Implement groupBy

pkg/datasource/functions.go

@@ -2,8 +2,8 @@ package datasource
 
 import (
 	"fmt"
-	"time"
 
+	"github.com/alexanderzobnin/grafana-zabbix/pkg/gtime"
 	"github.com/alexanderzobnin/grafana-zabbix/pkg/timeseries"
 )
 
@@ -11,20 +11,26 @@ var errFunctionNotSupported = func(name string) error {
 	return fmt.Errorf("function not supported: %s", name)
 }
 
-type DataProcessingFunc = func(series timeseries.TimeSeries, params ...string) timeseries.TimeSeries
+type DataProcessingFunc = func(series timeseries.TimeSeries, params ...string) (timeseries.TimeSeries, error)
 
 var funcMap map[string]DataProcessingFunc
 
 func init() {
-	funcMap = make(map[string]DataProcessingFunc)
-	funcMap["groupBy"] = applyGroupBy
+	funcMap = map[string]DataProcessingFunc{
+		"groupBy": applyGroupBy,
+	}
+
 }
 
 func applyFunctions(series []*timeseries.TimeSeriesData, functions []QueryFunction) ([]*timeseries.TimeSeriesData, error) {
 	for _, f := range functions {
 		if applyFunc, ok := funcMap[f.Def.Name]; ok {
 			for _, s := range series {
-				s.TS = applyFunc(s.TS, f.Params...)
+				result, err := applyFunc(s.TS, f.Params...)
+				if err != nil {
+					return nil, err
+				}
+				s.TS = result
 			}
 		} else {
 			err := errFunctionNotSupported(f.Def.Name)
@@ -34,7 +40,32 @@ func applyFunctions(series []*timeseries.TimeSeriesData, functions []QueryFuncti
 	return series, nil
 }
 
-func applyGroupBy(series timeseries.TimeSeries, params ...string) timeseries.TimeSeries {
-	s := series.GroupBy(time.Minute, "avg")
-	return s
+func applyGroupBy(series timeseries.TimeSeries, params ...string) (timeseries.TimeSeries, error) {
+	pInterval := params[0]
+	pAgg := params[1]
+	interval, err := gtime.ParseInterval(pInterval)
+	if err != nil {
+		return nil, err
+	}
+
+	aggFunc := getAggFunc(pAgg)
+	s := series.GroupBy(interval, aggFunc)
+	return s, nil
+}
+
+func getAggFunc(agg string) timeseries.AggFunc {
+	switch agg {
+	case "avg":
+		return timeseries.AggAvg
+	case "max":
+		return timeseries.AggMax
+	case "min":
+		return timeseries.AggMin
+	case "first":
+		return timeseries.AggFirst
+	case "last":
+		return timeseries.AggLast
+	default:
+		return timeseries.AggAvg
+	}
 }