channeldb: add ComputeFee function

This commit is contained in:
Joost Jager 2019-01-24 21:14:05 +01:00
parent 95502da7e8
commit 8c44cf4a22
No known key found for this signature in database
GPG Key ID: A61B9D4C393C59C7
2 changed files with 14 additions and 11 deletions

@ -155,6 +155,9 @@ const (
// would be possible for a node to create a ton of updates and slowly
// fill our disk, and also waste bandwidth due to relaying.
MaxAllowedExtraOpaqueBytes = 10000
// feeRateParts is the total number of parts used to express fee rates.
feeRateParts = 1e6
)
// ChannelGraph is a persistent, on-disk graph representation of the Lightning
@ -2820,6 +2823,15 @@ func (c *ChannelEdgePolicy) IsDisabled() bool {
lnwire.ChanUpdateDisabled
}
// ComputeFee computes the fee to forward an HTLC of `amt` milli-satoshis over
// the passed active payment channel. This value is currently computed as
// specified in BOLT07, but will likely change in the near future.
func (c *ChannelEdgePolicy) ComputeFee(
amt lnwire.MilliSatoshi) lnwire.MilliSatoshi {
return c.FeeBaseMSat + (amt*c.FeeProportionalMillionths)/feeRateParts
}
// FetchChannelEdgesByOutpoint attempts to lookup the two directed edges for
// the channel identified by the funding outpoint. If the channel can't be
// found, then ErrEdgeNotFound is returned. A struct which houses the general

@ -66,15 +66,6 @@ type edgePolicyWithSource struct {
edge *channeldb.ChannelEdgePolicy
}
// computeFee computes the fee to forward an HTLC of `amt` milli-satoshis over
// the passed active payment channel. This value is currently computed as
// specified in BOLT07, but will likely change in the near future.
func computeFee(amt lnwire.MilliSatoshi,
edge *channeldb.ChannelEdgePolicy) lnwire.MilliSatoshi {
return edge.FeeBaseMSat + (amt*edge.FeeProportionalMillionths)/1000000
}
// newRoute returns a fully valid route between the source and target that's
// capable of supporting a payment of `amtToSend` after fees are fully
// computed. If the route is too long, or the selected path cannot support the
@ -129,7 +120,7 @@ func newRoute(amtToSend lnwire.MilliSatoshi, sourceVertex route.Vertex,
// and its policy for the outgoing channel. This policy
// is stored as part of the incoming channel of
// the next hop.
fee = computeFee(amtToForward, pathEdges[i+1])
fee = pathEdges[i+1].ComputeFee(amtToForward)
}
// If this is the last hop, then for verification purposes, the
@ -482,7 +473,7 @@ func findPath(g *graphParams, r *RestrictParams, cfg *PathFindingConfig,
var fee lnwire.MilliSatoshi
var timeLockDelta uint16
if fromVertex != source {
fee = computeFee(amountToSend, edge)
fee = edge.ComputeFee(amountToSend)
timeLockDelta = edge.TimeLockDelta
}