UInt64> preparePayload(
+      Bytes32 parentHash, UInt64 timestamp, Bytes32 random, Bytes20 feeRecipient);
 
-  /**
-   * Requests execution-engine to produce a block.
-   *
-   * @param parentHash the hash of execution block to produce atop of
-   * @param timestamp the timestamp of the beginning of the slot
-   * @return a response with execution payload
-   */
-  SafeFuture<ExecutionPayload> assembleBlock(Bytes32 parentHash, UInt64 timestamp);
+  SafeFuture<ExecutionPayload> getPayload(UInt64 payloadId);
 
   /**
    * Requests execution-engine to process a block.

ethereum/spec/src/main/java/tech/pegasys/teku/spec/logic/common/util/ExecutionPayloadUtil.java

@@ -19,6 +19,7 @@
 import tech.pegasys.teku.infrastructure.unsigned.UInt64;
 import tech.pegasys.teku.spec.datastructures.execution.ExecutionPayload;
 import tech.pegasys.teku.spec.executionengine.ExecutionEngineChannel;
+import tech.pegasys.teku.ssz.type.Bytes20;
 
 public class ExecutionPayloadUtil {
 
@@ -30,19 +31,21 @@ public boolean verifyExecutionStateTransition(
     return executionEngineChannel.newBlock(executionPayload).join();
   }
 
-  public void prepareExecutionPayload(
+  public UInt64 prepareExecutionPayload(
       ExecutionEngineChannel executionEngineChannel,
       Bytes32 parentHash,
       UInt64 timestamp,
-      UInt64 payloadId) {
-    executionEngineChannel.prepareBlock(parentHash, timestamp, payloadId).join();
+      Bytes32 random,
+      Bytes20 feeRecipient) {
+
+    return executionEngineChannel
+        .preparePayload(parentHash, timestamp, random, feeRecipient)
+        .join();
   }
 
   public ExecutionPayload getExecutionPayload(
-      ExecutionEngineChannel executionEngineChannel,
-      Bytes32 parentHash,
-      UInt64 timestamp,
-      UInt64 payloadId) {
-    return executionEngineChannel.assembleBlock(parentHash, timestamp).join();
+      ExecutionEngineChannel executionEngineChannel, UInt64 payloadId) {
+
+    return executionEngineChannel.getPayload(payloadId).join();
   }
 }

services/powchain/src/main/java/tech/pegasys/teku/services/powchain/execution/ExecutionEngineChannelImpl.java

@@ -29,11 +29,13 @@
 import tech.pegasys.teku.infrastructure.unsigned.UInt64;
 import tech.pegasys.teku.services.powchain.execution.client.ExecutionEngineClient;
 import tech.pegasys.teku.services.powchain.execution.client.Web3JExecutionEngineClient;
-import tech.pegasys.teku.services.powchain.execution.client.schema.AssembleBlockRequest;
 import tech.pegasys.teku.services.powchain.execution.client.schema.ExecutionPayload;
 import tech.pegasys.teku.services.powchain.execution.client.schema.NewBlockResponse;
+import tech.pegasys.teku.services.powchain.execution.client.schema.PreparePayloadRequest;
+import tech.pegasys.teku.services.powchain.execution.client.schema.PreparePayloadResponse;
 import tech.pegasys.teku.services.powchain.execution.client.schema.Response;
 import tech.pegasys.teku.spec.executionengine.ExecutionEngineChannel;
+import tech.pegasys.teku.ssz.type.Bytes20;
 
 public class ExecutionEngineChannelImpl implements ExecutionEngineChannel {
 
@@ -66,24 +68,34 @@ private static void printConsole(String formatString, Object... args) {
   }
 
   @Override
-  public SafeFuture<Void> prepareBlock(Bytes32 parentHash, UInt64 timestamp, UInt64 payloadId) {
-    return SafeFuture.completedFuture(null);
+  public SafeFuture<UInt64> preparePayload(
+      Bytes32 parentHash, UInt64 timestamp, Bytes32 random, Bytes20 feeRecipient) {
+    return executionEngineClient
+        .preparePayload(new PreparePayloadRequest(parentHash, timestamp, random, feeRecipient))
+        .thenApply(ExecutionEngineChannelImpl::unwrapResponseOrThrow)
+        .thenApply(PreparePayloadResponse::getPayloadId)
+        .thenPeek(
+            getPayloadId ->
+                printConsole(
+                    "engine_preparePayload(parentHash=%s, timestamp=%s, random=%s, feeRecipient=%s) ~> %s",
+                    LogFormatter.formatHashRoot(parentHash),
+                    timestamp.toString(),
+                    LogFormatter.formatHashRoot(random),
+                    feeRecipient.toHexString(),
+                    getPayloadId));
   }
 
