adds digital ocean sd (#1376)

* adds digital ocean sd config

* adds digital ocean sd
https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1367

* typo fix

app/vmagent/README.md

@@ -177,6 +177,8 @@ The following scrape types in [scrape_config](https://prometheus.io/docs/prometh
   See [dockerswarm_sd_config](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#dockerswarm_sd_config) for details.
 * `eureka_sd_configs` - is for scraping targets registered in [Netflix Eureka](https://github.com/Netflix/eureka).
   See [eureka_sd_config](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#eureka_sd_config) for details.
+* `digitalocean_sd_configs` is for scraping targerts registered in [DigitalOcean](https://www.digitalocean.com/)
+  See [digitalocean_sd_config](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#digitalocean_sd_config) for details.
 
 Please file feature requests to [our issue tracker](https://github.com/VictoriaMetrics/VictoriaMetrics/issues) if you need other service discovery mechanisms to be supported by `vmagent`.
 
@@ -627,6 +629,8 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
     	Wait time used by Consul service discovery. Default value is used if not set
   -promscrape.consulSDCheckInterval duration
     	Interval for checking for changes in Consul. This works only if consul_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#consul_sd_config for details (default 30s)
+  -promscrape.digitaloceanSDCheckInterval duration
+        Interval for checking for changes in digital ocean. This works only if digitalocean_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#digitalocean_sd_config for details (default 1m0s)    	
   -promscrape.disableCompression
     	Whether to disable sending 'Accept-Encoding: gzip' request headers to all the scrape targets. This may reduce CPU usage on scrape targets at the cost of higher network bandwidth utilization. It is possible to set 'disable_compression: true' individually per each 'scrape_config' section in '-promscrape.config' for fine grained control
   -promscrape.disableKeepAlive

docs/vmagent.md

@@ -181,6 +181,8 @@ The following scrape types in [scrape_config](https://prometheus.io/docs/prometh
   See [dockerswarm_sd_config](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#dockerswarm_sd_config) for details.
 * `eureka_sd_configs` - is for scraping targets registered in [Netflix Eureka](https://github.com/Netflix/eureka).
   See [eureka_sd_config](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#eureka_sd_config) for details.
+* `digitalocean_sd_configs` is for scraping targerts registered in [DigitalOcean](https://www.digitalocean.com/)
+  See [digitalocean_sd_config](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#digitalocean_sd_config) for details.
 
 Please file feature requests to [our issue tracker](https://github.com/VictoriaMetrics/VictoriaMetrics/issues) if you need other service discovery mechanisms to be supported by `vmagent`.
 
@@ -631,6 +633,8 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
     	Wait time used by Consul service discovery. Default value is used if not set
   -promscrape.consulSDCheckInterval duration
     	Interval for checking for changes in Consul. This works only if consul_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#consul_sd_config for details (default 30s)
+  -promscrape.digitaloceanSDCheckInterval duration
+        Interval for checking for changes in digital ocean. This works only if digitalocean_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#digitalocean_sd_config for details (default 1m0s)    	
   -promscrape.disableCompression
     	Whether to disable sending 'Accept-Encoding: gzip' request headers to all the scrape targets. This may reduce CPU usage on scrape targets at the cost of higher network bandwidth utilization. It is possible to set 'disable_compression: true' individually per each 'scrape_config' section in '-promscrape.config' for fine grained control
   -promscrape.disableKeepAlive

lib/promscrape/config.go

@@ -19,6 +19,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promrelabel"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape/discovery/consul"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape/discovery/digitalocean"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape/discovery/dns"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape/discovery/dockerswarm"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape/discovery/ec2"
@@ -106,16 +107,17 @@ type ScrapeConfig struct {
 	MetricRelabelConfigs []promrelabel.RelabelConfig `yaml:"metric_relabel_configs,omitempty"`
 	SampleLimit          int                         `yaml:"sample_limit,omitempty"`
 
