time_series_align.go

// Copyright 2019 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// Package snippets contains examples of using the monitoring API.
package snippets

// [START monitoring_read_timeseries_align]
import (
	"context"
	"fmt"
	"io"
	"time"

	monitoring "cloud.google.com/go/monitoring/apiv3"
	"github.com/golang/protobuf/ptypes/duration"
	"github.com/golang/protobuf/ptypes/timestamp"
	"google.golang.org/api/iterator"
	monitoringpb "google.golang.org/genproto/googleapis/monitoring/v3"
)

// readTimeSeriesAlign reads the last 20 minutes of the given metric and aligns
// everything on 10 minute intervals.
func readTimeSeriesAlign(w io.Writer, projectID string) error {
	ctx := context.Background()
	client, err := monitoring.NewMetricClient(ctx)
	if err != nil {
		return fmt.Errorf("NewMetricClient: %v", err)
	}
	startTime := time.Now().UTC().Add(time.Minute * -20)
	endTime := time.Now().UTC()
	req := &monitoringpb.ListTimeSeriesRequest{
		Name:   "projects/" + projectID,
		Filter: `metric.type="compute.googleapis.com/instance/cpu/utilization"`,
		Interval: &monitoringpb.TimeInterval{
			StartTime: &timestamp.Timestamp{
				Seconds: startTime.Unix(),
			},
			EndTime: &timestamp.Timestamp{
				Seconds: endTime.Unix(),
			},
		},
		Aggregation: &monitoringpb.Aggregation{
			PerSeriesAligner: monitoringpb.Aggregation_ALIGN_MEAN,
			AlignmentPeriod: &duration.Duration{
				Seconds: 600,
			},
		},
	}
	it := client.ListTimeSeries(ctx, req)
	for {
		resp, err := it.Next()
		if err == iterator.Done {
			break
		}
		if err != nil {
			return fmt.Errorf("could not read time series value: %v", err)
		}
		fmt.Fprintln(w, resp.GetMetric().GetLabels()["instance_name"])
		fmt.Fprintf(w, "\tNow: %.4f\n", resp.GetPoints()[0].GetValue().GetDoubleValue())
		if len(resp.GetPoints()) > 1 {
			fmt.Fprintf(w, "\t10 minutes ago: %.4f\n", resp.GetPoints()[1].GetValue().GetDoubleValue())
		}
	}
	fmt.Fprintln(w, "Done")
	return nil
}

// [END monitoring_read_timeseries_align]