Merge pull request #2306 from mysteriumnetwork/force-settle-on-balanc…

…e-exhaust

Force settle if balance exhausted

session/pingpong/accountant_promise_settler.go

@@ -200,10 +200,22 @@ func (aps *accountantPromiseSettler) Subscribe() error {
 		return errors.Wrap(err, "could not subscribe to service status event")
 	}
 
+	err = aps.eventBus.SubscribeAsync(event.AppTopicSettlementRequest, aps.handleSettlementEvent)
+	if err != nil {
+		return errors.Wrap(err, "could not subscribe to settlement event")
+	}
+
 	err = aps.eventBus.SubscribeAsync(event.AppTopicAccountantPromise, aps.handleAccountantPromiseReceived)
 	return errors.Wrap(err, "could not subscribe to accountant promise event")
 }
 
+func (aps *accountantPromiseSettler) handleSettlementEvent(event event.AppEventSettlementRequest) {
+	err := aps.ForceSettle(event.ProviderID, event.AccountantID)
+	if err != nil {
+		log.Error().Err(err).Msg("could not settle promise")
+	}
+}
+
 func (aps *accountantPromiseSettler) handleServiceEvent(event servicestate.AppEventServiceStatus) {
 	switch event.Status {
 	case string(servicestate.Running):

session/pingpong/event/event.go

@@ -32,8 +32,16 @@ const (
 	AppTopicEarningsChanged = "earnings_change"
 	// AppTopicInvoicePaid is a topic for publish events exchange message send to provider as a consumer.
 	AppTopicInvoicePaid = "invoice_paid"
+	// AppTopicSettlementRequest forces the settlement of promises for given provider/accountant.
+	AppTopicSettlementRequest = "settlement_request"
 )
 
+// AppEventSettlementRequest represents the payload that is sent on the AppTopicSettlementRequest topic.
+type AppEventSettlementRequest struct {
+	AccountantID common.Address
+	ProviderID   identity.Identity
+}
+
 // AppEventAccountantPromise represents the payload that is sent on the AppTopicAccountantPromise.
 type AppEventAccountantPromise struct {
 	Promise      crypto.Promise

session/pingpong/invoice_tracker.go

@@ -35,6 +35,7 @@ import (
 	"github.com/mysteriumnetwork/node/market"
 	"github.com/mysteriumnetwork/node/p2p"
 	sessionEvent "github.com/mysteriumnetwork/node/session/event"
+	"github.com/mysteriumnetwork/node/session/pingpong/event"
 	"github.com/mysteriumnetwork/payments/crypto"
 	"github.com/pkg/errors"
 	"github.com/rs/zerolog/log"
@@ -546,6 +547,16 @@ func (it *InvoiceTracker) handleAccountantError(err error) error {
 		stdErr.Is(err, ErrConsumerUnregistered):
 		// these are critical, return and cancel session
 		return err
+	// under normal use, this should not occur. If it does, we should drop sessions until we settle because we're not getting paid.
+	case stdErr.Is(err, ErrAccountantProviderBalanceExhausted):
+		it.deps.EventBus.Publish(
+			event.AppTopicSettlementRequest,
+			event.AppEventSettlementRequest{
+				AccountantID: it.deps.ProvidersAccountantID,
+				ProviderID:   it.deps.ProviderID,
+			},
+		)
+		return err
 	default:
 		log.Err(err).Msgf("unknown accountant error encountered")
 		return err