-	StaticConfigs        []StaticConfig         `yaml:"static_configs,omitempty"`
-	FileSDConfigs        []FileSDConfig         `yaml:"file_sd_configs,omitempty"`
-	KubernetesSDConfigs  []kubernetes.SDConfig  `yaml:"kubernetes_sd_configs,omitempty"`
-	OpenStackSDConfigs   []openstack.SDConfig   `yaml:"openstack_sd_configs,omitempty"`
-	ConsulSDConfigs      []consul.SDConfig      `yaml:"consul_sd_configs,omitempty"`
-	EurekaSDConfigs      []eureka.SDConfig      `yaml:"eureka_sd_configs,omitempty"`
-	DockerSwarmSDConfigs []dockerswarm.SDConfig `yaml:"dockerswarm_sd_configs,omitempty"`
-	DNSSDConfigs         []dns.SDConfig         `yaml:"dns_sd_configs,omitempty"`
-	EC2SDConfigs         []ec2.SDConfig         `yaml:"ec2_sd_configs,omitempty"`
-	GCESDConfigs         []gce.SDConfig         `yaml:"gce_sd_configs,omitempty"`
+	StaticConfigs         []StaticConfig          `yaml:"static_configs,omitempty"`
+	FileSDConfigs         []FileSDConfig          `yaml:"file_sd_configs,omitempty"`
+	KubernetesSDConfigs   []kubernetes.SDConfig   `yaml:"kubernetes_sd_configs,omitempty"`
+	OpenStackSDConfigs    []openstack.SDConfig    `yaml:"openstack_sd_configs,omitempty"`
+	ConsulSDConfigs       []consul.SDConfig       `yaml:"consul_sd_configs,omitempty"`
+	EurekaSDConfigs       []eureka.SDConfig       `yaml:"eureka_sd_configs,omitempty"`
+	DockerSwarmSDConfigs  []dockerswarm.SDConfig  `yaml:"dockerswarm_sd_configs,omitempty"`
+	DNSSDConfigs          []dns.SDConfig          `yaml:"dns_sd_configs,omitempty"`
+	EC2SDConfigs          []ec2.SDConfig          `yaml:"ec2_sd_configs,omitempty"`
+	GCESDConfigs          []gce.SDConfig          `yaml:"gce_sd_configs,omitempty"`
+	DigitaloceanSDConfigs []digitalocean.SDConfig `yaml:"digitalocean_sd_configs,omitempty"`
 
 	// These options are supported only by lib/promscrape.
 	RelabelDebug        bool                       `yaml:"relabel_debug,omitempty"`
@@ -488,6 +490,34 @@ func (cfg *Config) getGCESDScrapeWork(prev []*ScrapeWork) []*ScrapeWork {
 	return dst
 }
 
+// getDigitalOceanDScrapeWork returns `digitalocean_sd_configs` ScrapeWork from cfg.
+func (cfg *Config) getDigitalOceanDScrapeWork(prev []*ScrapeWork) []*ScrapeWork {
+	swsPrevByJob := getSWSByJob(prev)
+	dst := make([]*ScrapeWork, 0, len(prev))
+	for i := range cfg.ScrapeConfigs {
+		sc := &cfg.ScrapeConfigs[i]
+		dstLen := len(dst)
+		ok := true
+		for j := range sc.DigitaloceanSDConfigs {
+			sdc := &sc.DigitaloceanSDConfigs[j]
+			var okLocal bool
+			dst, okLocal = appendSDScrapeWork(dst, sdc, cfg.baseDir, sc.swc, "digitalocean_sd_config")
+			if ok {
+				ok = okLocal
+			}
+		}
+		if ok {
+			continue
+		}
+		swsPrev := swsPrevByJob[sc.swc.jobName]
+		if len(swsPrev) > 0 {
+			logger.Errorf("there were errors when discovering digitalocean targets for job %q, so preserving the previous targets", sc.swc.jobName)
+			dst = append(dst[:dstLen], swsPrev...)
+		}
+	}
+	return dst
+}
+
 // getFileSDScrapeWork returns `file_sd_configs` ScrapeWork from cfg.
 func (cfg *Config) getFileSDScrapeWork(prev []*ScrapeWork) []*ScrapeWork {
 	// Create a map for the previous scrape work.

