RATIS-2068. Avoid logging raw StateMachine data body. (#1074)

ratis-grpc/src/main/java/org/apache/ratis/grpc/server/GrpcServerProtocolService.java

@@ -316,7 +316,7 @@ boolean isHeartbeat(AppendEntriesRequestProto request) {
 
       @Override
       String requestToString(AppendEntriesRequestProto request) {
-        return ServerStringUtils.toAppendEntriesRequestString(request);
+        return ServerStringUtils.toAppendEntriesRequestString(request, null);
       }
 
       @Override

ratis-server/src/main/java/org/apache/ratis/server/impl/RaftServerImpl.java

@@ -1471,7 +1471,8 @@ public CompletableFuture<AppendEntriesReplyProto> appendEntriesAsync(
 
       return appendEntriesAsync(leaderId, request.getCallId(), previous, requestRef);
     } catch(Exception t) {
-      LOG.error("{}: Failed appendEntries* {}", getMemberId(), toAppendEntriesRequestString(r), t);
+      LOG.error("{}: Failed appendEntries* {}", getMemberId(),
+          toAppendEntriesRequestString(r, stateMachine::toStateMachineLogEntryString), t);
       throw IOUtils.asIOException(t);
     } finally {
       requestRef.release();
@@ -1530,7 +1531,7 @@ private CompletableFuture<AppendEntriesReplyProto> appendEntriesAsync(RaftPeerId
     final List<LogEntryProto> entries = proto.getEntriesList();
     final boolean isHeartbeat = entries.isEmpty();
     logAppendEntries(isHeartbeat, () -> getMemberId() + ": appendEntries* "
-        + toAppendEntriesRequestString(proto));
+        + toAppendEntriesRequestString(proto, stateMachine::toStateMachineLogEntryString));
 
     final long leaderTerm = proto.getLeaderTerm();
     final long currentTerm;

ratis-server/src/main/java/org/apache/ratis/server/raftlog/LogProtoUtils.java

@@ -19,7 +19,6 @@
 
 import org.apache.ratis.proto.RaftProtos.*;
 import org.apache.ratis.protocol.ClientId;
-import org.apache.ratis.protocol.ClientInvocationId;
 import org.apache.ratis.protocol.RaftClientRequest;
 import org.apache.ratis.protocol.RaftPeer;
 import org.apache.ratis.server.RaftConfiguration;
@@ -46,9 +45,10 @@ public static String toLogEntryString(LogEntryProto entry, Function<StateMachine
     }
     final String s;
     if (entry.hasStateMachineLogEntry()) {
-      s = ", " + Optional.ofNullable(function)
-          .orElseGet(() -> proto -> "" + ClientInvocationId.valueOf(proto))
-          .apply(entry.getStateMachineLogEntry());
+      if (function == null) {
+        function = LogProtoUtils::stateMachineLogEntryProtoToString;
+      }
+      s = ", " + function.apply(entry.getStateMachineLogEntry());
     } else if (entry.hasMetadataEntry()) {
       final MetadataProto metadata = entry.getMetadataEntry();
       s = "(c:" + metadata.getCommitIndex() + ")";
@@ -70,7 +70,11 @@ static String peersToString(List<RaftPeerProto> peers) {
   }
 
   static String stateMachineLogEntryProtoToString(StateMachineLogEntryProto p) {
-    return "logData:" + p.getLogData() + ", stateMachineEntry:" + p.getType() + ":" + p.getStateMachineEntry();
+    final StateMachineEntryProto stateMachineEntry = p.getStateMachineEntry();
+    return p.getType()
+        + ": logData.size=" + p.getLogData().size()
+        + ", stateMachineData.size=" + stateMachineEntry.getStateMachineData().size()
+        + ", logEntryProtoSerializedSize=" + stateMachineEntry.getLogEntryProtoSerializedSize();
   }
 
   public static String toLogEntryString(LogEntryProto entry) {
@@ -82,10 +86,11 @@ public static String toLogEntriesString(List<LogEntryProto> entries) {
         : entries.stream().map(LogProtoUtils::toLogEntryString).collect(Collectors.toList()).toString();
   }
 
