restructure the API and update the admin script

api/status/service.go

@@ -0,0 +1,105 @@
+package status
+
+import (
+	"net/http"
+	"net/http/httptrace"
+	"net/url"
+	"time"
+
+	"github.com/ngn13/website/api/database"
+	"github.com/ngn13/website/api/util"
+)
+
+const (
+	STATUS_RES_DOWN = 0 // service is down
+	STATUS_RES_OK   = 1 // service is up
+	STATUS_RES_SLOW = 2 // service is up, but slow
+	STATUS_RES_NONE = 3 // service doesn't support status checking/status checking is disabled
+)
+
+func (s *Type) check_http_service(service *database.Service) (r uint8, err error) {
+	var (
+		req *http.Request
+		res *http.Response
+
+		start   time.Time
+		elapsed time.Duration
+	)
+
+	r = STATUS_RES_NONE
+
+	if req, err = http.NewRequest("GET", service.CheckURL, nil); err != nil {
+		return
+	}
+
+	trace := &httptrace.ClientTrace{
+		GetConn:              func(_ string) { start = time.Now() },
+		GotFirstResponseByte: func() { elapsed = time.Since(start) },
+	}
+
+	http.DefaultClient.Timeout = s.timeout
+	req = req.WithContext(httptrace.WithClientTrace(req.Context(), trace))
+	res, err = http.DefaultClient.Do(req)
+
+	if res != nil {
+		defer res.Body.Close()
+	}
+
+	if err != nil {
+		util.Debg("marking service \"%s\" as down (%s)", service.Name, err.Error())
+		err = nil
+		r = STATUS_RES_DOWN
+	} else if res.StatusCode != 200 {
+		util.Debg("marking service \"%s\" as down (status code %d)", service.Name, res.StatusCode)
+		r = STATUS_RES_DOWN
+	} else if elapsed.Microseconds() > s.limit.Microseconds() {
+		r = STATUS_RES_SLOW
+	} else {
+		r = STATUS_RES_OK
+	}
+
+	return
+}
+
+func (s *Type) check_service(service *database.Service) error {
+	var (
+		res uint8
+		url *url.URL
+		err error
+	)
+
+	if s.disabled || service.CheckURL == "" {
+		err = nil
+		goto fail
+	}
+
+	if url, err = url.Parse(service.CheckURL); err != nil {
+		return err
+	}
+
+	switch url.Scheme {
+	case "https":
+		if res, err = s.check_http_service(service); err != nil {
+			goto fail
+		}
+
+	case "http":
+		if res, err = s.check_http_service(service); err != nil {
+			goto fail
+		}
+
+	default:
+		// unsupported protocol
+		err = nil
+		goto fail
+	}
+
+	service.CheckTime = uint64(time.Now().Unix())
+	service.CheckRes = res
+	return nil
+
+fail:
+	service.CheckTime = 0
+	service.CheckRes = STATUS_RES_NONE
+	return err
+}