RLock shard during diagnostics

CHANGELOG.md

@@ -17,7 +17,7 @@
 - [#2300](https://github.com/influxdb/influxdb/pull/2300): Refactor integration tests.  Properly close Graphite/OpenTSDB listeners.
 - [#2338](https://github.com/influxdb/influxdb/pull/2338): Fix panic if tag key isn't double quoted when it should have been
 - [#2340](https://github.com/influxdb/influxdb/pull/2340): Fix SHOW DIAGNOSTICS panic if any shard was non-local.
-
+- [#2351](https://github.com/influxdb/influxdb/pull/2351): Fix data race by rlocking shard during diagnostics.
 
 ## v0.9.0-rc25 [2015-04-15]
 

server.go

@@ -3302,7 +3302,7 @@ func (s *Server) DiagnosticsAsRows() []*influxql.Row {
 		for _, n := range sh.DataNodeIDs {
 			nodes = append(nodes, strconv.FormatUint(n, 10))
 			shardsRow.Values = append(shardsRow.Values, []interface{}{now, strconv.FormatUint(sh.ID, 10),
-				strings.Join(nodes, ","), strconv.FormatUint(sh.index, 10)})
+				strings.Join(nodes, ","), strconv.FormatUint(sh.Index(), 10)})
 		}
 		// Shard may not be local to this node.
 		if sh.store != nil {

shard.go

@@ -133,6 +133,14 @@ func shardMetaIndex(tx *bolt.Tx) uint64 {
 	return index
 }
 
+// Index returns the highest Raft index processed by this shard. Shard RLock
+// held during execution.
+func (s *Shard) Index() uint64 {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return s.index
+}
+
 // close shuts down the shard's store.
 func (s *Shard) close() error {
 	// Wait for goroutines to stop.