prometheus/discovery/gce/gce.go
Julius Volz 099df0c5f0 Migrate "golang.org/x/net/context" -> "context" (#3333)
In some places, where ctxhttp or gRPC are concerned, we still need to use the
old contexts.
2017-10-24 21:21:42 -07:00

213 lines
6.2 KiB
Go

// Copyright 2015 The Prometheus Authors
// 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
//
// http://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 gce
import (
"context"
"fmt"
"net/http"
"strings"
"time"
"github.com/go-kit/kit/log"
"github.com/go-kit/kit/log/level"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/common/model"
"golang.org/x/oauth2"
"golang.org/x/oauth2/google"
"google.golang.org/api/compute/v1"
"github.com/prometheus/prometheus/config"
"github.com/prometheus/prometheus/util/strutil"
)
const (
gceLabel = model.MetaLabelPrefix + "gce_"
gceLabelProject = gceLabel + "project"
gceLabelZone = gceLabel + "zone"
gceLabelNetwork = gceLabel + "network"
gceLabelSubnetwork = gceLabel + "subnetwork"
gceLabelPublicIP = gceLabel + "public_ip"
gceLabelPrivateIP = gceLabel + "private_ip"
gceLabelInstanceName = gceLabel + "instance_name"
gceLabelInstanceStatus = gceLabel + "instance_status"
gceLabelTags = gceLabel + "tags"
gceLabelMetadata = gceLabel + "metadata_"
)
var (
gceSDRefreshFailuresCount = prometheus.NewCounter(
prometheus.CounterOpts{
Name: "prometheus_sd_gce_refresh_failures_total",
Help: "The number of GCE-SD refresh failures.",
})
gceSDRefreshDuration = prometheus.NewSummary(
prometheus.SummaryOpts{
Name: "prometheus_sd_gce_refresh_duration",
Help: "The duration of a GCE-SD refresh in seconds.",
})
)
func init() {
prometheus.MustRegister(gceSDRefreshFailuresCount)
prometheus.MustRegister(gceSDRefreshDuration)
}
// Discovery periodically performs GCE-SD requests. It implements
// the TargetProvider interface.
type Discovery struct {
project string
zone string
filter string
client *http.Client
svc *compute.Service
isvc *compute.InstancesService
interval time.Duration
port int
tagSeparator string
logger log.Logger
}
// NewDiscovery returns a new Discovery which periodically refreshes its targets.
func NewDiscovery(conf *config.GCESDConfig, logger log.Logger) (*Discovery, error) {
if logger == nil {
logger = log.NewNopLogger()
}
gd := &Discovery{
project: conf.Project,
zone: conf.Zone,
filter: conf.Filter,
interval: time.Duration(conf.RefreshInterval),
port: conf.Port,
tagSeparator: conf.TagSeparator,
logger: logger,
}
var err error
gd.client, err = google.DefaultClient(oauth2.NoContext, compute.ComputeReadonlyScope)
if err != nil {
return nil, fmt.Errorf("error setting up communication with GCE service: %s", err)
}
gd.svc, err = compute.New(gd.client)
if err != nil {
return nil, fmt.Errorf("error setting up communication with GCE service: %s", err)
}
gd.isvc = compute.NewInstancesService(gd.svc)
return gd, nil
}
// Run implements the TargetProvider interface.
func (d *Discovery) Run(ctx context.Context, ch chan<- []*config.TargetGroup) {
// Get an initial set right away.
tg, err := d.refresh()
if err != nil {
level.Error(d.logger).Log("msg", "Refresh failed", "err", err)
} else {
select {
case ch <- []*config.TargetGroup{tg}:
case <-ctx.Done():
}
}
ticker := time.NewTicker(d.interval)
defer ticker.Stop()
for {
select {
case <-ticker.C:
tg, err := d.refresh()
if err != nil {
level.Error(d.logger).Log("msg", "Refresh failed", "err", err)
continue
}
select {
case ch <- []*config.TargetGroup{tg}:
case <-ctx.Done():
}
case <-ctx.Done():
return
}
}
}
func (d *Discovery) refresh() (tg *config.TargetGroup, err error) {
t0 := time.Now()
defer func() {
gceSDRefreshDuration.Observe(time.Since(t0).Seconds())
if err != nil {
gceSDRefreshFailuresCount.Inc()
}
}()
tg = &config.TargetGroup{
Source: fmt.Sprintf("GCE_%s_%s", d.project, d.zone),
}
ilc := d.isvc.List(d.project, d.zone)
if len(d.filter) > 0 {
ilc = ilc.Filter(d.filter)
}
err = ilc.Pages(nil, func(l *compute.InstanceList) error {
for _, inst := range l.Items {
if len(inst.NetworkInterfaces) == 0 {
continue
}
labels := model.LabelSet{
gceLabelProject: model.LabelValue(d.project),
gceLabelZone: model.LabelValue(inst.Zone),
gceLabelInstanceName: model.LabelValue(inst.Name),
gceLabelInstanceStatus: model.LabelValue(inst.Status),
}
priIface := inst.NetworkInterfaces[0]
labels[gceLabelNetwork] = model.LabelValue(priIface.Network)
labels[gceLabelSubnetwork] = model.LabelValue(priIface.Subnetwork)
labels[gceLabelPrivateIP] = model.LabelValue(priIface.NetworkIP)
addr := fmt.Sprintf("%s:%d", priIface.NetworkIP, d.port)
labels[model.AddressLabel] = model.LabelValue(addr)
// Tags in GCE are usually only used for networking rules.
if inst.Tags != nil && len(inst.Tags.Items) > 0 {
// We surround the separated list with the separator as well. This way regular expressions
// in relabeling rules don't have to consider tag positions.
tags := d.tagSeparator + strings.Join(inst.Tags.Items, d.tagSeparator) + d.tagSeparator
labels[gceLabelTags] = model.LabelValue(tags)
}
// GCE metadata are key-value pairs for user supplied attributes.
if inst.Metadata != nil {
for _, i := range inst.Metadata.Items {
// Protect against occasional nil pointers.
if i.Value == nil {
continue
}
name := strutil.SanitizeLabelName(i.Key)
labels[gceLabelMetadata+model.LabelName(name)] = model.LabelValue(*i.Value)
}
}
if len(priIface.AccessConfigs) > 0 {
ac := priIface.AccessConfigs[0]
if ac.Type == "ONE_TO_ONE_NAT" {
labels[gceLabelPublicIP] = model.LabelValue(ac.NatIP)
}
}
tg.Targets = append(tg.Targets, labels)
}
return nil
})
if err != nil {
return tg, fmt.Errorf("error retrieving refresh targets from gce: %s", err)
}
return tg, nil
}