1// Copyright 2017 The Prometheus Authors 2// Licensed under the Apache License, Version 2.0 (the "License"); 3// you may not use this file except in compliance with the License. 4// You may obtain a copy of the License at 5// 6// http://www.apache.org/licenses/LICENSE-2.0 7// 8// Unless required by applicable law or agreed to in writing, software 9// distributed under the License is distributed on an "AS IS" BASIS, 10// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 11// See the License for the specific language governing permissions and 12// limitations under the License. 13 14package triton 15 16import ( 17 "encoding/json" 18 "fmt" 19 "io/ioutil" 20 "net/http" 21 "time" 22 23 "github.com/prometheus/client_golang/prometheus" 24 "github.com/prometheus/common/log" 25 "github.com/prometheus/common/model" 26 "github.com/prometheus/prometheus/config" 27 "github.com/prometheus/prometheus/util/httputil" 28 "golang.org/x/net/context" 29) 30 31const ( 32 tritonLabel = model.MetaLabelPrefix + "triton_" 33 tritonLabelMachineId = tritonLabel + "machine_id" 34 tritonLabelMachineAlias = tritonLabel + "machine_alias" 35 tritonLabelMachineBrand = tritonLabel + "machine_brand" 36 tritonLabelMachineImage = tritonLabel + "machine_image" 37 tritonLabelServerId = tritonLabel + "server_id" 38 namespace = "prometheus" 39) 40 41var ( 42 refreshFailuresCount = prometheus.NewCounter( 43 prometheus.CounterOpts{ 44 Name: "prometheus_sd_triton_refresh_failures_total", 45 Help: "The number of Triton-SD scrape failures.", 46 }) 47 refreshDuration = prometheus.NewSummary( 48 prometheus.SummaryOpts{ 49 Name: "prometheus_sd_triton_refresh_duration_seconds", 50 Help: "The duration of a Triton-SD refresh in seconds.", 51 }) 52) 53 54func init() { 55 prometheus.MustRegister(refreshFailuresCount) 56 prometheus.MustRegister(refreshDuration) 57} 58 59type DiscoveryResponse struct { 60 Containers []struct { 61 ServerUUID string `json:"server_uuid"` 62 VMAlias string `json:"vm_alias"` 63 VMBrand string `json:"vm_brand"` 64 VMImageUUID string `json:"vm_image_uuid"` 65 VMUUID string `json:"vm_uuid"` 66 } `json:"containers"` 67} 68 69// Discovery periodically performs Triton-SD requests. It implements 70// the TargetProvider interface. 71type Discovery struct { 72 client *http.Client 73 interval time.Duration 74 logger log.Logger 75 sdConfig *config.TritonSDConfig 76} 77 78// New returns a new Discovery which periodically refreshes its targets. 79func New(logger log.Logger, conf *config.TritonSDConfig) (*Discovery, error) { 80 tls, err := httputil.NewTLSConfig(conf.TLSConfig) 81 if err != nil { 82 return nil, err 83 } 84 85 transport := &http.Transport{TLSClientConfig: tls} 86 client := &http.Client{Transport: transport} 87 88 return &Discovery{ 89 client: client, 90 interval: time.Duration(conf.RefreshInterval), 91 logger: logger, 92 sdConfig: conf, 93 }, nil 94} 95 96// Run implements the TargetProvider interface. 97func (d *Discovery) Run(ctx context.Context, ch chan<- []*config.TargetGroup) { 98 defer close(ch) 99 100 ticker := time.NewTicker(d.interval) 101 defer ticker.Stop() 102 103 // Get an initial set right away. 104 tg, err := d.refresh() 105 if err != nil { 106 d.logger.With("err", err).Error("Refreshing targets failed") 107 } else { 108 ch <- []*config.TargetGroup{tg} 109 } 110 111 for { 112 select { 113 case <-ticker.C: 114 tg, err := d.refresh() 115 if err != nil { 116 d.logger.With("err", err).Error("Refreshing targets failed") 117 } else { 118 ch <- []*config.TargetGroup{tg} 119 } 120 case <-ctx.Done(): 121 return 122 } 123 } 124} 125 126func (d *Discovery) refresh() (tg *config.TargetGroup, err error) { 127 t0 := time.Now() 128 defer func() { 129 refreshDuration.Observe(time.Since(t0).Seconds()) 130 if err != nil { 131 refreshFailuresCount.Inc() 132 } 133 }() 134 135 var endpoint = fmt.Sprintf("https://%s:%d/v%d/discover", d.sdConfig.Endpoint, d.sdConfig.Port, d.sdConfig.Version) 136 tg = &config.TargetGroup{ 137 Source: endpoint, 138 } 139 140 resp, err := d.client.Get(endpoint) 141 if err != nil { 142 return tg, fmt.Errorf("an error occurred when requesting targets from the discovery endpoint. %s", err) 143 } 144 145 defer resp.Body.Close() 146 147 data, err := ioutil.ReadAll(resp.Body) 148 if err != nil { 149 return tg, fmt.Errorf("an error occurred when reading the response body. %s", err) 150 } 151 152 dr := DiscoveryResponse{} 153 err = json.Unmarshal(data, &dr) 154 if err != nil { 155 return tg, fmt.Errorf("an error occurred unmarshaling the disovery response json. %s", err) 156 } 157 158 for _, container := range dr.Containers { 159 labels := model.LabelSet{ 160 tritonLabelMachineId: model.LabelValue(container.VMUUID), 161 tritonLabelMachineAlias: model.LabelValue(container.VMAlias), 162 tritonLabelMachineBrand: model.LabelValue(container.VMBrand), 163 tritonLabelMachineImage: model.LabelValue(container.VMImageUUID), 164 tritonLabelServerId: model.LabelValue(container.ServerUUID), 165 } 166 addr := fmt.Sprintf("%s.%s:%d", container.VMUUID, d.sdConfig.DNSSuffix, d.sdConfig.Port) 167 labels[model.AddressLabel] = model.LabelValue(addr) 168 tg.Targets = append(tg.Targets, labels) 169 } 170 171 return tg, nil 172} 173