reject request if backfeed channel is overloaded

main.go

@@ -65,7 +65,7 @@ func (that *ProjectBackfeedManager) RedisConfigDiffers(new *ProjectRedisConfig)
 	return that.ProjectConfig.RedisConfig == nil || new == nil || *that.ProjectConfig.RedisConfig != *new
 }
 
-func (that *ProjectBackfeedManager) PushItem(ctx context.Context, item *BackfeedItem) bool {
+func (that *ProjectBackfeedManager) PushItem(ctx context.Context, item *BackfeedItem) error {
 	//that.Lock.RLock()
 	//defer that.Lock.RUnlock()
 	//if that.C == nil {
@@ -73,11 +73,13 @@ func (that *ProjectBackfeedManager) PushItem(ctx context.Context, item *Backfeed
 	//}
 	select {
 	case <-ctx.Done():
-		return false
+		return ctx.Err()
 	case <-that.Context.Done():
-		return false
+		return fmt.Errorf("backfeed channel closed")
 	case that.C <- item:
-		return true
+		return nil
+	default:
+		return fmt.Errorf("backfeed channel full")
 	}
 }
 
@@ -424,7 +426,6 @@ func (that *GlobalBackfeedManager) HandleLegacy(res http.ResponseWriter, req *ht
 	scanner := bufio.NewScanner(req.Body)
 	scanner.Split(splitter.Split)
 
-	var err error
 	statusCode := http.StatusNoContent
 	n := 0
 	for scanner.Scan() {
@@ -439,25 +440,19 @@ func (that *GlobalBackfeedManager) HandleLegacy(res http.ResponseWriter, req *ht
 			SecondaryShard: secondaryShard,
 			Item:           bcopy,
 		}
-		ok := projectBackfeedManager.PushItem(req.Context(), item)
-		if !ok {
-			err = fmt.Errorf("channel closed")
-			statusCode = http.StatusServiceUnavailable
-			break
-		}
-		n++
-	}
-	if err == nil {
-		err = scanner.Err()
+		err := projectBackfeedManager.PushItem(req.Context(), item)
 		if err != nil {
-			statusCode = http.StatusBadRequest
+			WriteResponse(res, http.StatusServiceUnavailable, err)
+			return
 		}
+		n++
 	}
+	err := scanner.Err()
 	if err != nil {
 		WriteResponse(res, statusCode, err)
-	} else {
-		WriteResponse(res, http.StatusOK, fmt.Sprintf("%d items queued for deduplication", n))
+		return
 	}
+	WriteResponse(res, http.StatusOK, fmt.Sprintf("%d items queued for deduplication", n))
 	return
 }