✨ [client] Watch virtual channel

Signed-off-by: Matthias Geihs <[email protected]>

client/virtual_channel.go

@@ -100,6 +100,52 @@ func (c *Client) handleVirtualChannelFundingProposal(
 	c.acceptProposal(responder)
 }
 
+func (c *Channel) watchVirtual() error {
+	log := c.Log().WithField("proc", fmt.Sprintf("virtual channel watcher %v", c.ID()))
+	defer log.Info("Watcher returned.")
+
+	// Subscribe to state changes
+	ctx := c.Ctx()
+	sub, err := c.adjudicator.Subscribe(ctx, c.Params())
+	if err != nil {
+		return errors.WithMessage(err, "subscribing to adjudicator state changes")
+	}
+	defer func() {
+		err := sub.Close()
+		if err != nil {
+			log.Warn(err)
+		}
+	}()
+
+	// Wait for state changed event
+	for e := sub.Next(); e != nil; e = sub.Next() {
+		log.Debugf("event %v", e)
+
+		// Update channel
+		switch e := e.(type) {
+		case *channel.RegisteredEvent:
+			if e.Version() > c.State().Version {
+				err := c.client.updateVirtualChannelState(ctx, e.State, e.Sigs)
+				if err != nil {
+					log.Warnf("error updating virtual channel: %v", err)
+				}
+			}
+
+		case *channel.ProgressedEvent:
+			log.Infof("Virtual channel progressed: %v", e.ID())
+
+		case *channel.ConcludedEvent:
+			log.Infof("Virtual channel concluded: %v", e.ID())
+
+		default:
+			log.Errorf("unsupported type: %T", e)
+		}
+	}
+
+	err = sub.Err()
+	log.Debugf("Subscription closed: %v", err)
+	return errors.WithMessage(err, "subscription closed")
+}
 
 type dummyAccount struct {
 	address wallet.Address
@@ -306,6 +352,12 @@ func (c *Client) matchFundingProposal(a, b interface{}) (ok bool) {
 		return false
 	}
 	c.channels.Put(virtual.ID(), virtual)
+
+	// Watch.
+	go func() {
+		err := virtual.watchVirtual()
+		c.log.Debugf("channel %v: watcher stopped: %v", virtual.ID(), err)
+	}()
 	return
 }