The bindings generation really should support generic bounds other
than Deref::Target in where clauses, but currently does not. To
avoid needing to add support during the current release process,
we simply swap around the arguments to move them to the first <>
instead of the where.
The bindings generation really should support default generic types
in where clauses, but currently does not. To avoid needing to add
support during the current release process, we simply swap around
the arguments to move them to the first <> instead of the where.
in an invoice creation utility. Note that if the error type of `create_inbound_payment` ever
changed, we'd be forced to update the invoice utility's callsite to handle the new error
and replace payment_secret with encrypted metadata
See docs on `inbound_payment::verify` for details
Also add min_value checks to all create_inbound_payment* methods
This finally fixes the bug described in the previous commits where
we retry a payment after its retry count has expired due to early
removal of the payment from the retry count tracking map. A test is
also added which demonstrates the bug in previous versions and
which passes now.
Fixes#1164.
Expand the Score trait with a payment_path_successful function for
scoring successful payment paths. Called by InvoicePayer's EventHandler
implementation when processing PaymentPathSuccessful events. May be used
by Score implementations to revert any channel penalties that were
applied by calls to payment_path_failed.
Ultimately we likely need to wrap the locked `Score` in a struct
that exposes writeable somehow, but because all traits have to be
fully concretized for C bindings we'll still need `Writeable` on
all `Score` in order to expose `Writeable` on the locked score.
Otherwise, we'll only have a `LockedScore` with a `Score` visible
that only has the `Score` methods, never the original type.
In upcoming commits, we'll be making the payment secret and payment hash/preimage
derivable from info about the payment + a node secret. This means we don't
need to store any info about incoming payments and can eventually get rid of the
channelmanager::pending_inbound_payments map.
Traits in top-level modules is somewhat confusing - generally
top-level modules are just organizational modules and don't contain
things themselves, instead placing traits and structs in
sub-modules. Further, its incredibly awkward to have a `scorer`
sub-module, but only have a single struct in it, with the relevant
trait it is the only implementation of somewhere else. Not having
`Score` in the `scorer` sub-module is further confusing because
it's the only module anywhere that references scoring at all.
This should allow `Score` implementations to make substantially
better decisions, including of the form "willing to pay X to avoid
routing over this channel which may have a high failure rate".
Implementations of Router may need the payment hash in order to look up
pre-computed routes from a probe for a given payment. Add a PaymentHash
parameter to Router::find_route to allow for this.
Modify all InvoicePayer unit tests to use expect_send instead of
expect_value_msat, since the former can discern whether the send was for
an invoice, spontaneous payment, or a retry. Updates tests to set payer
expectations if they weren't already and assert these before returning a
failure.
InvoicePayer handles retries not only when handling PaymentPathFailed
events but also for some types of PaymentSendFailure on the initial
send. Expand InvoicePayer's interface with a pay_pubkey function for
spontaneous (keysend) payments. Add a send_spontaneous_payment function
to the Payer trait to support this and implement it for ChannelManager.
To support spontaneous payments, InvoicePayer's sending logic must be
invoice-agnostic. Refactor InvoicePayer::pay_invoice_internal such that
invoice-specific code is in pay_invoice_using_amount and the remaining
logic is in pay_internal.
Further refactor the code's payment_cache locking such that it is
accessed consistently when needed, and tidy up the code a bit.
The bindings don't currently support passing `Vec`s of objects
which it mappes as "opaque types". This is because it will require
clones to convert its own list of references to Rust's list of
objects.
In the near future we should resolve this limitation, allowing us
to revert this (and make `find_route`'s method signature similarly
cleaner), but for now we must avoid `Vec<OpaqueType>`.
Scorer uses time to determine how much to penalize a channel after a
failure occurs. Parameterizing it by time cleans up the code such that
no-std support is in a single AlwaysPresent struct, which implements the
Time trait. Time is implemented for std::time::Instant when std is
available.
This parameterization also allows for deterministic testing since a
clock could be devised to advance forward as needed.
This rewrites a good chunk of the retry logic in `InvoicePayer` to
address two issues:
* it was not considering the return value of `send_payment` (and
`retry_payment`) may indicate a failure on some paths but not
others,
* it was not considering that more failures may still come later
when removing elements from the retry count map. This could
result in us seeing an MPP-partial-failure, failing to retry,
removing the retries count entry, and then retrying other parts,
potentially forever.
Users can provide anything they want as `RouteParameters` so we
shouldn't assume any fields are set any particular way, including
`expiry_time` set at all.
As payments fail, the channel responsible for the failure may be
penalized. Implement Scorer::payment_path_failed to penalize the failed
channel using a configured penalty. As time passes, the penalty is
reduced using exponential decay, though penalties will accumulate if the
channel continues to fail. The decay interval is also configurable.
Upon receiving a PaymentPathFailed event, the failing payment may be
retried on a different path. To avoid using the channel responsible for
the failure, a scorer should be notified of the failure before being
used to find a new route.
Add a payment_path_failed method to routing::Score and call it in
InvoicePayer's event handler. Introduce a LockableScore parameterization
to InvoicePayer so the scorer is locked only once before calling
find_route.
According to BOLT 11:
- after the `timestamp` plus `expiry` has passed
- SHOULD NOT attempt a payment
Add a convenience method for checking if an Invoice has expired, and use
it to short-circuit payment retries.
When a payment fails, it's useful to retry the payment once the network
graph and channel scores are updated. InvoicePayer is a utility for
making payments which will retry any failed payment paths for a payment
up to a configured number of total attempts. It is parameterized by a
Payer and Router for ease of customization and testing.
Implement EventHandler for InvoicePayer as a decorator that intercepts
PaymentPathFailed events and retries that payment using the parameters
from the event. It delegates to the decorated EventHandler after retries
have been exhausted and for other events.
An upcoming Router interface will be used for finding a Route both when
initially sending a payment and also when retrying failed payment paths.
Unify the three varieties of get_route so the interface can consist of a
single method implemented by the new `find_route` method. Give get_route
pub(crate) visibility so it can still be used in tests.
InvoiceBuilder's interface was changed recently to work in terms of
msats. Update Invoice's interface to return the amount in msats, too,
and make amount_pico_btc private.
A payee can be identified by a pubkey and optionally have an associated
set of invoice features and route hints. Use this in get_route instead
of three separate parameters. This may be included in PaymentPathFailed
later to use when finding a new route.
Failed payments may be retried, but calling get_route may return a Route
with the same failing path. Add a routing::Score trait used to
parameterize get_route, which it calls to determine how much a channel
should be penalized in terms of msats willing to pay to avoid the
channel.
Also, add a Scorer struct that implements routing::Score with a constant
constant penalty. Subsequent changes will allow for more robust scoring
by feeding back payment path success and failure to the scorer via event
handling.
Now that NetworkGraph uses interior mutability, the RwLock used around
it in NetGraphMsgHandler is no longer needed. This allows for shared
ownership without a lock.