lib/promscrape/discovery/digitalocean/api.go

@@ -0,0 +1,92 @@
+package digitalocean
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape/discoveryutils"
+)
+
+var configMap = discoveryutils.NewConfigMap()
+
+type apiConfig struct {
+	client *discoveryutils.Client
+	port   int
+}
+
+func newAPIConfig(sdc *SDConfig, baseDir string) (*apiConfig, error) {
+	ac, err := sdc.HTTPClientConfig.NewConfig(baseDir)
+	if err != nil {
+		return nil, fmt.Errorf("cannot parse auth config: %w", err)
+	}
+
+	apiServer := sdc.Server
+	if apiServer == "" {
+		apiServer = "https://api.digitalocean.com"
+	}
+	if !strings.Contains(apiServer, "://") {
+		scheme := "http"
+		if sdc.HTTPClientConfig.TLSConfig != nil {
+			scheme = "https"
+		}
+		apiServer = scheme + "://" + apiServer
+	}
+	proxyAC, err := sdc.ProxyClientConfig.NewConfig(baseDir)
+	if err != nil {
+		return nil, fmt.Errorf("cannot parse proxy auth config: %w", err)
+	}
+	client, err := discoveryutils.NewClient(apiServer, ac, sdc.ProxyURL, proxyAC)
+	if err != nil {
+		return nil, fmt.Errorf("cannot create HTTP client for %q: %w", apiServer, err)
+	}
+	cfg := &apiConfig{
+		client: client,
+		port:   sdc.Port,
+	}
+	if cfg.port == 0 {
+		cfg.port = 80
+	}
+	return cfg, nil
+}
+
+func getAPIConfig(sdc *SDConfig, baseDir string) (*apiConfig, error) {
+	v, err := configMap.Get(sdc, func() (interface{}, error) { return newAPIConfig(sdc, baseDir) })
+	if err != nil {
+		return nil, err
+	}
+	return v.(*apiConfig), nil
+
+}
+
+const dropletsAPIPath = "/v2/droplets"
+
+func getDroplets(getAPIResponse func(string) ([]byte, error)) ([]droplet, error) {
+	var droplets []droplet
+
+	nextAPIURL := dropletsAPIPath
+	for nextAPIURL != "" {
+		data, err := getAPIResponse(nextAPIURL)
+		if err != nil {
+			return nil, fmt.Errorf("cannot fetch data from digitalocean list api: %w", err)
+		}
+		apiResp, err := parseAPIResponse(data)
+		if err != nil {
+			return nil, err
+		}
+		droplets = append(droplets, apiResp.Droplets...)
+		nextAPIURL, err = apiResp.nextURLPath()
+		if err != nil {
+			return nil, err
+		}
+	}
+	return droplets, nil
+}
+
+func parseAPIResponse(data []byte) (*listDropletResponse, error) {
+	var dps listDropletResponse
+	if err := json.Unmarshal(data, &dps); err != nil {
+		return nil, fmt.Errorf("failed parse digitalocean api response: %q, err: %w", data, err)
+	}
+	return &dps, nil
+}

