Incorrect subscription behavior

[voodoo-dn]

Hi. When I use subscription from Playground, all works perfectly. But when I subscribe via Apollo Client, on server side I see:

1. subscribed ...
2. message received ...
3. message published ...
4. channel close reason: context cancelled
5. channel closed: ...
6. Go to step 1

I dont understand why. Client side done by apollo documentation. Maybe problem in server?

Thanks.

func (r *SubscriptionResolver) BalanceUpdate(ctx context.Context) (<-chan *model.BalanceUpdateEvent, error) {
	authenticatedUserID, err := r.userProvider.AuthenticatedUserID(ctx)
	if err != nil {
		return nil, err
	}

	subscriptionID := uuid.New()

	channelName, err := r.channelName(walletBalanceUpdateChannel, authenticatedUserID)
	if err != nil {
		return nil, err
	}

	balanceUpdateChan := make(chan *model.BalanceUpdateEvent, 1)

	pubSub := r.subscribe(ctx, channelName)

	r.logger.Infof("subscribed: %s", subscriptionID.String())

	go func() {
		for {
			select {
			case message := <-pubSub.Channel():
				r.logger.Infof("message received: %s", subscriptionID.String())

				e := event.WalletBalanceUpdate{}

				if err := errors.WithStack(r.thriftDeserializer.ReadString(&e, message.Payload)); err != nil {
					r.logger.
						WithError(err).
						WithField("message", message.Payload).
						Error(err)
					continue
				}

				balanceUpdateChan <- &model.BalanceUpdateEvent{
					WalletID: string(e.WalletId),
					Amount:   e.Amount,
				}
				r.logger.Infof("message published: %s", subscriptionID.String())
			case <-ctx.Done():
				r.logger.Infof("channel close reason: %s", ctx.Err())
				close(balanceUpdateChan)
				if err := pubSub.Unsubscribe(channelName); err != nil {
					r.logger.WithError(errors.WithStack(err)).Error(err)
				}
				r.logger.Infof("channel closed: %s", subscriptionID.String())
				return
			}
		}
	}()

	return balanceUpdateChan, nil
}

func (r *SubscriptionResolver) subscribe(
	ctx context.Context,
	channel string,
) *redis.PubSub {
	return r.redisClient.WithContext(ctx).Subscribe(channel)
}

func (r *SubscriptionResolver) channelName(channelType channelType, userID uuid.UUID) (string, error) {
	var channelPrefix string

	switch channelType {
	case walletBalanceUpdateChannel:
		channelPrefix = "wallet_balance_update"
	default:
		return "", errors.Errorf("unsupported channel type %d", channelType)
	}

	return fmt.Sprintf("%s:%s", channelPrefix, userID.String()), nil
}

versions

• gqlgen version? 0.15.0
• go version? 1.15.2
• dep or go modules?

[NateScarlet]

Isn't the latest gqlgen 0.13.0?

Maybe context cancelled is because client closed the connection.