add correct default to rpcHost (#7725)

---------

Signed-off-by: Sally MacFarlane <macfarla.github@gmail.com>
Co-authored-by: Simon Dudley <simon.dudley@consensys.net>

besu/src/main/java/org/hyperledger/besu/cli/options/stable/JsonRpcHttpOptions.java

@@ -15,6 +15,7 @@
 package org.hyperledger.besu.cli.options.stable;
 
 import static java.util.Arrays.asList;
+import static org.hyperledger.besu.ethereum.api.jsonrpc.JsonRpcConfiguration.DEFAULT_JSON_RPC_HOST;
 import static org.hyperledger.besu.ethereum.api.jsonrpc.JsonRpcConfiguration.DEFAULT_JSON_RPC_PORT;
 import static org.hyperledger.besu.ethereum.api.jsonrpc.JsonRpcConfiguration.DEFAULT_PRETTY_JSON_ENABLED;
 import static org.hyperledger.besu.ethereum.api.jsonrpc.RpcApis.DEFAULT_RPC_APIS;
@@ -65,7 +66,7 @@ public class JsonRpcHttpOptions {
       paramLabel = DefaultCommandValues.MANDATORY_HOST_FORMAT_HELP,
       description = "Host for JSON-RPC HTTP to listen on (default: ${DEFAULT-VALUE})",
       arity = "1")
-  private String rpcHttpHost;
+  private String rpcHttpHost = DEFAULT_JSON_RPC_HOST;
 
   @CommandLine.Option(
       names = {"--rpc-http-port"},

besu/src/test/java/org/hyperledger/besu/cli/BesuCommandTest.java

@@ -1029,6 +1029,12 @@ public class BesuCommandTest extends CommandTestAbstract {
 
     assertThat(commandOutput.toString(UTF_8)).isEmpty();
     assertThat(commandErrorOutput.toString(UTF_8)).isEmpty();
+
+    // rpc host should remain default ie 127.0.0.1
+    verify(mockRunnerBuilder).jsonRpcConfiguration(jsonRpcConfigArgumentCaptor.capture());
+    verify(mockRunnerBuilder).build();
+
+    assertThat(jsonRpcConfigArgumentCaptor.getValue().getHost()).isEqualTo("127.0.0.1");
   }
 
   @Test

ethereum/api/src/main/java/org/hyperledger/besu/ethereum/api/jsonrpc/JsonRpcConfiguration.java

@@ -32,7 +32,7 @@ import java.util.Optional;
 import com.google.common.base.MoreObjects;
 
 public class JsonRpcConfiguration {
-  private static final String DEFAULT_JSON_RPC_HOST = "127.0.0.1";
+  public static final String DEFAULT_JSON_RPC_HOST = "127.0.0.1";
   public static final int DEFAULT_JSON_RPC_PORT = 8545;
   public static final int DEFAULT_ENGINE_JSON_RPC_PORT = 8551;
   public static final int DEFAULT_MAX_ACTIVE_CONNECTIONS = 80;