lib/promscrape/discovery/digitalocean/api_test.go

@@ -0,0 +1,349 @@
+package digitalocean
+
+import (
+	"reflect"
+	"testing"
+)
+
+func Test_parseAPIResponse(t *testing.T) {
+	type args struct {
+		data []byte
+	}
+	tests := []struct {
+		name    string
+		args    args
+		want    *listDropletResponse
+		wantErr bool
+	}{
+
+		{
+			name: "simple parse",
+			args: args{data: []byte(`{
+  "droplets": [
+    {
+      "id": 3164444,
+      "name": "example.com",
+      "memory": 1024,
+      "vcpus": 1,
+      "status": "active",
+      "kernel": {
+        "id": 2233,
+        "name": "Ubuntu 14.04 x64 vmlinuz-3.13.0-37-generic",
+        "version": "3.13.0-37-generic"
+      },
+      "features": [
+        "backups",
+        "ipv6",
+        "virtio"
+      ],
+      "snapshot_ids": [],
+      "image": {
+        "id": 6918990,
+        "name": "14.04 x64",
+        "distribution": "Ubuntu",
+        "slug": "ubuntu-16-04-x64",
+        "public": true,
+        "regions": [
+          "nyc1"
+        ]
+      },
+      "size_slug": "s-1vcpu-1gb",
+      "networks": {
+        "v4": [
+          {
+            "ip_address": "104.236.32.182",
+            "netmask": "255.255.192.0",
+            "gateway": "104.236.0.1",
+            "type": "public"
+          }
+        ],
+        "v6": [
+          {
+            "ip_address": "2604:A880:0800:0010:0000:0000:02DD:4001",
+            "netmask": 64,
+            "gateway": "2604:A880:0800:0010:0000:0000:0000:0001",
+            "type": "public"
+          }
+        ]
+      },
+      "region": {
+        "name": "New York 3",
+        "slug": "nyc3",
+        "features": [
+          "private_networking",
+          "backups",
+          "ipv6"
+        ]
+      },
+      "tags": [
+        "tag1",
+        "tag2"
+      ],
+      "vpc_uuid": "f9b0769c-e118-42fb-a0c4-fed15ef69662"
+    }
+  ],
+  "links": {
+    "pages": {
+      "last": "https://api.digitalocean.com/v2/droplets?page=3&per_page=1",
+      "next": "https://api.digitalocean.com/v2/droplets?page=2&per_page=1"
+    }
+  }
+}`)},
+			want: &listDropletResponse{
+				Droplets: []droplet{
+					{
+						Image: struct {
+							Name string `json:"name"`
+							Slug string `json:"slug"`
+						}(struct {
+							Name string
+							Slug string
+						}{Name: "14.04 x64", Slug: "ubuntu-16-04-x64"}),
+						Region: struct {
+							Slug string `json:"slug"`
+						}(struct{ Slug string }{Slug: "nyc3"}),
+						Networks: networks{
+							V6: []network{
+								{
+									IPAddress: "2604:A880:0800:0010:0000:0000:02DD:4001",
+									Type:      "public",
+								},
+							},
+							V4: []network{
+								{
+									IPAddress: "104.236.32.182",
+									Type:      "public",
+								},
+							},
+						},
+						SizeSlug: "s-1vcpu-1gb",
+						Features: []string{"backups", "ipv6", "virtio"},
+						Tags:     []string{"tag1", "tag2"},
+						Status:   "active",
+						Name:     "example.com",
+						ID:       3164444,
+						VpcUUID:  "f9b0769c-e118-42fb-a0c4-fed15ef69662",
+					},
+				},
+				Links: links{
+					Pages: struct {
+						Last string `json:"last,omitempty"`
+						Next string `json:"next,omitempty"`
+					}(struct {
+						Last string
+						Next string
+					}{Last: "https://api.digitalocean.com/v2/droplets?page=3&per_page=1", Next: "https://api.digitalocean.com/v2/droplets?page=2&per_page=1"}),
+				},
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := parseAPIResponse(tt.args.data)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("parseAPIResponse() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("parseAPIResponse() got = \n%v\n, \nwant \n%v\n", got, tt.want)
+			}
+		})
+	}
+}
+
+func Test_getDroplets(t *testing.T) {
+	type args struct {
+		getAPIResponse func(string) ([]byte, error)
+	}
+	tests := []struct {
+		name             string
+		args             args
+		wantDropletCount int
+		wantErr          bool
+	}{
+		{
+			name: "get 4 droples",
+			args: args{
+				func(s string) ([]byte, error) {
+					var resp []byte
+					switch s {
+					case dropletsAPIPath:
+						// return next
+						resp = []byte(`{ "droplets": [
+    {
+      "id": 3164444,
