Use type with custom MarshalJSON for metrics

This commit is contained in:
Lou Knauer 2021-08-24 10:39:16 +02:00
parent f7310bc70a
commit 8d827e44b4
2 changed files with 21 additions and 5 deletions

7
api.go
View File

@ -8,13 +8,14 @@ import (
"strconv"
"time"
"github.com/ClusterCockpit/cc-metric-store/lineprotocol"
"github.com/gorilla/mux"
)
type HostData struct {
Host string `json:"host"`
Start int64 `json:"start"`
Data []float64 `json:"data"`
Host string `json:"host"`
Start int64 `json:"start"`
Data []lineprotocol.Float `json:"data"`
}
type MetricData struct {

View File

@ -2,14 +2,29 @@ package lineprotocol
import (
"errors"
"math"
"strconv"
"strings"
"time"
)
// Go's JSON encoder for floats does not support NaN (https://github.com/golang/go/issues/3480).
// This program uses NaN as a signal for missing data.
// For the HTTP JSON API to be able to handle NaN values,
// we have to use our own type which implements encoding/json.Marshaler itself.
type Float float64
func (f Float) MarshalJSON() ([]byte, error) {
if math.IsNaN(float64(f)) {
return []byte("null"), nil
}
return []byte(strconv.FormatFloat(float64(f), 'f', -1, 64)), nil
}
type Metric struct {
Name string
Value float64
Value Float
}
// measurement: node or cpu
@ -59,7 +74,7 @@ func Parse(rawline string) (*Line, error) {
line.Fields = append(line.Fields, Metric{
Name: pair[0],
Value: field,
Value: Float(field),
})
}