routing: remove route hop maps

Hop maps were used in a test to verify the population of the hop map
itself and further only in a single function (getFailedChannelID).
Rewrote that function and removed the hop maps completely.
This commit is contained in:
Joost Jager 2018-11-29 16:36:37 +01:00
parent 42debc6c12
commit 8b8e82a171
No known key found for this signature in database
GPG Key ID: AE6B0D042C8E38D9
3 changed files with 37 additions and 91 deletions

@ -146,6 +146,10 @@ type Route struct {
// amount of fees.
TotalAmount lnwire.MilliSatoshi
// SourcePubKey is the pubkey of the node where this route originates
// from.
SourcePubKey Vertex
// Hops contains details concerning the specific forwarding details at
// each hop.
Hops []*Hop
@ -158,16 +162,6 @@ type Route struct {
// is present in this route or not. Channels are identified by the
// uint64 version of the short channel ID.
chanIndex map[uint64]struct{}
// nextHop maps a node, to the next channel that it will pass the HTLC
// off to. With this map, we can easily look up the next outgoing
// channel or node for pruning purposes.
nextHopMap map[Vertex]*Hop
// prevHop maps a node, to the channel that was directly before it
// within the route. With this map, we can easily look up the previous
// channel or node for pruning purposes.
prevHopMap map[Vertex]*Hop
}
// HopFee returns the fee charged by the route hop indicated by hopIndex.
@ -183,29 +177,6 @@ func (r *Route) HopFee(hopIndex int) lnwire.MilliSatoshi {
return incomingAmt - r.Hops[hopIndex].AmtToForward
}
// nextHopVertex returns the next hop (by Vertex) after the target node. If the
// target node is not found in the route, then false is returned.
func (r *Route) nextHopVertex(n *btcec.PublicKey) (Vertex, bool) {
hop, ok := r.nextHopMap[NewVertex(n)]
return Vertex(hop.PubKeyBytes), ok
}
// nextHopChannel returns the uint64 channel ID of the next hop after the
// target node. If the target node is not found in the route, then false is
// returned.
func (r *Route) nextHopChannel(n *btcec.PublicKey) (*Hop, bool) {
hop, ok := r.nextHopMap[NewVertex(n)]
return hop, ok
}
// prevHopChannel returns the uint64 channel ID of the before hop after the
// target node. If the target node is not found in the route, then false is
// returned.
func (r *Route) prevHopChannel(n *btcec.PublicKey) (*Hop, bool) {
hop, ok := r.prevHopMap[NewVertex(n)]
return hop, ok
}
// containsNode returns true if a node is present in the target route, and
// false otherwise.
func (r *Route) containsNode(v Vertex) bool {
@ -381,31 +352,21 @@ func NewRouteFromHops(amtToSend lnwire.MilliSatoshi, timeLock uint32,
// that is send from the source and the final amount that is received
// by the destination.
route := &Route{
SourcePubKey: sourceVertex,
Hops: hops,
TotalTimeLock: timeLock,
TotalAmount: amtToSend,
TotalFees: amtToSend - hops[len(hops)-1].AmtToForward,
nodeIndex: make(map[Vertex]struct{}),
chanIndex: make(map[uint64]struct{}),
nextHopMap: make(map[Vertex]*Hop),
prevHopMap: make(map[Vertex]*Hop),
}
// Then we'll update the node and channel index, to indicate that this
// Vertex and incoming channel link are present within this route.
// Also, the prev and next hop maps will be populated.
prevNode := sourceVertex
for i := 0; i < len(hops); i++ {
hop := hops[i]
for _, hop := range hops {
v := Vertex(hop.PubKeyBytes)
route.nodeIndex[v] = struct{}{}
route.chanIndex[hop.ChannelID] = struct{}{}
route.prevHopMap[v] = hop
route.nextHopMap[prevNode] = hop
prevNode = v
}
return route