+      "name": "example.com",
+      "status": "active",
+      "image": {
+        "id": 6918990,
+        "name": "14.04 x64",
+        "distribution": "Ubuntu",
+        "slug": "ubuntu-16-04-x64",
+        "public": true,
+        "regions": [
+          "nyc1"
+        ]
+      },
+      "size_slug": "s-1vcpu-1gb",
+      "networks": {
+        "v4": [
+          {
+            "ip_address": "104.236.32.182",
+            "netmask": "255.255.192.0",
+            "gateway": "104.236.0.1",
+            "type": "public"
+          }
+        ]
+      },
+      "region": {
+        "name": "New York 3",
+        "slug": "nyc3"
+      },
+      "tags": [
+        "tag1",
+        "tag2"
+      ],
+      "vpc_uuid": "f9b0769c-e118-42fb-a0c4-fed15ef69662"
+    },
+    {
+      "id": 3164444,
+      "name": "example.com",
+      "status": "active",
+      "image": {
+        "id": 6918990,
+        "name": "14.04 x64",
+        "distribution": "Ubuntu",
+        "slug": "ubuntu-16-04-x64"
+      },
+      "size_slug": "s-1vcpu-1gb",
+      "networks": {
+        "v4": [
+          {
+            "ip_address": "104.236.32.183",
+            "netmask": "255.255.192.0",
+            "gateway": "104.236.0.1",
+            "type": "public"
+          }
+        ]
+      },
+      "region": {
+        "name": "New York 3",
+        "slug": "nyc3"
+      },
+      "vpc_uuid": "f9b0769c-e118-42fb-a0c4-fed15ef69662"
+    },
+    {
+      "id": 3164444,
+      "name": "example.com",
+      "status": "active",
+      "image": {
+        "id": 6918990,
+        "name": "14.04 x64",
+        "distribution": "Ubuntu",
+        "slug": "ubuntu-16-04-x64"
+      },
+      "size_slug": "s-1vcpu-1gb",
+      "networks": {
+        "v4": [
+          {
+            "ip_address": "104.236.32.183",
+            "netmask": "255.255.192.0",
+            "gateway": "104.236.0.1",
+            "type": "public"
+          }
+        ]
+      },
+      "region": {
+        "name": "New York 3",
+        "slug": "nyc3"
+      },
+      "vpc_uuid": "f9b0769c-e118-42fb-a0c4-fed15ef69662"
+    }
+  ],
+  "links": {
+    "pages": {
+      "last": "https://api.digitalocean.com/v2/droplets?page=3&per_page=1",
+      "next": "https://api.digitalocean.com/v2/droplets?page=2&per_page=1"
+    }
+  }
+}`)
+					default:
+						// return with empty next
+						resp = []byte(`{ "droplets": [
+    {
+      "id": 3164444,
+      "name": "example.com",
+      "status": "active",
+      "image": {
+        "id": 6918990,
+        "name": "14.04 x64",
+        "distribution": "Ubuntu",
+        "slug": "ubuntu-16-04-x64"
+      },
+      "size_slug": "s-1vcpu-1gb",
+      "networks": {
+        "v4": [
+          {
+            "ip_address": "104.236.32.183",
+            "netmask": "255.255.192.0",
+            "gateway": "104.236.0.1",
+            "type": "public"
+          }
+        ]
+      },
+      "region": {
+        "name": "New York 3",
+        "slug": "nyc3"
+      },
+      "vpc_uuid": "f9b0769c-e118-42fb-a0c4-fed15ef69662"
+    },
+    {
+      "id": 3164444,
+      "name": "example.com",
+      "status": "active",
+      "image": {
+        "id": 6918990,
+        "name": "14.04 x64",
+        "distribution": "Ubuntu",
+        "slug": "ubuntu-16-04-x64"
+      },
+      "size_slug": "s-1vcpu-1gb",
+      "networks": {
+        "v4": [
+          {
+            "ip_address": "104.236.32.183",
+            "netmask": "255.255.192.0",
+            "gateway": "104.236.0.1",
+            "type": "public"
+          }
+        ]
+      },
+      "region": {
+        "name": "New York 3",
+        "slug": "nyc3"
+      },
+      "vpc_uuid": "f9b0769c-e118-42fb-a0c4-fed15ef69662"
+    }
+  ]
+}`)
+					}
+					return resp, nil
+				},
+			},
+			wantDropletCount: 5,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := getDroplets(tt.args.getAPIResponse)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("getDroplets() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if len(got) != tt.wantDropletCount {
+				t.Fatalf("unexpected droplets count: %d, want: %d, \n droplets: %v\n", len(got), tt.wantDropletCount, got)
+			}
+
+		})
+	}
+}