   @Override
-  public SafeFuture<tech.pegasys.teku.spec.datastructures.execution.ExecutionPayload> assembleBlock(
-      Bytes32 parentHash, UInt64 timestamp) {
-    AssembleBlockRequest request = new AssembleBlockRequest(parentHash, timestamp);
+  public SafeFuture<tech.pegasys.teku.spec.datastructures.execution.ExecutionPayload> getPayload(
+      UInt64 payloadId) {
 
     return executionEngineClient
-        .consensusAssembleBlock(request)
+        .getPayload(payloadId)
         .thenApply(ExecutionEngineChannelImpl::unwrapResponseOrThrow)
         .thenApply(ExecutionPayload::asInternalExecutionPayload)
         .thenPeek(
             executionPayload ->
-                printConsole(
-                    "consensus_assembleBlock(parent_hash=%s, timestamp=%s) ~> %s",
-                    LogFormatter.formatHashRoot(parentHash), timestamp, executionPayload));
+                printConsole("engine_getPayload(payloadId=%s) ~> %s", payloadId, executionPayload));
   }
 
   @Override

services/powchain/src/main/java/tech/pegasys/teku/services/powchain/execution/client/ExecutionEngineClient.java

@@ -20,16 +20,19 @@
 import org.web3j.protocol.core.methods.response.EthBlock;
 import tech.pegasys.teku.infrastructure.async.SafeFuture;
 import tech.pegasys.teku.infrastructure.unsigned.UInt64;
-import tech.pegasys.teku.services.powchain.execution.client.schema.AssembleBlockRequest;
 import tech.pegasys.teku.services.powchain.execution.client.schema.ExecutionPayload;
 import tech.pegasys.teku.services.powchain.execution.client.schema.GenericResponse;
 import tech.pegasys.teku.services.powchain.execution.client.schema.NewBlockResponse;
+import tech.pegasys.teku.services.powchain.execution.client.schema.PreparePayloadRequest;
+import tech.pegasys.teku.services.powchain.execution.client.schema.PreparePayloadResponse;
 import tech.pegasys.teku.services.powchain.execution.client.schema.Response;
 import tech.pegasys.teku.ssz.type.Bytes20;
 
 public interface ExecutionEngineClient {
 
-  SafeFuture<Response<ExecutionPayload>> consensusAssembleBlock(AssembleBlockRequest request);
+  SafeFuture<Response<PreparePayloadResponse>> preparePayload(PreparePayloadRequest request);
+
+  SafeFuture<Response<ExecutionPayload>> getPayload(UInt64 payloadId);
 
   SafeFuture<Response<NewBlockResponse>> consensusNewBlock(ExecutionPayload request);
 
@@ -45,15 +48,27 @@ public interface ExecutionEngineClient {
       new ExecutionEngineClient() {
         private final Bytes ZERO_LOGS_BLOOM = Bytes.wrap(new byte[256]);
         private UInt64 number = UInt64.ZERO;
+        private UInt64 payloadId = UInt64.ZERO;
+        private Optional<PreparePayloadRequest> lastPreparePayloadRequest = Optional.empty();
+
+        @Override
+        public SafeFuture<Response<PreparePayloadResponse>> preparePayload(
+            PreparePayloadRequest request) {
+          lastPreparePayloadRequest = Optional.of(request);
+          payloadId = payloadId.increment();
+          return SafeFuture.completedFuture(new Response<>(new PreparePayloadResponse(payloadId)));
+        }
 
         @Override
-        public SafeFuture<Response<ExecutionPayload>> consensusAssembleBlock(
-            AssembleBlockRequest request) {
+        public SafeFuture<Response<ExecutionPayload>> getPayload(UInt64 payloadId) {
+          PreparePayloadRequest preparePayloadRequest =
+              lastPreparePayloadRequest.orElseThrow(
+                  () -> new IllegalStateException("preparePayload was not called."));
           number = number.increment();
           return SafeFuture.completedFuture(
               new Response<>(
                   new ExecutionPayload(
-                      request.parentHash,
+                      preparePayloadRequest.parentHash,
                       Bytes20.ZERO,
                       Bytes32.ZERO,
                       Bytes32.ZERO,
@@ -62,7 +77,7 @@ public SafeFuture<Response<ExecutionPayload>> consensusAssembleBlock(
                       number,
                       UInt64.ZERO,
                       UInt64.ZERO,
-                      request.timestamp,
+                      preparePayloadRequest.timestamp,
                       Bytes32.ZERO,
                       Bytes32.random(),
                       Arrays.asList(Bytes.random(128), Bytes.random(256), Bytes.random(512)))));

services/powchain/src/main/java/tech/pegasys/teku/services/powchain/execution/client/Web3JExecutionEngineClient.java

