package main import ( "fmt" "log" "net/http" "net/url" "os" "strings" "time" "github.com/arriqaaq/scraper" "github.com/gorilla/mux" ) var ( // server settings port = 8080 readTimeout = 5 * time.Second writeTimeout = 5 * time.Second // targets to scrape targets []*scraper.Target // scraper settings storeSize = 10 ) // healthzHandler for reporting health func healthzHandler(w http.ResponseWriter, r *http.Request) { switch r.Method { case http.MethodGet: w.WriteHeader(http.StatusOK) w.Write([]byte("OK")) break default: w.WriteHeader(http.StatusMethodNotAllowed)	} } func parseURLs(urls []string) []*scraper.Target { var targets []*scraper.Target for _, u := range urls { u, err := url.ParseRequestURI(u) if err != nil { continue	} targets = append(targets, scraper.NewTarget(u))	} return targets } func main() { //Read URLs to monitor from environment variable var urls = []string{"http://google.com", "http://cloudflare.com", "http://reddit.com"} targets = parseURLs(urls) fmt.Printf("URLs to monitor: %+v\n", targets) scrapePool, err := scraper.NewScrapePool( &scraper.ScrapeConfig{ ScrapeInterval: time.Duration(3 * time.Second), ScrapeTimeout: time.Duration(2 * time.Second), StoreSize: storeSize,	},	) if err != nil { panic(err)	} scraper.RegisterExporter(scrapePool) // start scraping the targets scrapePool.Start(targets) // create Router router := mux.NewRouter() // register handlers router.Handle("/metrics", scraper.PrometheusHandler()) router.HandleFunc("/healthz", healthzHandler) // configure the HTTP server and start it s := &http.Server{ Addr: fmt.Sprintf(":%d", port), ReadTimeout: readTimeout, WriteTimeout: writeTimeout, MaxHeaderBytes: http.DefaultMaxHeaderBytes, Handler: router,	} log.Fatal(s.ListenAndServe()) }