We might be trying to send an invoice amount that's greater than the size of the channel, but once you factor in the custom channel logic, an actual HTLC can be sent over the channel to pay that larger payment.
As a result, we'll skip over this check if a have a custom HTLC.
In preparation for structs outside of the `routing` package implementing
this interface, export `routingGraph` and rename it to `Graph` so as to
avoid stuttering.
Later on in this series, we will need to know during path finding if an
edge we are traversing was derived from a blinded payment path. In
preparation for that, we add a BlindedPayment member to the
`unifiedEdge` struct.
The reason we will need this later on is because: In the case where we
receive multiple blinded paths from the receipient, we will first swap
out the final hop node of each path with a single unified target node so
that path finding can work as normal. Once we have selected a route
though, we will want to know which path an edge belongs to so that we
can swap the correct destination node back in.
Add a constructor for unified edge. In upcoming commits, we will add a
new member to unifiedEdge and a constructor forces us to not forget to
populate a required member.
In the previous commit the AdditionalEdge interface was introduced
with both of its implementations `BlindedEdge` and `PrivateEdge`.
In both cases where we append a route either by a blinded route
section or private route hints we now use these new types. In
addition the `PayloadSizeFunc` type is introduced in the
`unifiedEdge` struct. This is necessary to have the payload size
function at hand when searching for a route hence not overshooting
the max sphinx package size of 1300 bytes.
Having a capacity available is important for liquidity estimation.
* We add a dummy capacity to hop hints. Hop hints specify neither the
capacity nor a maxHTLC size, which is why we assume the channel to
have a high capacity relative to the amount we send.
* We add a capacity to local edges. These channels should always have a
capacity associated with them, even in the neutrino case (a fallback
to maxHTLC is not necessary). This is just for completeness, as the
probability calculation for local channels is done separately.
This commit adds the maximal capacity between two nodes to the unified
edge data. We use MaxHTLC as a replacement if the channel capacity is
not available.
In tests we use larger maxHTLC values to be able to convert to a
non-zero sat capacity.
This commit refactors the semantics of unified policies to unified
edges. The main changes are the following renamings:
* unifiedPolicies -> nodeEdgeUnifier
* unifiedPolicy -> edgeUnifier
* unifiedPolicyEdge -> unifiedEdge
Comments and shortened variable names are changed to reflect the new
semantics.
