Convert GetMetricData results to Mackerel metric format.

main.go

package main

import (
	"encoding/json"
	"fmt"
	"os"
	"time"

	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/cloudwatch"
)

func main() {
	var qs []*cloudwatch.MetricDataQuery
	if err := json.NewDecoder(os.Stdin).Decode(&qs); err != nil {
		panic(err)
	}

	svc := cloudwatch.New(session.Must(session.NewSession(&aws.Config{})))
	now := time.Now()

	res, err := svc.GetMetricData(&cloudwatch.GetMetricDataInput{
		StartTime:         aws.Time(now.Add(-4 * time.Minute)),
		EndTime:           aws.Time(now),
		MetricDataQueries: qs,
	})
	if err != nil {
		panic(err)
	}
	for _, r := range res.MetricDataResults {
		for i, ts := range r.Timestamps {
			fmt.Printf("%s\t%d\t%f\n", *r.Label, (*ts).Unix(), *(r.Values[i]))
		}
	}
}