Method Logs

protocols/cpc/filters/api.go:237–272

Logs creates a subscription that fires for all new log that match the given filter criteria.

(ctx context.Context, crit FilterCriteria)

// Logs creates a subscription that fires for all new log that match the given filter criteria.
func (api *PublicFilterAPI) Logs(ctx context.Context, crit FilterCriteria) (*rpc.Subscription, error) {
	notifier, supported := rpc.NotifierFromContext(ctx)
	if !supported {
		return &rpc.Subscription{}, rpc.ErrNotificationsUnsupported
	}

	var (
		rpcSub      = notifier.CreateSubscription()
		matchedLogs = make(chan []*types.Log)
	)

	logsSub, err := api.events.SubscribeLogs(cpchain.FilterQuery(crit), matchedLogs)
	if err != nil {
		return nil, err
	}

	go func() {

		for {
			select {
			case logs := <-matchedLogs:
				for _, log := range logs {
					notifier.Notify(rpcSub.ID, &log)
				}
			case <-rpcSub.Err(): // client send an unsubscribe request
				logsSub.Unsubscribe()
				return
			case <-notifier.Closed(): // connection dropped
				logsSub.Unsubscribe()
				return
			}
		}
	}()

	return rpcSub, nil
}

// FilterCriteria represents a request to create a new filter.
// Same as ethereum.FilterQuery but with UnmarshalJSON() method.