-  public static String toLogEntriesShortString(List<LogEntryProto> entries) {
+  public static String toLogEntriesShortString(List<LogEntryProto> entries,
+      Function<StateMachineLogEntryProto, String> stateMachineToString) {
     return entries == null ? null
         : entries.isEmpty()? "<empty>"
-        : "size=" + entries.size() + ", first=" + LogProtoUtils.toLogEntryString(entries.get(0));
+        : "size=" + entries.size() + ", first=" + toLogEntryString(entries.get(0), stateMachineToString);
   }
 
   public static LogEntryProto toLogEntryProto(RaftConfiguration conf, Long term, long index) {

ratis-server/src/main/java/org/apache/ratis/server/raftlog/RaftLogBase.java

@@ -199,10 +199,10 @@ private long appendImpl(long term, TransactionContext operation) throws StateMac
 
       appendEntry(operation.wrap(e), operation).whenComplete((returned, t) -> {
         if (t != null) {
-          LOG.error(name + ": Failed to write log entry " + LogProtoUtils.toLogEntryString(e), t);
+          LOG.error(name + ": Failed to write log entry " + toLogEntryString(e), t);
         } else if (returned != nextIndex) {
           LOG.error("{}: Indices mismatched: returned index={} but nextIndex={} for log entry {}",
-              name, returned, nextIndex, LogProtoUtils.toLogEntryString(e));
+              name, returned, nextIndex, toLogEntryString(e));
         } else {
           return; // no error
         }

ratis-server/src/main/java/org/apache/ratis/server/raftlog/segmented/SegmentedRaftLog.java

@@ -345,8 +345,7 @@ public ReferenceCountedObject<EntryWithData> retainEntryWithData(long index) thr
       }
       return future != null? newEntryWithData(entryRef, future): newEntryWithData(entryRef);
     } catch (Exception e) {
-      final String err = getName() + ": Failed readStateMachineData for " +
-          LogProtoUtils.toLogEntryString(entry);
+      final String err = getName() + ": Failed readStateMachineData for " + toLogEntryString(entry);
       LOG.error(err, e);
       throw new RaftLogIOException(err, JavaUtils.unwrapCompletionException(e));
     }
@@ -467,7 +466,7 @@ protected CompletableFuture<Long> appendEntryImpl(ReferenceCountedObject<LogEntr
       }
       return write.getFuture().whenComplete((clientReply, exception) -> appendEntryTimerContext.stop());
     } catch (Exception e) {
-      LOG.error("{}: Failed to append {}", getName(), LogProtoUtils.toLogEntryString(entry), e);
+      LOG.error("{}: Failed to append {}", getName(), toLogEntryString(entry), e);
       throw e;
     } finally {
       entryRef.release();
@@ -578,7 +577,8 @@ SegmentedRaftLogCache getRaftLogCache() {
 
   @Override
   public String toLogEntryString(LogEntryProto logEntry) {
-    return LogProtoUtils.toLogEntryString(logEntry, stateMachine::toStateMachineLogEntryString);
+    return LogProtoUtils.toLogEntryString(logEntry, stateMachine != null ?
+        stateMachine::toStateMachineLogEntryString : null);
   }
 
   public static Builder newBuilder() {

ratis-server/src/main/java/org/apache/ratis/server/util/ServerStringUtils.java

@@ -23,11 +23,13 @@
 import org.apache.ratis.proto.RaftProtos.InstallSnapshotRequestProto;
 import org.apache.ratis.proto.RaftProtos.LogEntryProto;
 import org.apache.ratis.proto.RaftProtos.RequestVoteReplyProto;
+import org.apache.ratis.proto.RaftProtos.StateMachineLogEntryProto;
 import org.apache.ratis.server.protocol.TermIndex;
 import org.apache.ratis.server.raftlog.LogProtoUtils;
 import org.apache.ratis.util.ProtoUtils;
 
 import java.util.List;
+import java.util.function.Function;
 
 /**
  *  This class provides convenient utilities for converting Protocol Buffers messages to strings.
@@ -41,7 +43,8 @@
 public final class ServerStringUtils {
   private ServerStringUtils() {}
 
-  public static String toAppendEntriesRequestString(AppendEntriesRequestProto request) {
+  public static String toAppendEntriesRequestString(AppendEntriesRequestProto request,
+      Function<StateMachineLogEntryProto, String> stateMachineToString) {
     if (request == null) {
       return null;
     }
@@ -51,7 +54,8 @@ public static String toAppendEntriesRequestString(AppendEntriesRequestProto requ
         + ",previous=" + TermIndex.valueOf(request.getPreviousLog())
         + ",leaderCommit=" + request.getLeaderCommit()
         + ",initializing? " + request.getInitializing()
-        + "," + (entries.isEmpty()? "HEARTBEAT" : "entries: " + LogProtoUtils.toLogEntriesShortString(entries));
+        + "," + (entries.isEmpty()? "HEARTBEAT" : "entries: " +
+        LogProtoUtils.toLogEntriesShortString(entries, stateMachineToString));
   }
 
   public static String toAppendEntriesReplyString(AppendEntriesReplyProto reply) {