Add support for device discovery and additional devices (#34)

* add logging for unrecognized device type

* Implement device discovery for prometheus http service discovery

* Log temp/humidity for remaining sensors that provide them

* Ignore vscode settings

* Use map instead of switch to filter supported device types

* sort supported device types by name

* update readme for new supported device types and service discovery feature

* Separate config examples for static and dynamic

* end .gitignore with newline

* user simpler syntax for creating supportedDeviceTypes

* fix dockerfile case warning

=> WARN: FromAsCasing: 'as' and 'FROM' keywords' casing do not match (line 1)

.gitignore

@@ -0,0 +1,2 @@
+# ignore vscode settings
+.vscode/

Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.22 as build
+FROM golang:1.22 AS build
 COPY . .
 RUN GOPATH="" CGO_ENABLED=0 go build -o /switchbot_exporter
 

README.md

@@ -1,22 +1,28 @@
 # switchbot-exporter
 
+Exports [switchbot](https://us.switch-bot.com) device metrics for [prometheus](https://prometheus.io).
+
 ## Supported Devices / Metrics
 
+Currently supports humidity and temperature for:
+* Hub 2
+* Humidifier
 * Meter
-  * humidity
-  * temperature
 * Meter Plus
-  * humidity
-  * temperature
+* Indoor/Outdoor Thermo-Hygrometer
+
+Supports weight and voltage for:
 * Plug Mini (JP)
-  * weight
-  * voltage
 
 ## Prometheus Configuration
 
-The switchbot exporter needs to be passed the target ID as a parameter, this can be done with relabelling (like [blackbox exporter](https://github.com/prometheus/blackbox_exporter))
+### Static Configuration
+
+The switchbot exporter needs to be passed the target ID as a parameter, this can be done with relabelling (like [blackbox exporter](https://github.com/prometheus/blackbox_exporter)).
 
-Example Config:
+Change the host:port in the relabel_configs `replacement` to the host:port where the exporter is listening.
+
+#### Example Config (Static Configs):
 
 ``` yaml
 scrape_configs:
@@ -34,7 +40,33 @@ scrape_configs:
       - target_label: __address__
         replacement: 127.0.0.1:8080 # The switchbot exporter's real ip/port
 ```
+### Dynamic Configuration using Service Discovery
+
+The switchbot exporter also implements http service discovery to create a prometheus target for each supported device in your account.  When using service discover, the `static_configs` is not needed.  Relabeling is used (see [blackbox exporter](https://github.com/prometheus/blackbox_exporter)) to convert the device's id into a url with the id as the url's target query parameter.
+
+Change the host:port in the http_sd_configs `url` and in the relabel_configs `replacement` to the host:port where the exporter is listening.
+
+#### Example Config (Dynamic Configs):
+
+``` yaml
+scrape_configs:
+  - job_name: 'switchbot'
+    scrape_interval: 5m # not to reach API rate limit
+    metrics_path: /metrics
+    http_sd_configs:
+    - url: http://127.0.0.1:8080/discover
+      refresh_interval: 1d # no need to check for new devices very often
+    relabel_configs:
+      - source_labels: [__address__]
+        target_label: __param_target
+      - source_labels: [__param_target]
+        target_label: instance
+      - target_label: __address__
+        replacement: 127.0.0.1:8080 # The switchbot exporter's real ip/port
+```
 
 ## Limitation
 
+Only a subset of switchbot devices are currently supported.
+
 [switchbot API's request limit](https://github.com/OpenWonderLabs/SwitchBotAPI#request-limit)

main.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"context"
+	"encoding/json"
 	"errors"
 	"flag"
 	"fmt"
@@ -28,6 +29,12 @@ var deviceLabels = prometheus.NewGaugeVec(prometheus.GaugeOpts{
 	Name:      "device",
 }, []string{"device_id", "device_name"})
 
+// the type expected by the prometheus http service discovery
+type StaticConfig struct {
+	Targets []string          `json:"targets"`
+	Labels  map[string]string `json:"labels"`
+}
+
 func main() {
 	flag.Parse()
 	if err := run(); err != nil {
@@ -86,6 +93,51 @@ func run() error {
 		}
 	}()
 
+	http.HandleFunc("/discover", func(w http.ResponseWriter, r *http.Request) {
+		log.Printf("discovering devices...")
+		devices, _, err := sc.Device().List(r.Context())
+		if err != nil {
+			http.Error(w, fmt.Sprintf("failed to discover devices: %s", err), http.StatusInternalServerError)
+			return
+		}
+		log.Printf("discovered device count: %d", len(devices))
+
+		supportedDeviceTypes := map[switchbot.PhysicalDeviceType]struct{}{
+			switchbot.Hub2:       {},
+			switchbot.Humidifier: {},
+			switchbot.Meter:      {},
+			switchbot.MeterPlus:  {},
+			switchbot.PlugMiniJP: {},
+			switchbot.WoIOSensor: {},
+		}
+
+		data := make([]StaticConfig, len(devices))
+
+		for i, device := range devices {
+			_, deviceTypeIsSupported := supportedDeviceTypes[device.Type]
+			if !deviceTypeIsSupported {
+				log.Printf("ignoring device %s with unsupported type: %s", device.ID, device.Type)
+				continue
+			}
+
+			log.Printf("discovered device %s of type %s", device.ID, device.Type)
+			staticConfig := StaticConfig{}
+			staticConfig.Targets = make([]string, 1)
+			staticConfig.Labels = make(map[string]string)
+
+			staticConfig.Targets[0] = device.ID
+			staticConfig.Labels["device_id"] = device.ID
+			staticConfig.Labels["device_name"] = device.Name
+			staticConfig.Labels["device_type"] = string(device.Type)
+
+			data[i] = staticConfig
+		}
+
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		json.NewEncoder(w).Encode(data)
+	})
+
 	http.HandleFunc("/-/reload", func(w http.ResponseWriter, r *http.Request) {
 		if expectMethod := http.MethodPost; r.Method != expectMethod {
 			w.WriteHeader(http.StatusMethodNotAllowed)
@@ -109,14 +161,16 @@ func run() error {
 			return
 		}
 
+		log.Printf("getting device status: %s", target)
 		status, err := sc.Device().Status(r.Context(), target)
 		if err != nil {
 			log.Printf("getting device status: %v", err)
 			return
 		}
+		log.Printf("got device status: %s", target)
 
 		switch status.Type {
-		case switchbot.Meter, switchbot.MeterPlus:
+		case switchbot.Meter, switchbot.MeterPlus, switchbot.Hub2, switchbot.WoIOSensor, switchbot.Humidifier:
 			meterHumidity := prometheus.NewGaugeVec(prometheus.GaugeOpts{
 				Namespace: "switchbot",
 				Subsystem: "meter",
@@ -158,6 +212,8 @@ func run() error {
 			plugWeight.WithLabelValues(status.ID).Set(status.Weight)
 			plugVoltage.WithLabelValues(status.ID).Set(status.Voltage)
 			plugElectricCurrent.WithLabelValues(status.ID).Set(status.ElectricCurrent)
+		default:
+			log.Printf("unrecognized device type: %s", status.Type)
 		}
 
 		promhttp.HandlerFor(registry, promhttp.HandlerOpts{}).ServeHTTP(w, r)
@@ -191,6 +247,7 @@ func reloadDevices(sc *switchbot.Client) error {
 	if err != nil {
 		return fmt.Errorf("getting device list: %w", err)
 	}
+	log.Print("got device list")
 
 	for _, device := range devices {
 		deviceLabels.WithLabelValues(device.ID, device.Name).Set(0)