Added in support for the JSON RPC Eth Hashrate method. (#488)

Signed-off-by: Adrian Sutton <adrian.sutton@consensys.net>

ethereum/jsonrpc/src/main/java/tech/pegasys/pantheon/ethereum/jsonrpc/JsonRpcMethodsFactory.java

@@ -49,6 +49,7 @@ import tech.pegasys.pantheon.ethereum.jsonrpc.internal.methods.EthGetUncleByBloc
 import tech.pegasys.pantheon.ethereum.jsonrpc.internal.methods.EthGetUncleCountByBlockHash;
 import tech.pegasys.pantheon.ethereum.jsonrpc.internal.methods.EthGetUncleCountByBlockNumber;
 import tech.pegasys.pantheon.ethereum.jsonrpc.internal.methods.EthGetWork;
+import tech.pegasys.pantheon.ethereum.jsonrpc.internal.methods.EthHashrate;
 import tech.pegasys.pantheon.ethereum.jsonrpc.internal.methods.EthMining;
 import tech.pegasys.pantheon.ethereum.jsonrpc.internal.methods.EthNewBlockFilter;
 import tech.pegasys.pantheon.ethereum.jsonrpc.internal.methods.EthNewFilter;
@@ -182,6 +183,7 @@ public class JsonRpcMethodsFactory {
           new EthProtocolVersion(supportedCapabilities),
           new EthGasPrice(miningCoordinator),
           new EthGetWork(miningCoordinator),
+          new EthHashrate(miningCoordinator),
           new EthChainId(protocolSchedule.getChainId()));
     }
     if (rpcApis.contains(RpcApis.DEBUG)) {

ethereum/jsonrpc/src/main/java/tech/pegasys/pantheon/ethereum/jsonrpc/internal/methods/EthHashrate.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2018 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.pantheon.ethereum.jsonrpc.internal.methods;
+
+import tech.pegasys.pantheon.ethereum.blockcreation.MiningCoordinator;
+import tech.pegasys.pantheon.ethereum.jsonrpc.internal.JsonRpcRequest;
+import tech.pegasys.pantheon.ethereum.jsonrpc.internal.response.JsonRpcError;
+import tech.pegasys.pantheon.ethereum.jsonrpc.internal.response.JsonRpcErrorResponse;
+import tech.pegasys.pantheon.ethereum.jsonrpc.internal.response.JsonRpcResponse;
+import tech.pegasys.pantheon.ethereum.jsonrpc.internal.response.JsonRpcSuccessResponse;
+import tech.pegasys.pantheon.ethereum.jsonrpc.internal.results.Quantity;
+
+import java.util.Optional;
+
+public class EthHashrate implements JsonRpcMethod {
+
+  private final MiningCoordinator miningCoordinator;
+
+  public EthHashrate(final MiningCoordinator miningCoordinator) {
+    this.miningCoordinator = miningCoordinator;
+  }
+
+  @Override
+  public String getName() {
+    return "eth_hashrate";
+  }
+
+  @Override
+  public JsonRpcResponse response(final JsonRpcRequest req) {
+    try {
+      final Optional<Long> hashesPerSecond = miningCoordinator.hashesPerSecond();
+      if (hashesPerSecond.isPresent()) {
+        return new JsonRpcSuccessResponse(req.getId(), Quantity.create(hashesPerSecond.get()));
+      }
+      return new JsonRpcErrorResponse(req.getId(), JsonRpcError.NO_HASHES_PER_SECOND);
+    } catch (final UnsupportedOperationException ex) {
+      return new JsonRpcErrorResponse(req.getId(), JsonRpcError.INVALID_REQUEST);
+    }
+  }
+}

ethereum/jsonrpc/src/main/java/tech/pegasys/pantheon/ethereum/jsonrpc/internal/response/JsonRpcError.java

@@ -42,6 +42,7 @@ public enum JsonRpcError {
 
   // Miner failures
   COINBASE_NOT_SET(-32010, "Coinbase not set. Unable to start mining without a coinbase."),
+  NO_HASHES_PER_SECOND(-32011, "No hashes being generated by the current node."),
 
   // Wallet errors
   COINBASE_NOT_SPECIFIED(-32000, "Coinbase must be explicitly specified");

ethereum/jsonrpc/src/test/java/tech/pegasys/pantheon/ethereum/jsonrpc/internal/methods/EthHashrateTest.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright 2018 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.pantheon.ethereum.jsonrpc.internal.methods;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.when;
+
+import tech.pegasys.pantheon.ethereum.blockcreation.EthHashMiningCoordinator;
+import tech.pegasys.pantheon.ethereum.jsonrpc.internal.JsonRpcRequest;
+import tech.pegasys.pantheon.ethereum.jsonrpc.internal.response.JsonRpcError;
+import tech.pegasys.pantheon.ethereum.jsonrpc.internal.response.JsonRpcErrorResponse;
+import tech.pegasys.pantheon.ethereum.jsonrpc.internal.response.JsonRpcResponse;
+import tech.pegasys.pantheon.ethereum.jsonrpc.internal.response.JsonRpcSuccessResponse;
+
+import java.util.Optional;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+
+@RunWith(MockitoJUnitRunner.class)
+public class EthHashrateTest {
+
+  @Mock private EthHashMiningCoordinator miningCoordinator;
+  private EthHashrate method;
+  private final String JSON_RPC_VERSION = "2.0";
+  private final String ETH_METHOD = "eth_hashrate";
+
+  @Before
+  public void setUp() {
+    method = new EthHashrate(miningCoordinator);
+  }
+
+  @Test
+  public void returnsCorrectMethodName() {
+    assertThat(method.getName()).isEqualTo(ETH_METHOD);
+  }
+
+  @Test
+  public void shouldReturnValueFromMiningCoordinator() {
+    final JsonRpcRequest request = requestWithParams();
+    final JsonRpcResponse expectedResponse = new JsonRpcSuccessResponse(request.getId(), "0xc");
+    when(miningCoordinator.hashesPerSecond()).thenReturn(Optional.of(12L));
+
+    final JsonRpcResponse actualResponse = method.response(request);
+    assertThat(actualResponse).isEqualToComparingFieldByField(expectedResponse);
+  }
+
+  @Test
+  public void shouldReturnErrorWhenMiningCoordinatorDoesNotHaveHashes() {
+    final JsonRpcRequest request = requestWithParams();
+    final JsonRpcResponse expectedResponse =
+        new JsonRpcErrorResponse(request.getId(), JsonRpcError.NO_HASHES_PER_SECOND);
+    when(miningCoordinator.hashesPerSecond()).thenReturn(Optional.empty());
+
+    final JsonRpcResponse actualResponse = method.response(request);
+    assertThat(actualResponse).isEqualToComparingFieldByField(expectedResponse);
+  }
+
+  @Test
+  public void shouldReturnErrorWhenMiningCoordinatorDoesNotSupportHashing() {
+    final JsonRpcRequest request = requestWithParams();
+    final JsonRpcResponse expectedResponse =
+        new JsonRpcErrorResponse(request.getId(), JsonRpcError.INVALID_REQUEST);
+    when(miningCoordinator.hashesPerSecond()).thenThrow(UnsupportedOperationException.class);
+
+    final JsonRpcResponse actualResponse = method.response(request);
+    assertThat(actualResponse).isEqualToComparingFieldByField(expectedResponse);
+  }
+
+  private JsonRpcRequest requestWithParams() {
+    return new JsonRpcRequest(JSON_RPC_VERSION, ETH_METHOD, new Object[] {});
+  }
+}