Start a new api package

internal/types/types.go

@@ -1,8 +1,58 @@
 package types
 
+import (
+	"encoding/json"
+	"fmt"
+)
+
 type Stats struct {
 	Samples int   `json:"samples"`
 	Min     Float `json:"min"`
 	Avg     Float `json:"avg"`
 	Max     Float `json:"max"`
 }
+
+type MetricConfig struct {
+	// Interval in seconds at which measurements will arive.
+	Frequency int64 `json:"frequency"`
+
+	// Can be 'sum', 'avg' or null. Describes how to aggregate metrics from the same timestep over the hierarchy.
+	Aggregation AggregationStrategy `json:"aggregation"`
+
+	// Private, used internally...
+	Offset int
+}
+
+type Metric struct {
+	Name  string
+	Value Float
+	Conf  MetricConfig
+}
+
+// For aggregation over multiple values at different cpus/sockets/..., not time!
+type AggregationStrategy int
+
+const (
+	NoAggregation AggregationStrategy = iota
+	SumAggregation
+	AvgAggregation
+)
+
+func (as *AggregationStrategy) UnmarshalJSON(data []byte) error {
+	var str string
+	if err := json.Unmarshal(data, &str); err != nil {
+		return err
+	}
+
+	switch str {
+	case "":
+		*as = NoAggregation
+	case "sum":
+		*as = SumAggregation
+	case "avg":
+		*as = AvgAggregation
+	default:
+		return fmt.Errorf("invalid aggregation strategy: %#v", str)
+	}
+	return nil
+}