@@ -23,10 +23,12 @@
 import org.web3j.protocol.core.methods.response.EthBlock;
 import org.web3j.protocol.http.HttpService;
 import tech.pegasys.teku.infrastructure.async.SafeFuture;
-import tech.pegasys.teku.services.powchain.execution.client.schema.AssembleBlockRequest;
+import tech.pegasys.teku.infrastructure.unsigned.UInt64;
 import tech.pegasys.teku.services.powchain.execution.client.schema.ExecutionPayload;
 import tech.pegasys.teku.services.powchain.execution.client.schema.GenericResponse;
 import tech.pegasys.teku.services.powchain.execution.client.schema.NewBlockResponse;
+import tech.pegasys.teku.services.powchain.execution.client.schema.PreparePayloadRequest;
+import tech.pegasys.teku.services.powchain.execution.client.schema.PreparePayloadResponse;
 import tech.pegasys.teku.services.powchain.execution.client.schema.Response;
 
 public class Web3JExecutionEngineClient implements ExecutionEngineClient {
@@ -40,14 +42,25 @@ public Web3JExecutionEngineClient(String eth1Endpoint) {
   }
 
   @Override
-  public SafeFuture<Response<ExecutionPayload>> consensusAssembleBlock(
-      AssembleBlockRequest request) {
-    Request<?, AssembleBlockWeb3jResponse> web3jRequest =
+  public SafeFuture<Response<PreparePayloadResponse>> preparePayload(
+      PreparePayloadRequest request) {
+    Request<?, PreparePayloadWeb3jResponse> web3jRequest =
         new Request<>(
-            "consensus_assembleBlock",
+            "engine_preparePayload",
             Collections.singletonList(request),
             web3jService,
-            AssembleBlockWeb3jResponse.class);
+            PreparePayloadWeb3jResponse.class);
+    return doRequest(web3jRequest);
+  }
+
+  @Override
+  public SafeFuture<Response<ExecutionPayload>> getPayload(UInt64 payloadId) {
+    Request<?, GetPayloadWeb3jResponse> web3jRequest =
+        new Request<>(
+            "engine_getPayload",
+            Collections.singletonList(payloadId.toString()),
+            web3jService,
+            GetPayloadWeb3jResponse.class);
     return doRequest(web3jRequest);
   }
 
@@ -117,8 +130,10 @@ private <T> SafeFuture<Response<T>> doRequest(
     return SafeFuture.of(responseFuture);
   }
 
-  static class AssembleBlockWeb3jResponse
-      extends org.web3j.protocol.core.Response<ExecutionPayload> {}
+  static class GetPayloadWeb3jResponse extends org.web3j.protocol.core.Response<ExecutionPayload> {}
+
+  static class PreparePayloadWeb3jResponse
+      extends org.web3j.protocol.core.Response<PreparePayloadResponse> {}
 
   static class NewBlockWeb3jResponse extends org.web3j.protocol.core.Response<NewBlockResponse> {}
 

services/powchain/src/main/java/tech/pegasys/teku/services/powchain/execution/client/schema/PreparePayloadRequest.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2021 ConsenSys AG.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+ * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License.
+ */
+
+package tech.pegasys.teku.services.powchain.execution.client.schema;
+
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+import java.util.Objects;
+import org.apache.tuweni.bytes.Bytes32;
+import tech.pegasys.teku.infrastructure.unsigned.UInt64;
+import tech.pegasys.teku.services.powchain.execution.client.serializer.BytesSerializer;
+import tech.pegasys.teku.services.powchain.execution.client.serializer.UInt64AsHexSerializer;
+import tech.pegasys.teku.ssz.type.Bytes20;
+
+public class PreparePayloadRequest {
+  @JsonSerialize(using = BytesSerializer.class)
+  public final Bytes32 parentHash;
+
+  @JsonSerialize(using = UInt64AsHexSerializer.class)
+  public final UInt64 timestamp;
+
+  @JsonSerialize(using = BytesSerializer.class)
+  public final Bytes32 random;
+
+  @JsonSerialize(using = BytesSerializer.class)
+  public final Bytes20 feeRecipient;
+
+  public PreparePayloadRequest(
+      Bytes32 parentHash, UInt64 timestamp, Bytes32 random, Bytes20 feeRecipient) {
+    this.parentHash = parentHash;
+    this.timestamp = timestamp;
+    this.random = random;
+    this.feeRecipient = feeRecipient;
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    PreparePayloadRequest that = (PreparePayloadRequest) o;
+    return Objects.equals(parentHash, that.parentHash)
+        && Objects.equals(timestamp, that.timestamp)
+        && Objects.equals(random, that.random)
+        && Objects.equals(feeRecipient, that.feeRecipient);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(parentHash, timestamp, random, feeRecipient);
+  }
+
+  @Override
+  public String toString() {
+    return "PreparePayloadRequest{"
+        + "parentHash="
+        + parentHash
+        + ", timestamp="
+        + timestamp
+        + ", random="
+        + random
+        + ", feeRecipient="
+        + feeRecipient
+        + '}';
+  }
+}