We introduce the `ChannelPhase` enum which will contain the different
channel structs wrapped by each of its variants so that we can place
these within a single `channel_by_id` map in `peer_state` in the
following commits. This will reduce the number of map lookup operations
we need to do in `ChannelManager`'s various methods. It will also make
certain channel counting logic easier to reason about with less risk of
forgetting to modify logic when new channels structs are introduced for
V2 channel establishment.
Replace a constant three retry attempts for BOLT 12 invoice payments
with a retry strategy specified when creating a pending outbound
payment. This is configured by users in a later commit when constructing
an InvoiceRequest or a Refund.
An upcoming commit requires serializing Retry, so use a type with a
fixed byte length. Otherwise, using eight bytes to serialize a usize
would fail to read on 32-bit machines.
Add a send_payment_for_bolt12_invoice method to OutboundPayments for
initiating payment of a BOLT 12 invoice. This will be called from an
OffersMessageHandler, after which any retries are handled using the
Retryable logic.
Consolidate the creation and insertion of onion_session_privs to the
PendingOutboundPayment::Retryable arm. In an upcoming commit, this
method will be reused for an initial BOLT 12 invoice payment. However,
onion_session_privs are created using a different helper.
When a BOLT 12 invoice has been received, a payment attempt is made and
any errors result in abandoning the PendingOutboundPayment. This results
in generating at PaymentFailed event, which has a PaymentHash. Thus,
when receiving an invoice, transition from AwaitingInvoice to a new
InvoiceReceived state, the latter of which contains a PaymentHash such
the abandon_payment helper can still be used.
When a BOLT 12 invoice has been requested, in order to guarantee
invoice payment idempotency the future payment needs to be tracked. Add
an AwaitingInvoice variant to PendingOutboundPayment such that only
requested invoices are paid only once. Timeout after a few timer ticks
if a request has not been received.
Firstly, we switch our BP over to use `FilesystemStore`, which also gives us test
coverage and ensures the compatibility.
Then, we remove the superseded `KVStorePersister` trait and
the `FilesystemPersister` code.
We upstream the `KVStore` interface trait from LDK Node, which will
replace `KVStorePersister` in the coming commits.
Besides persistence, `KVStore` implementations will also offer to `list`
keys present in a given `namespace` and `read` the stored values.
When an invoice is requested but either receives an error or never
receives a response, surface an event to indicate to the user that the
corresponding future payment has failed.
