add maxSeriesPoints for config.transfer.m3db (#609)

etc/transfer.yml

@@ -2,6 +2,7 @@ backend:
   datasource: "tsdb"
   m3db:
     enabled: false
+    maxSeriesPoints: 720                       # default 720
     name: "m3db"
     namespace: "default"
     seriesLimit: 0

src/modules/transfer/backend/m3db/convert.go

@@ -121,7 +121,7 @@ func xcludeResp(iter ident.TagIterator) *dataobj.XcludeResp {
 
 func resampleResp(data []*dataobj.TsdbQueryResponse, opts dataobj.QueryDataForUI) []*dataobj.TsdbQueryResponse {
 	for _, v := range data {
-		if len(v.Values) <= MAX_PONINTS {
+		if len(v.Values) <= maxSeriesPoints {
 			continue
 		}
 		v.Values = resample(v.Values, opts.Start, opts.End, int64(opts.Step), opts.ConsolFunc)

src/modules/transfer/backend/m3db/m3db.go

@@ -28,6 +28,10 @@ const (
 	MAX_PONINTS   = 720
 )
 
+var (
+	maxSeriesPoints = 720
+)
+
 type M3dbSection struct {
 	Name            string               `yaml:"name"`
 	Enabled         bool                 `yaml:"enabled"`
@@ -36,6 +40,7 @@ type M3dbSection struct {
 	SeriesLimit     int                  `yaml:"seriesLimit"`
 	DocsLimit       int                  `yaml:"docsLimit"`
 	MinStep         int                  `yaml:"minStep"`
+	MaxSeriesPoints int                  `yaml:"maxSeriesPoints"`
 	Config          client.Configuration `yaml:",inline"`
 	timeLimit       int64                `yaml:"-"`
 }
@@ -67,6 +72,10 @@ func NewClient(cfg M3dbSection) (*Client, error) {
 		cfg.MinStep = 1
 	}
 
+	if cfg.MaxSeriesPoints > 0 {
+		maxSeriesPoints = cfg.MaxSeriesPoints
+	}
+
 	cfg.timeLimit = int64(86400 * cfg.DaysLimit)
 
 	ret := &Client{
@@ -516,13 +525,13 @@ func (cfg M3dbSection) validateQueryDataForUI(in *dataobj.QueryDataForUI) (err e
 	}
 
 	if in.Step > 0 {
-		if n := (in.End - in.Start) / int64(in.Step); n > MAX_PONINTS {
+		if n := int(in.End-in.Start) / in.Step; n > maxSeriesPoints {
 			in.Step = 0
 		}
 	}
 
 	if in.Step <= 0 {
-		in.Step = int((in.End - in.Start) / MAX_PONINTS)
+		in.Step = int(in.End-in.Start) / maxSeriesPoints
 	}
 
 	if in.Step < cfg.MinStep {