Method Dispatch

coderd/webpush/webpush.go:193–268

(ctx context.Context, userID uuid.UUID, msg codersdk.WebpushMessage)

}

func (n *Webpusher) Dispatch(ctx context.Context, userID uuid.UUID, msg codersdk.WebpushMessage) error {
	subscriptions, err := n.subscriptionsForUser(ctx, userID)
	if err != nil {
		return xerrors.Errorf("get web push subscriptions by user ID: %w", err)
	}
	if len(subscriptions) == 0 {
		return nil
	}

	msgJSON, err := json.Marshal(msg)
	if err != nil {
		return xerrors.Errorf("marshal webpush notification: %w", err)
	}

	cleanupSubscriptions := make([]uuid.UUID, 0)
	var mu sync.Mutex
	var eg errgroup.Group
	for _, subscription := range subscriptions {
		eg.Go(func() error {
			// TODO: Implement some retry logic here. For now, this is just a
			// best-effort attempt.
			statusCode, body, err := n.webpushSend(ctx, msgJSON, subscription.Endpoint, webpush.Keys{
				Auth:   subscription.EndpointAuthKey,
				P256dh: subscription.EndpointP256dhKey,
			})
			if err != nil {
				return xerrors.Errorf("send webpush notification: %w", err)
			}

			if isStaleSubscriptionStatus(statusCode) {
				// Remove subscriptions that the push service has marked as
				// permanently invalid (Apple returns 403 BadJwtToken and 404
				// for invalidated subscriptions, FCM returns 404 for
				// expired endpoints, all push services return 410 for
				// permanently gone subscriptions, and 400 indicates a
				// malformed subscription that cannot be retried). Without
				// this, stale rows accumulate after PWA reinstalls and the
				// in-memory cache keeps trying to deliver to dead
				// subscriptions.
				mu.Lock()
				cleanupSubscriptions = append(cleanupSubscriptions, subscription.ID)
				mu.Unlock()
			}

			if statusCode == http.StatusGone {
				// 410 Gone is informational, not a delivery error.
				return nil
			}

			// 200, 201, and 202 are common for successful delivery.
			if statusCode > http.StatusAccepted {
				// It's likely the subscription failed to deliver for some reason.
				return xerrors.Errorf("web push dispatch failed with status code %d: %s", statusCode, string(body))
			}

			return nil
		})
	}