package main
import (
"fmt"
"io/ioutil"
"net/http"
"os"
"time"
"gopkg.in/alecthomas/kingpin.v2"
"gopkg.in/yaml.v2"
hue "github.com/collinux/gohue"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promhttp"
"github.com/prometheus/common/log"
"github.com/prometheus/common/version"
)
const namespace = "hue"
var (
app = kingpin.New("hue_exporter", "A Prometheus exporter for Philips Hue.")
showVersion = app.Flag("version", "Print the version and exit.").Short('V').Bool()
run = app.Command("run", "Run the exporter.").Default()
// TODO: update https://github.com/prometheus/prometheus/wiki/Default-port-allocations
addr = run.Flag("listen.address", "The address to listen on for HTTP requests.").Short('l').Default(":9366").TCP()
config = run.Flag("config.file", "The config file to use.").Short('c').Default("hue_exporter.yml").ExistingFile()
generate = app.Command("generate", "Generate configuration for Hue exporter.")
output = generate.Flag("output.file", "The output file to use.").Short('o').Default("hue_exporter.yml").String()
)
type Config struct {
IPAddr string `yaml:"ip_address"`
APIKey string `yaml:"api_key"`
SensorConfig struct {
IgnoreTypes []string `yaml:"ignore_types"`
MatchNames bool `yaml:"match_names"`
} `yaml:"sensors"`
}
// Bridge is an interface for the bridge struct from Collinux/gohue to allow stubbing in tests
type Bridge interface {
Login(string) error
GetAllSensors() ([]hue.Sensor, error)
GetAllLights() ([]hue.Light, error)
GetAllGroups() ([]hue.Group, error)
}
func readConfig(raw []byte, cfg *Config) {
err := yaml.Unmarshal(raw, cfg)
if err != nil {
log.Fatalf("Error parsing config file: %v\n", err)
}
}
func newBridge(ipAddr string) Bridge {
bridge, err := hue.NewBridge(ipAddr)
if err != nil {
log.Fatalf("Error connecting to Hue bridge at %v: %v\n", ipAddr, err)
}
return bridge
}
func setupPrometheus(bridge Bridge, cfg *Config) {
err := bridge.Login((*cfg).APIKey)
if err != nil {
log.Fatalf("Error authenticating with Hue bridge at %v: %v\n", (*cfg).IPAddr, err)
}
prometheus.MustRegister(NewGroupCollector(namespace, bridge))
prometheus.MustRegister(NewLightCollector(namespace, bridge))
prometheus.MustRegister(NewSensorCollector(namespace, bridge, (*cfg).SensorConfig.IgnoreTypes, (*cfg).SensorConfig.MatchNames))
prometheus.MustRegister(version.NewCollector("hue_exporter"))
}
func listen() {
http.Handle("/metrics", promhttp.Handler())
http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte(`<html>
<head><title>Hue Exporter</title></head>
<body>
<h1>Hue Exporter</h1>
<p><a href="/metrics">Metrics</a></p>
</body>
</html>`))
})
srv := &http.Server{
Addr: (*addr).String(),
ReadTimeout: 5 * time.Second,
WriteTimeout: 10 * time.Second,
ErrorLog: log.NewErrorLogger(),
}
log.Infoln("Listening on", (*addr).String())
log.Fatal(srv.ListenAndServe())
}
func runServer() {
var cfg Config
raw, err := ioutil.ReadFile(*config)
if err != nil {
log.Fatalf("Error reading config file: %v\n", err)
}
readConfig(raw, &cfg)
bridge := newBridge(cfg.IPAddr)
setupPrometheus(bridge, &cfg)
listen()
}
func main() {
log.AddFlags(app)
command := kingpin.MustParse(app.Parse(os.Args[1:]))
if *showVersion {
fmt.Fprintln(os.Stdout, version.Print("hue_exporter"))
} else {
log.Infoln("Starting hue_exporter", version.Info())
log.Infoln("Build context", version.BuildContext())
switch command {
case run.FullCommand():
runServer()
case generate.FullCommand():
generateConfig(output)
}
}
}