SERVER-9003 - Display replica set chaining topology in rs.status()

Include syncingTo in heartbeat response and display this info for each
replica set member in the replSetGetStatus command.

3 files changed, 15 insertions, 0 deletions

diff --git a/src/mongo/db/repl/health.cpp b/src/mongo/db/repl/health.cpp
index 7c2f85f6c87..a45809df732 100644
--- a/src/mongo/db/repl/health.cpp
+++ b/src/mongo/db/repl/health.cpp
@@ -446,6 +446,11 @@ namespace mongo {
                 bb.append("authenticated", false);
             }
 
+            string syncingTo = m->hbinfo().syncingTo;
+            if (!syncingTo.empty()) {
+                bb.append("syncingTo", syncingTo);
+            }
+
             v.push_back(bb.obj());
             m = m->next();
         }
diff --git a/src/mongo/db/repl/heartbeat.cpp b/src/mongo/db/repl/heartbeat.cpp
index fbac43b1d99..5ba3d5f3427 100644
--- a/src/mongo/db/repl/heartbeat.cpp
+++ b/src/mongo/db/repl/heartbeat.cpp
@@ -122,6 +122,11 @@ namespace mongo {
             result.append("hbmsg", theReplSet->hbmsg());
             result.append("time", (long long) time(0));
             result.appendDate("opTime", theReplSet->lastOpTimeWritten.asDate());
+            const Member *syncTarget = replset::BackgroundSync::get()->getSyncTarget();
+            if (syncTarget) {
+                result.append("syncingTo", syncTarget->fullName());
+            }
+
             int v = theReplSet->config().version;
             result.append("v", v);
             if( v > cmdObj["v"].Int() )
@@ -396,6 +401,10 @@ namespace mongo {
             }
             mem.health = 1.0;
             mem.lastHeartbeatMsg = info["hbmsg"].String();
+            if (info.hasElement("syncingTo")) {
+                mem.syncingTo = info["syncingTo"].String();
+            }
+
             if( info.hasElement("opTime") )
                 mem.opTime = info["opTime"].Date();
 
diff --git a/src/mongo/db/repl/rs_member.h b/src/mongo/db/repl/rs_member.h
index 967052c4da8..100a2013314 100644
--- a/src/mongo/db/repl/rs_member.h
+++ b/src/mongo/db/repl/rs_member.h
@@ -84,6 +84,7 @@ namespace mongo {
         // This is the last time we got a heartbeat request from a given member.
         time_t lastHeartbeatRecv;
         DiagStr lastHeartbeatMsg;
+        DiagStr syncingTo;
         OpTime opTime;
         int skew;
         bool authIssue;