Add new ConfirmationTarget variant for min mempool feerates

[rust-lightning] / lightning / src / chain / chaininterface.rs

diff --git a/lightning/src/chain/chaininterface.rs b/lightning/src/chain/chaininterface.rs
index 1a446249105c8772ead4b9f1c1167d3ea160219a..4204d714f1b12be5a7a1a04fed5092746562c827 100644 (file)
--- a/lightning/src/chain/chaininterface.rs
+++ b/lightning/src/chain/chaininterface.rs
@@ -19,19 +19,40 @@ use bitcoin::blockdata::transaction::Transaction;
 
 /// An interface to send a transaction to the Bitcoin network.
 pub trait BroadcasterInterface {
-       /// Sends a transaction out to (hopefully) be mined.
-       fn broadcast_transaction(&self, tx: &Transaction);
+       /// Sends a list of transactions out to (hopefully) be mined.
+       /// This only needs to handle the actual broadcasting of transactions, LDK will automatically
+       /// rebroadcast transactions that haven't made it into a block.
+       ///
+       /// In some cases LDK may attempt to broadcast a transaction which double-spends another
+       /// and this isn't a bug and can be safely ignored.
+       ///
+       /// If more than one transaction is given, these transactions should be considered to be a
+       /// package and broadcast together. Some of the transactions may or may not depend on each other,
+       /// be sure to manage both cases correctly.
+       ///
+       /// Bitcoin transaction packages are defined in BIP 331 and here:
+       /// https://github.com/bitcoin/bitcoin/blob/master/doc/policy/packages.md
+       fn broadcast_transactions(&self, txs: &[&Transaction]);
 }
 
-/// An enum that represents the speed at which we want a transaction to confirm used for feerate
+/// An enum that represents the priority at which we want a transaction to confirm used for feerate
 /// estimation.
-#[derive(Clone, Copy, Hash, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, Hash, PartialEq, Eq)]
 pub enum ConfirmationTarget {
-       /// We are happy with this transaction confirming slowly when feerate drops some.
+       /// We'd like a transaction to confirm in the future, but don't want to commit most of the fees
+       /// required to do so yet. The remaining fees will come via a Child-Pays-For-Parent (CPFP) fee
+       /// bump of the transaction.
+       ///
+       /// The feerate returned should be the absolute minimum feerate required to enter most node
+       /// mempools across the network. Note that if you are not able to obtain this feerate estimate,
+       /// you should likely use the furthest-out estimate allowed by your fee estimator.
+       MempoolMinimum,
+       /// We are happy with a transaction confirming slowly, at least within a day or so worth of
+       /// blocks.
        Background,
-       /// We'd like this transaction to confirm without major delay, but 12-18 blocks is fine.
+       /// We'd like a transaction to confirm without major delayed, i.e., within the next 12-24 blocks.
        Normal,
-       /// We'd like this transaction to confirm in the next few blocks.
+       /// We'd like a transaction to confirm in the next few blocks.
        HighPriority,
 }