lib/promscrape/discovery/digitalocean/digitalocean.go

@@ -0,0 +1,148 @@
+package digitalocean
+
+import (
+	"fmt"
+	"net/url"
+	"strings"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promauth"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape/discoveryutils"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/proxy"
+)
+
+// SDConfig represents service discovery config for digital ocean.
+//
+// See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#digitalocean_sd_config
+type SDConfig struct {
+	Server            string                     `yaml:"server,omitempty"`
+	HTTPClientConfig  promauth.HTTPClientConfig  `yaml:",inline"`
+	ProxyURL          proxy.URL                  `yaml:"proxy_url,omitempty"`
+	ProxyClientConfig promauth.ProxyClientConfig `yaml:",inline"`
+	Port              int                        `yaml:"port,omitempty"`
+}
+
+// GetLabels returns Digital Ocean droplet labels according to sdc.
+func (sdc *SDConfig) GetLabels(baseDir string) ([]map[string]string, error) {
+	cfg, err := getAPIConfig(sdc, baseDir)
+	if err != nil {
+		return nil, fmt.Errorf("cannot get API config: %w", err)
+	}
+	droplets, err := getDroplets(cfg.client.GetAPIResponse)
+	if err != nil {
+		return nil, err
+	}
+
+	return addDropletLabels(droplets, cfg.port), nil
+}
+
+// https://developers.digitalocean.com/documentation/v2/#retrieve-an-existing-droplet-by-id
+type droplet struct {
+	ID     int    `json:"id"`
+	Name   string `json:"name"`
+	Status string `json:"status"`
+
+	Features []string `json:"features"`
+	Image    struct {
+		Name string `json:"name"`
+		Slug string `json:"slug"`
+	} `json:"image"`
+	SizeSlug string   `json:"size_slug"`
+	Networks networks `json:"networks"`
+	Region   struct {
+		Slug string `json:"slug"`
+	} `json:"region"`
+	Tags    []string `json:"tags"`
+	VpcUUID string   `json:"vpc_uuid"`
+}
+
+func (d *droplet) getIPByNet(netVersion, netType string) string {
+	var dropletNetworks []network
+	switch netVersion {
+	case "v4":
+		dropletNetworks = d.Networks.V4
+	case "v6":
+		dropletNetworks = d.Networks.V6
+	default:
+		logger.Fatalf("BUG, unexpected network type: %s, want v4 or v6", netVersion)
+	}
+	for _, net := range dropletNetworks {
+		if net.Type == netType {
+			return net.IPAddress
+		}
+	}
+	return ""
+}
+
+type networks struct {
+	V4 []network `json:"v4"`
+	V6 []network `json:"v6"`
+}
+type network struct {
+	IPAddress string `json:"ip_address"`
+	// private | public.
+	Type string `json:"type"`
+}
+
+// https://developers.digitalocean.com/documentation/v2/#list-all-droplets
+type listDropletResponse struct {
+	Droplets []droplet `json:"droplets,omitempty"`
+	Links    links     `json:"links,omitempty"`
+}
+
+type links struct {
+	Pages struct {
+		Last string `json:"last,omitempty"`
+		Next string `json:"next,omitempty"`
+	} `json:"pages,omitempty"`
+}
+
+func (r *listDropletResponse) nextURLPath() (string, error) {
+	if r.Links.Pages.Next == "" {
+		return "", nil
+	}
+	u, err := url.Parse(r.Links.Pages.Next)
+	if err != nil {
+		return "", fmt.Errorf("cannot parse digital ocean next url: %s, err: %s", r.Links.Pages.Next, err)
+	}
+	return u.RequestURI(), nil
+}
+
+func addDropletLabels(droplets []droplet, defaultPort int) []map[string]string {
+	var ms []map[string]string
+	for _, droplet := range droplets {
+		if len(droplet.Networks.V4) == 0 {
+			continue
+		}
+
+		privateIPv4 := droplet.getIPByNet("v4", "private")
+		publicIPv4 := droplet.getIPByNet("v4", "public")
+		publicIPv6 := droplet.getIPByNet("v6", "public")
+
+		addr := discoveryutils.JoinHostPort(publicIPv4, defaultPort)
+		m := map[string]string{
+			"__address__":                      addr,
+			"__meta_digitalocean_droplet_id":   fmt.Sprintf("%d", droplet.ID),
+			"__meta_digitalocean_droplet_name": droplet.Name,
+			"__meta_digitalocean_image":        droplet.Image.Slug,
+			"__meta_digitalocean_image_name":   droplet.Image.Name,
+			"__meta_digitalocean_private_ipv4": privateIPv4,
+			"__meta_digitalocean_public_ipv4":  publicIPv4,
+			"__meta_digitalocean_public_ipv6":  publicIPv6,
+			"__meta_digitalocean_region":       droplet.Region.Slug,
+			"__meta_digitalocean_size":         droplet.SizeSlug,
+			"__meta_digitalocean_status":       droplet.Status,
+			"__meta_digitalocean_vpc":          droplet.VpcUUID,
+		}
+		if len(droplet.Features) > 0 {
+			features := fmt.Sprintf(",%s,", strings.Join(droplet.Features, ","))
+			m["__meta_digitalocean_vpc"] = features
+		}
+		if len(droplet.Tags) > 0 {
+			tags := fmt.Sprintf(",%s,", strings.Join(droplet.Features, ","))
+			m["__meta_digitalocean_tags"] = tags
+		}
+		ms = append(ms, m)
+	}
+	return ms
+}

