From 1084d730920a940559d52a42d45de5fd776ae570 Mon Sep 17 00:00:00 2001
From: Philip O'Toole <philip@influxdb.com>
Date: Tue, 22 Sep 2015 10:04:29 -0700
Subject: [PATCH] Add cluster-service stats

---
 cluster/service.go | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/cluster/service.go b/cluster/service.go
index e74e7c30e74..5860aeb4cde 100644
--- a/cluster/service.go
+++ b/cluster/service.go
@@ -3,6 +3,7 @@ package cluster
 import (
 	"encoding/binary"
 	"encoding/json"
+	"expvar"
 	"fmt"
 	"io"
 	"log"
@@ -11,6 +12,7 @@ import (
 	"strings"
 	"sync"
 
+	"github.com/influxdb/influxdb"
 	"github.com/influxdb/influxdb/influxql"
 	"github.com/influxdb/influxdb/meta"
 	"github.com/influxdb/influxdb/models"
@@ -23,6 +25,15 @@ const MaxMessageSize = 1024 * 1024 * 1024 // 1GB
 // MuxHeader is the header byte used in the TCP mux.
 const MuxHeader = 2
 
+// Statistics maintained by the cluster package
+const (
+	writeShardReq       = "write_shard_req"
+	writeShardPointsReq = "write_shard_points_req"
+	writeShardFail      = "write_shard_fail"
+	mapShardReq         = "map_shard_req"
+	mapShardResp        = "map_shard_resp"
+)
+
 // Service processes data received over raw TCP connections.
 type Service struct {
 	mu sync.RWMutex
@@ -42,7 +53,8 @@ type Service struct {
 		CreateMapper(shardID uint64, stmt influxql.Statement, chunkSize int) (tsdb.Mapper, error)
 	}
 
-	Logger *log.Logger
+	Logger  *log.Logger
+	statMap *expvar.Map
 }
 
 // NewService returns a new instance of Service.
@@ -50,6 +62,7 @@ func NewService(c Config) *Service {
 	return &Service{
 		closing: make(chan struct{}),
 		Logger:  log.New(os.Stderr, "[tcp] ", log.LstdFlags),
+		statMap: influxdb.NewStatistics("cluster", "cluster", nil),
 	}
 }
 
@@ -145,12 +158,14 @@ func (s *Service) handleConn(conn net.Conn) {
 		// Delegate message processing by type.
 		switch typ {
 		case writeShardRequestMessage:
+			s.statMap.Add(writeShardReq, 1)
 			err := s.processWriteShardRequest(buf)
 			if err != nil {
 				s.Logger.Printf("process write shard error: %s", err)
 			}
 			s.writeShardResponse(conn, err)
 		case mapShardRequestMessage:
+			s.statMap.Add(mapShardReq, 1)
 			err := s.processMapShardRequest(conn, buf)
 			if err != nil {
 				s.Logger.Printf("process map shard error: %s", err)
@@ -171,6 +186,8 @@ func (s *Service) processWriteShardRequest(buf []byte) error {
 		return err
 	}
 
+	points := req.Points()
+	s.statMap.Add(writeShardPointsReq, int64(len(points)))
 	err := s.TSDBStore.WriteToShard(req.ShardID(), req.Points())
 
 	// We may have received a write for a shard that we don't have locally because the
@@ -198,6 +215,7 @@ func (s *Service) processWriteShardRequest(buf []byte) error {
 	}
 
 	if err != nil {
+		s.statMap.Add(writeShardFail, 1)
 		return fmt.Errorf("write shard %d: %s", req.ShardID(), err)
 	}
 
@@ -286,6 +304,7 @@ func (s *Service) processMapShardRequest(w io.Writer, buf []byte) error {
 		if err := writeMapShardResponseMessage(w, &resp); err != nil {
 			return err
 		}
+		s.statMap.Add(mapShardResp, 1)
 
 		if chunk == nil {
 			// All mapper data sent.