Currently, users have no means to upper-bound the total fees accruing
when finding a route. Here, we add a corresponding field to
`RouteParameters` which will be used to limit the candidate set during
path finding in the following commits.
We add a `ChannelManager::send_preflight_probes` method that can be used
to send pre-flight probes given some [`RouteParameters`]. Additionally,
we add convenience methods in for spontaneous probes and send pre-flight
probes for a given invoice.
As pre-flight probes might take up some of the available liquidity, we
here introduce that channels whose available liquidity is less than the
required amount times
`UserConfig::preflight_probing_liquidity_limit_multiplier` won't be used
to send pre-flight probes.
This commit is a more or less a carbon copy of the pre-flight
probing code recently added to LDK Node.
Custom TLVs allow users to send extra application-specific data with
a payment. These have the additional flexibility compared to
`payment_metadata` that they don't have to reflect recipient generated
data provided in an invoice, in which `payment_metadata` could be
reused.
We ensure provided type numbers are unique, increasing, and within the
experimental range with the `RecipientOnionFields::with_custom_tlvs`
method.
This begins sender-side support for custom TLVs.
This adds the new `payment_metadata` to `RecipientOnionFields`,
passing the metadata from BOLT11 invoices through the send pipeline
and finally copying them info the onion when sending HTLCs.
This completes send-side support for the new payment metadata
feature.
This moves the public payment sending API from passing an explicit
`PaymentSecret` to a new `RecipientOnionFields` struct (which
currently only contains the `PaymentSecret`). This gives us
substantial additional flexibility as we look at add both
`PaymentMetadata`, a new (well, year-or-two-old) BOLT11 invoice
extension to provide additional data sent to the recipient.
In the future, we should also add the ability to add custom TLV
entries in the `RecipientOnionFields` struct.
fbc08477e8 purported to "move" the
`final_cltv_expiry_delta` field to `PaymentParamters` from
`RouteParameters`. However, for naive backwards-compatibility
reasons it left the existing on in place and only added a new,
redundant field in `PaymentParameters`.
It turns out there's really no reason for this - if we take a more
critical eye towards backwards compatibility we can figure out the
correct value in every `PaymentParameters` while deserializing.
We do this here - making `PaymentParameters` a `ReadableArgs`
taking a "default" `cltv_expiry_delta` when it goes to read. This
allows existing `RouteParameters` objects to pass the read
`final_cltv_expiry_delta` field in to be used if the new field
wasn't present.
Prior to this, we returned PaymentSendFailure from auto retry send payment
methods. This implied that we might return a PartialFailure from them, which
has never been the case. So it makes sense to rework the errors to be a better
fit for the methods.
We're taking error handling in a totally different direction now to make it
more asynchronous, see send_payment_internal for more information.
`PaymentParams` is all about the parameters for a payment, i.e. the
parameters which are static across all the paths of a paymet.
`RouteParameters` is about the information specific to a given
`Route` (i.e. a set of paths, among multiple potential sets of
paths for a payment). The CLTV delta thus doesn't belong in
`RouterParameters` but instead in `PaymentParameters`.
Worse, because `RouteParameters` is built from the information in
the last hops of a `Route`, when we deliberately inflate the CLTV
delta in path-finding, retries of the payment will have the final
CLTV delta double-inflated as it inflates starting from the final
CLTV delta used in the last attempt.
By moving the CLTV delta to `PaymentParameters` we avoid this
issue, leaving only the sought amount in the `RouteParameters`.
All utility functions for invoice construction will now also accept an
Option<>al `min_final_cltv_expiry_delta` which is useful for things like
swaps etc. The `min_final_cltv_expiry_delta` will default back to
`MIN_FINAL_CLTV_EXPIRY_DELTA` if `None` is provided.
This matches the spec and helps avoid any confusion around
naming. We're also then consistent with `cltv_expiry` in an HTLC being
the actual block height value for the CLTV and not a delta.
As of HEAD the `ChannelManager` is parametrized by a `Router`, while
`InvoicePayer` also owns a `Router`. In order to allow for a single
object being reused, we make the `InvoicePayer` side `Deref`.
This is purely a refactor that does not change the InitFeatures
advertised by a ChannelManager. This allows users to configure which
features should be advertised based on the values of `UserConfig`. While
there aren't any existing features currently leveraging this behavior,
it will be used by the upcoming anchors_zero_fee_htlc_tx feature.
The UserConfig dependency on provided_init_features caused most
callsites of the main test methods responsible for opening channels to
be updated. This commit foregos that completely by no longer requiring
the InitFeatures of each side to be provided to these methods. The
methods already require a reference to each node's ChannelManager to
open the channel, so we use that same reference to obtain their
InitFeatures. A way to override such features was required for some
tests, so a new `override_init_features` config option now exists on
the test harness.
`ScorerAccountingForInFlightHtlcs` generally stores a `Score`
reference generated by calling `LockableScore::lock`, which
actually returns an arbitrary `Score`. Given `Score` is implemented
directly on lock types, it makes sense to simply hold a fully owned
`Score` in `ScorerAccountingForInFlightHtlcs` rather than a mutable
reference to one.
In c70bd1f, we implemented tracking HTLCs by adding path information
for pending HTLCs to `InvoicePayer`’s `payment_cache` when receiving
specific events.
Since we can now track inflight HTLCs entirely within ChannelManager,
there is no longer a need for this to exist.
We introduce a new sealed trait BaseEventHandler that has a blanket
implementation for any T. Since the trait cannot be implemented outside
of the crate, this allow us to expose specific implementations of
InvoicePayer that allow for synchronous and asynchronous event handling.
When a user attempts to send a payment but it fails due to
idempotency key violation, they need to know that this was the
reason as they need to handle the error programmatically
differently from other errors.
Here we simply add a new `PaymentSendFailure` enum variant for
`DuplicatePayment` to allow for that.
It was pointed out that its quite confusing that
`AllFailedRetrySafe` does not allow you to call `retry_payment`,
though the documentation on it does specify this. Instead, we
simply rename it to `AllFailedResendSafe` to indicate that the
action that is safe to take is *resending*, not *retrying*.
This is part of moving the Router trait into ChannelManager, which will help
allow ChannelManager to fetch routes on-the-fly as part of supporting
trampoline payments.
In order to allow users to pass a custom idempotency key to the
`send*` methods in `InvoicePayer`, we have to pipe the `PaymentId`
through to the `Payer` methods, which we do here.
By default, existing `InvoicePayer` methods use the `PaymentHash`
as the `PaymentId`, however we also add duplicate `send*_with_id`
methods which allow users to pass a custom `PaymentId`.
Finally, appropriate documentation updates are made to clarify
idempotency guarantees.
`hashbrown` depends on `ahash` which depends on `once_cell`. Sadly,
in https://github.com/matklad/once_cell/issues/201 the `once_cell`
maintainer decided they didn't want to do the work of having an
MSRV policy for `once_cell`, making `ahash`, and thus `hashbrown`
require the latest compiler. I've reached out to `ahash` to suggest
they drop the dependency (as they could trivially work around not
having it), but until then we simply downgrade `hashbrown`.
`rust-bitcoin` also requires an older `hashbrown` so we're actually
reducing our total `no-std` code here anyway.