fix: throttle wakatime api requests (attempt to fix #152)

services/imports/wakatime.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/base64"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"github.com/emvi/logbuch"
 	"github.com/muety/wakapi/config"
@@ -17,7 +18,13 @@ import (
 )
 
 const OriginWakatime = "wakatime"
-const maxWorkers = 6
+const (
+	// wakatime api permits a max. rate of 10 req / sec
+	// https://github.com/wakatime/wakatime/issues/261
+	// with 5 workers, each sleeping slightly over 1/2 sec after every req., we should stay well below that limit
+	maxWorkers    = 5
+	throttleDelay = 550 * time.Millisecond
+)
 
 type WakatimeHeartbeatImporter struct {
 	ApiKey string
@@ -72,6 +79,7 @@ func (w *WakatimeHeartbeatImporter) Import(user *models.User, minFrom time.Time,
 
 			go func(day time.Time) {
 				defer sem.Release(1)
+				defer time.Sleep(throttleDelay)
 
 				d := day.Format(config.SimpleDateFormat)
 				heartbeats, err := w.fetchHeartbeats(d)
@@ -113,6 +121,8 @@ func (w *WakatimeHeartbeatImporter) fetchHeartbeats(day string) ([]*wakatime.Hea
 	res, err := httpClient.Do(w.withHeaders(req))
 	if err != nil {
 		return nil, err
+	} else if res.StatusCode >= 400 {
+		return nil, errors.New(fmt.Sprintf("got status %d from wakatime api", res.StatusCode))
 	}
 
 	var heartbeatsData wakatime.HeartbeatsViewModel