lib/promscrape/scraper.go

@@ -41,6 +41,9 @@ var (
 	dockerswarmSDCheckInterval = flag.Duration("promscrape.dockerswarmSDCheckInterval", 30*time.Second, "Interval for checking for changes in dockerswarm. "+
 		"This works only if dockerswarm_sd_configs is configured in '-promscrape.config' file. "+
 		"See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#dockerswarm_sd_config for details")
+	digitaloceanSDCheckInterval = flag.Duration("promscrape.digitaloceanSDCheckInterval", time.Minute, "Interval for checking for changes in digital ocean. "+
+		"This works only if digitalocean_sd_configs is configured in '-promscrape.config' file. "+
+		"See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#digitalocean_sd_config for details")
 	promscrapeConfigFile = flag.String("promscrape.config", "", "Optional path to Prometheus config file with 'scrape_configs' section containing targets to scrape. "+
 		"See https://docs.victoriametrics.com/#how-to-scrape-prometheus-exporters-such-as-node-exporter for details")
 	suppressDuplicateScrapeTargetErrors = flag.Bool("promscrape.suppressDuplicateScrapeTargetErrors", false, "Whether to suppress 'duplicate scrape target' errors; "+
@@ -111,6 +114,7 @@ func runScraper(configFile string, pushData func(wr *prompbmarshal.WriteRequest)
 	scs.add("ec2_sd_configs", *ec2SDCheckInterval, func(cfg *Config, swsPrev []*ScrapeWork) []*ScrapeWork { return cfg.getEC2SDScrapeWork(swsPrev) })
 	scs.add("gce_sd_configs", *gceSDCheckInterval, func(cfg *Config, swsPrev []*ScrapeWork) []*ScrapeWork { return cfg.getGCESDScrapeWork(swsPrev) })
 	scs.add("dockerswarm_sd_configs", *dockerswarmSDCheckInterval, func(cfg *Config, swsPrev []*ScrapeWork) []*ScrapeWork { return cfg.getDockerSwarmSDScrapeWork(swsPrev) })
+	scs.add("digitalocean_sd_configs", *digitaloceanSDCheckInterval, func(cfg *Config, swsPrev []*ScrapeWork) []*ScrapeWork { return cfg.getDigitalOceanDScrapeWork(swsPrev) })
 
 	var tickerCh <-chan time.Time
 	if *configCheckInterval > 0 {