0.0.104

API Updates

• A PaymentFailed event is now provided to indicate a payment has failed
  fully. This event is generated either after
  ChannelManager::abandon_payment is called for a given payment, or the
  payment times out, and there are no further pending HTLCs for the payment.
  This event should be used to detect payment failure instead of
  PaymentPathFailed::all_paths_failed, unless no payment retries occur via
  ChannelManager::retry_payment (#1202).
• Payment secrets are now generated deterministically using material from
  the new KeysInterface::get_inbound_payment_key_material (#1177).
• A PaymentPathSuccessful event has been added to ease passing success info
  to a scorer, along with a Score::payment_path_successful method to accept
  such info (#1178, #1197).
• Score::channel_penalty_msat has additional arguments describing the
  channel's capacity and the HTLC amount being sent over the channel (#1166).
• A new log level Gossip has been added, which is used for verbose
  information generated during network graph sync. Enabling the
  max_level_trace feature or ignoring Gossip log entries reduces log
  growth during initial start up from many GiB to several MiB (#1145).
• The allow_wallclock_use feature has been removed in favor of only using
  the std and no-std features (#1212).
• NetworkGraph can now remove channels that we haven't heard updates for in
  two weeks with NetworkGraph::remove_stale_channels{,with_time}. The first
  is called automatically if a NetGraphMsgHandler is passed to
  BackgroundProcessor::start (#1212).
• InvoicePayer::pay_pubkey was added to enable sending "keysend" payments to
  supported recipients, using the InvoicePayer to handle retires (#1160).
• user_payment_id has been removed from PaymentPurpose, and
  ChannelManager::create_inbound_payment{,_for_hash} (#1180).
• Updated documentation for several ChannelManager functions to remove stale
  references to panics which no longer occur (#1201).
• The Score and LockableScore objects have moved into the
  routing::scoring module instead of being in the routing module (#1166).
• The Time parameter to ScorerWithTime is no longer longer exposed,
  instead being fixed based on the std/no-std feature (#1184).
• ChannelDetails::balance_msat was added to fetch a channel's balance
  without subtracting the reserve values, lining up with on-chain claim amounts
  less on-chain fees (#1203).
• An explicit UserConfig::accept_inbound_channels flag is now provided,
  removing the need to set min_funding_satoshis to > 21 million BTC (#1173).
• Inbound channels that fail to see the funding transaction confirm within
  2016 blocks are automatically force-closed with
  ClosureReason::FundingTimedOut (#1083).
• We now accept a channel_reserve value of 0 from counterparties, as it is
  insecure for our counterparty but not us (#1163).
• NetAddress::OnionV2 parsing was removed as version 2 onion services are no
  longer supported in modern Tor (#1204).
• Generation and signing of anchor outputs is now supported in the
  KeysInterface, though no support for them exists in the channel itself (#1176)

Bug Fixes

• Fixed a race condition in InvoicePayer where paths may be retried after
  the retry count has been exceeded. In this case the
  Event::PaymentPathFailed::all_paths_failed field is not a reliable payment
  failure indicator. There was no acceptable alternative indicator,
  Event::PaymentFailed as been added to provide one (#1202).
• Reduced the blocks-before-timeout we expect of outgoing HTLCs before
  refusing to forward. This check was overly strict and resulted in refusing
  to forward som HTLCs to a next hop that had a lower security threshold than
  us (#1119).
• LDK no longer attempt to update the channel fee for outbound channels when
  we cannot afford the new fee. This could have caused force-closure by our
  channel counterparty (#1054).
• Fixed several bugs which may have prevented the reliable broadcast of our
  own channel announcements and updates (#1169).
• Fixed a rare bug which may have resulted in spurious route finding failures
  when using last-hop hints and MPP with large value payments (#1168).
• KeysManager::spend_spendable_outputs no longer adds a change output that
  is below the dust threshold for non-standard change scripts (#1131).
• Fixed a minor memory leak when attempting to send a payment that fails due
  to an error when updating the ChannelMonitor (#1143).
• Fixed a bug where a FeeEstimator that returns values rounded to the next
  sat/vbyte may result in force-closures (#1208).
• Handle MPP timeout HTLC error codes, instead of considering the recipient to
  have sent an invalid error, removing them from the network graph (#1148)

Serialization Compatibility

• All above new events/fields are ignored by prior clients. All above new
  events/fields are not present when reading objects serialized by prior
  versions of the library.
• Payment secrets are now generated deterministically. This reduces the memory
  footprint for inbound payments, however, newly-generated inbound payments
  using ChannelManager::create_inbound_payment{,_for_hash} will not be
  receivable using versions prior to 0.0.104.
  ChannelManager::create_inbound_payment{,_for_hash}_legacy are provided for
  backwards compatibility (#1177).
• PaymentPurpose::InvoicePayment::user_payment_id will be 0 when reading
  objects written with 0.0.104 when read by 0.0.103 and previous (#1180).

In total, this release features 51 files changed, 5356 insertions, 2238
deletions in 107 commits from 9 authors, in alphabetical order:

• Antoine Riard
• Conor Okus
• Devrandom
• Duncan Dean
• Elias Rohrer
• Jeffrey Czyz
• Ken Sedgwick
• Matt Corallo
• Valentine Wallace