@ -845,35 +845,6 @@ func testBasicGraphPathFindingCase(t *testing.T, graphInstance *testGraphInstanc
t.Fatalf("expected time lock of %v, instead have %v", 2,
route.TotalTimeLock)
}
// The next and prev hop maps should be properly set.
for i := 0; i < expectedHopCount; i++ {
prevChan, ok := route.prevHopChannel(aliases[expectedHops[i].alias])
if !ok {
t.Fatalf("hop didn't have prev chan but should have")
}
if prevChan.ChannelID != route.Hops[i].ChannelID {
t.Fatalf("incorrect prev chan: expected %v, got %v",
prevChan.ChannelID, route.Hops[i].ChannelID)
}
}
for i := 0; i < expectedHopCount-1; i++ {
nextChan, ok := route.nextHopChannel(aliases[expectedHops[i].alias])
if !ok {
t.Fatalf("hop didn't have prev chan but should have")
}
if nextChan.ChannelID != route.Hops[i+1].ChannelID {
t.Fatalf("incorrect prev chan: expected %v, got %v",
nextChan.ChannelID, route.Hops[i+1].ChannelID)
}
}
// Final hop shouldn't have a next chan
if _, ok := route.nextHopChannel(aliases[expectedHops[lastHopIndex].alias]); ok {
t.Fatalf("incorrect next hop map, no vertexes should " +
"be after sophon")
}
}
func TestPathFindingWithAdditionalEdges(t *testing.T) {

@ -1760,7 +1760,9 @@ func (r *ChannelRouter) sendPayment(payment *LightningPayment,
// Always determine chan id ourselves, because a channel
// update with id may not be available.
failedChanID, err := getFailedChannelID(route, errSource)
failedChanID, err := getFailedChannelID(
route, errVertex,
)
if err != nil {
return preImage, nil, err
}
@ -1966,28 +1968,40 @@ func (r *ChannelRouter) sendPayment(payment *LightningPayment,
// getFailedChannelID tries to locate the failing channel given a route and the
// pubkey of the node that sent the error. It will assume that the error is
// associated with the outgoing channel of the error node.
func getFailedChannelID(route *Route, errSource *btcec.PublicKey) (
func getFailedChannelID(route *Route, errSource Vertex) (
uint64, error) {
// As this error indicates that the target channel was unable to carry
// this HTLC (for w/e reason), we'll query the index to find the
// _outgoing_ channel the source of the error was meant to pass the
// HTLC along to.
if badChan, ok := route.nextHopChannel(errSource); ok {
return badChan.ChannelID, nil
// If the error originates from ourselves, report our outgoing channel
// as failing.
if errSource == route.SourcePubKey {
return route.Hops[0].ChannelID, nil
}
// If we weren't able to find the hop *after* this node, then we'll
// attempt to disable the previous channel.
//
// TODO(joostjager): errSource must be the final hop then? In that case,
// certain types of errors are not expected. For example
// FailUnknownNextPeer. This could be a reason to prune the node?
if prevChan, ok := route.prevHopChannel(errSource); ok {
return prevChan.ChannelID, nil
hopCount := len(route.Hops)
for i, hop := range route.Hops {
if errSource != hop.PubKeyBytes {
continue
}
// If the errSource is the final hop, we assume that the
// failing channel is the incoming channel.
//
// TODO(joostjager): In this case, certain types of
// errors are not expected. For example
// FailUnknownNextPeer. This could be a reason to prune
// the node?
if i == hopCount-1 {
return route.Hops[i].ChannelID, nil
}
// As this error indicates that the target channel was
// unable to carry this HTLC (for w/e reason), we'll
// query return the _outgoing_ channel that the source
// of the error was meant to pass the HTLC along to.
return route.Hops[i+1].ChannelID, nil
}
return 0, fmt.Errorf("cannot find channel in route")
return 0, fmt.Errorf("cannot find error source node in route")
}
// applyChannelUpdate validates a channel update and if valid, applies it to the