Initial release

Signed-off-by: Marcus Noble <github@marcusnoble.co.uk>

pkg/metrics/devices.go

@@ -0,0 +1,72 @@
+package metrics
+
+import (
+	"fmt"
+	"tailscale-exporter/pkg/tailscale"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func collectDevices(client *tailscale.Client) []prometheus.Collector {
+	deviceExpiry := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "tailscale_devices_expiry_time",
+			Help: "The expiry time of devices authentication",
+			ConstLabels: prometheus.Labels{
+				"tailnet": client.GetTailnet(),
+			},
+		},
+		[]string{"id", "created", "name"},
+	)
+
+	deviceSecondsRemaining := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "tailscale_devices_expiry_seconds_remaining",
+			Help: "The number of seconds remaining until a device expires",
+			ConstLabels: prometheus.Labels{
+				"tailnet": client.GetTailnet(),
+			},
+		},
+		[]string{"id", "created", "name"},
+	)
+
+	deviceUpdateAvailable := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "tailscale_devices_update_available",
+			Help: "If the device can be updated (1) or is running the latest version of Tailscale (0)",
+			ConstLabels: prometheus.Labels{
+				"tailnet": client.GetTailnet(),
+			},
+		},
+		[]string{"id", "created", "name", "version"},
+	)
+
+	go func() {
+		for {
+			devices, err := client.GetDevices()
+			if err != nil {
+				fmt.Println("Failed to get devices: ", err)
+			} else {
+				for _, device := range devices {
+					if !device.KeyExpiryDisabled {
+						remainingSeconds := time.Until(device.Expires.Time).Seconds()
+
+						deviceExpiry.With(prometheus.Labels{"id": device.ID, "created": device.Created.String(), "name": device.Name}).Set(float64(device.Expires.Unix()))
+						deviceSecondsRemaining.With(prometheus.Labels{"id": device.ID, "created": device.Created.String(), "name": device.Name}).Set(remainingSeconds)
+					}
+
+					updateAvailable := 0.0
+					if device.UpdateAvailable {
+						updateAvailable = 1.0
+					}
+					deviceUpdateAvailable.With(prometheus.Labels{"id": device.ID, "created": device.Created.String(), "name": device.Name, "version": device.ClientVersion}).Set(updateAvailable)
+				}
+			}
+
+			time.Sleep(60 * time.Second)
+		}
+	}()
+
+	return []prometheus.Collector{deviceExpiry, deviceSecondsRemaining, deviceUpdateAvailable}
+}

pkg/metrics/keys.go

@@ -0,0 +1,56 @@
+package metrics
+
+import (
+	"fmt"
+	"tailscale-exporter/pkg/tailscale"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func collectKeys(client *tailscale.Client) []prometheus.Collector {
+	keyExpiry := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "tailscale_keys_expiry_time",
+			Help: "The expiry time of auth keys",
+			ConstLabels: prometheus.Labels{
+				"tailnet": client.GetTailnet(),
+			},
+		},
+		[]string{"id", "created", "description", "type"},
+	)
+
+	keySecondsRemaining := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "tailscale_keys_expiry_seconds_remaining",
+			Help: "The number of seconds remaining until a key expires",
+			ConstLabels: prometheus.Labels{
+				"tailnet": client.GetTailnet(),
+			},
+		},
+		[]string{"id", "created", "description", "type"},
+	)
+
+	go func() {
+		for {
+			keys, err := client.GetKeys()
+			if err != nil {
+				fmt.Println("Failed to get keys: ", err)
+			} else {
+				for _, key := range keys {
+					remainingSeconds := time.Until(key.Expires).Seconds()
+					keyType := "auth_key"
+					if key.Capabilities == nil {
+						keyType = "api_access_token"
+					}
+					keyExpiry.With(prometheus.Labels{"id": key.ID, "created": key.Created.String(), "description": key.Description, "type": keyType}).Set(float64(key.Expires.Unix()))
+					keySecondsRemaining.With(prometheus.Labels{"id": key.ID, "created": key.Created.String(), "description": key.Description, "type": keyType}).Set(remainingSeconds)
+				}
+			}
+
+			time.Sleep(60 * time.Second)
+		}
+	}()
+
+	return []prometheus.Collector{keyExpiry, keySecondsRemaining}
+}

pkg/metrics/metrics.go

@@ -0,0 +1,19 @@
+package metrics
+
+import (
+	"tailscale-exporter/pkg/tailscale"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/collectors"
+)
+
+var defaultCollectors = []prometheus.Collector{
+	collectors.NewGoCollector(),
+	collectors.NewProcessCollector(collectors.ProcessCollectorOpts{}),
+}
+
+func Collect(client *tailscale.Client, reg *prometheus.Registry) {
+	reg.MustRegister(defaultCollectors...)
+	reg.MustRegister(collectKeys(client)...)
+	reg.MustRegister(collectDevices(client)...)
+}

pkg/tailscale/client.go

@@ -0,0 +1,64 @@
+package tailscale
+
+import (
+	"context"
+	"fmt"
+	"os"
+
+	ts "github.com/tailscale/tailscale-client-go/tailscale"
+)
+
+type Client struct {
+	tsClient *ts.Client
+	tailnet  string
+	ctx      context.Context
+}
+
+func New() (*Client, error) {
+	apiKey := os.Getenv("TAILSCALE_API_KEY")
+	tailnet := os.Getenv("TAILSCALE_TAILNET")
+
+	if apiKey == "" {
+		return nil, fmt.Errorf("TAILSCALE_API_KEY must be set")
+	}
+	if tailnet == "" {
+		return nil, fmt.Errorf("TAILSCALE_TAILNET must be set")
+	}
+
+	client, err := ts.NewClient(apiKey, tailnet)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Client{
+		tsClient: client,
+		tailnet:  tailnet,
+		ctx:      context.Background(),
+	}, nil
+}
+
+func (c *Client) GetTailnet() string {
+	return c.tailnet
+}
+
+func (c *Client) GetKeys() ([]ts.Key, error) {
+	allKeys := []ts.Key{}
+
+	keys, err := c.tsClient.Keys(c.ctx)
+	if err != nil {
+		return nil, err
+	} else {
+		for _, k := range keys {
+			key, err := c.tsClient.GetKey(c.ctx, k.ID)
+			if err != nil {
+				return nil, err
+			}
+			allKeys = append(allKeys, key)
+		}
+	}
+	return allKeys, nil
+}
+
+func (c *Client) GetDevices() ([]ts.Device, error) {
+	return c.tsClient.Devices(c.ctx)
+}