Expose ChannelDetails::channel_shutdown_state

Add a `ChannelShutdownState` enum mirroring LDK's own type, and expose
it as an `Option<ChannelShutdownState>` field on `ChannelDetails`.

Author: f3r10

src/ffi/types.rs

@@ -25,6 +25,7 @@ pub use bitcoin::{Address, BlockHash, FeeRate, Network, OutPoint, ScriptBuf, Txi
 pub use lightning::chain::channelmonitor::BalanceSource;
 use lightning::events::PaidBolt12Invoice as LdkPaidBolt12Invoice;
 pub use lightning::events::{ClosureReason, PaymentFailureReason};
+use lightning::ln::channel_state::ChannelShutdownState;
 use lightning::ln::channelmanager::PaymentId;
 use lightning::ln::msgs::DecodeError;
 pub use lightning::ln::types::ChannelId;
@@ -1408,6 +1409,26 @@ uniffi::custom_type!(LSPSDateTime, String, {
 	},
 });
 
+/// The shutdown state of a channel as returned in [`ChannelDetails::channel_shutdown_state`].
+///
+/// [`ChannelDetails::channel_shutdown_state`]: crate::ChannelDetails::channel_shutdown_state
+#[uniffi::remote(Enum)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum ChannelShutdownState {
+	/// Channel has not sent or received a shutdown message.
+	NotShuttingDown,
+	/// Local node has sent a shutdown message for this channel.
+	ShutdownInitiated,
+	/// Shutdown message exchanges have concluded and the channels are in the midst of
+	/// resolving all existing open HTLCs before closing can continue.
+	ResolvingHTLCs,
+	/// All HTLCs have been resolved, nodes are currently negotiating channel close onchain fee rates.
+	NegotiatingClosingFee,
+	/// We've successfully negotiated a closing_signed dance. At this point `ChannelManager` is about
+	/// to drop the channel.
+	ShutdownComplete,
+}
+
 /// The reason the channel was closed. See individual variants for more details.
 #[uniffi::remote(Enum)]
 #[derive(Clone, Debug, PartialEq, Eq)]

src/lib.rs

@@ -145,7 +145,8 @@ pub use lightning;
 use lightning::chain::BestBlock;
 use lightning::impl_writeable_tlv_based;
 use lightning::ln::chan_utils::FUNDING_TRANSACTION_WITNESS_WEIGHT;
-use lightning::ln::channel_state::{ChannelDetails as LdkChannelDetails, ChannelShutdownState};
+use lightning::ln::channel_state::ChannelDetails as LdkChannelDetails;
+pub use lightning::ln::channel_state::ChannelShutdownState;
 use lightning::ln::channelmanager::PaymentId;
 use lightning::ln::msgs::SocketAddress;
 use lightning::routing::gossip::NodeAlias;

src/types.rs

@@ -15,7 +15,7 @@ use bitcoin::{OutPoint, ScriptBuf};
 use bitcoin_payment_instructions::onion_message_resolver::LDKOnionMessageDNSSECHrnResolver;
 use lightning::chain::chainmonitor;
 use lightning::impl_writeable_tlv_based;
-use lightning::ln::channel_state::ChannelDetails as LdkChannelDetails;
+use lightning::ln::channel_state::{ChannelDetails as LdkChannelDetails, ChannelShutdownState};
 use lightning::ln::msgs::{RoutingMessageHandler, SocketAddress};
 use lightning::ln::peer_handler::IgnoringMessageHandler;
 use lightning::ln::types::ChannelId;
@@ -529,6 +529,10 @@ pub struct ChannelDetails {
 	pub inbound_htlc_maximum_msat: Option<u64>,
 	/// Set of configurable parameters that affect channel operation.
 	pub config: ChannelConfig,
+	/// The current shutdown state of the channel, if any.
+	///
+	/// Will be `None` for objects serialized with LDK Node v0.1 and earlier.
+	pub channel_shutdown_state: Option<ChannelShutdownState>,
 }
 
 impl From<LdkChannelDetails> for ChannelDetails {
@@ -584,6 +588,7 @@ impl From<LdkChannelDetails> for ChannelDetails {
 			inbound_htlc_maximum_msat: value.inbound_htlc_maximum_msat,
 			// unwrap safety: `config` is only `None` for LDK objects serialized prior to 0.0.109.
 			config: value.config.map(|c| c.into()).unwrap(),
+			channel_shutdown_state: value.channel_shutdown_state,
 		}
 	}
 }

tests/common/mod.rs

@@ -31,8 +31,8 @@ use ldk_node::entropy::{generate_entropy_mnemonic, NodeEntropy};
 use ldk_node::io::sqlite_store::SqliteStore;
 use ldk_node::payment::{PaymentDirection, PaymentKind, PaymentStatus};
 use ldk_node::{
-	Builder, CustomTlvRecord, Event, LightningBalance, Node, NodeError, PendingSweepBalance,
-	UserChannelId,
+	Builder, ChannelShutdownState, CustomTlvRecord, Event, LightningBalance, Node, NodeError,
+	PendingSweepBalance, UserChannelId,
 };
 use lightning::io;
 use lightning::ln::msgs::SocketAddress;
@@ -918,6 +918,12 @@ pub(crate) async fn do_channel_full_cycle<E: ElectrumApi>(
 	let user_channel_id_a = expect_channel_ready_event!(node_a, node_b.node_id());
 	let user_channel_id_b = expect_channel_ready_event!(node_b, node_a.node_id());
 
+	// After channel_ready, no shutdown should be in progress.
+	assert!(node_a.list_channels().iter().all(|c| matches!(
+		c.channel_shutdown_state,
+		None | Some(ChannelShutdownState::NotShuttingDown)
+	)));
+
 	println!("\nB receive");
 	let invoice_amount_1_msat = 2500_000;
 	let invoice_description: Bolt11InvoiceDescription =
@@ -1269,6 +1275,20 @@ pub(crate) async fn do_channel_full_cycle<E: ElectrumApi>(
 		node_a.force_close_channel(&user_channel_id_a, node_b.node_id(), None).unwrap();
 	} else {
 		node_a.close_channel(&user_channel_id_a, node_b.node_id()).unwrap();
+		// The cooperative shutdown may complete before we get to check, but if the channel
+		// is still visible it must already be in a shutdown state.
+		if let Some(channel) =
+			node_a.list_channels().into_iter().find(|c| c.user_channel_id == user_channel_id_a)
+		{
+			assert!(
+				!matches!(
+					channel.channel_shutdown_state,
+					None | Some(ChannelShutdownState::NotShuttingDown)
+				),
+				"Expected shutdown in progress on node_a, got {:?}",
+				channel.channel_shutdown_state,
+			);
+		}
 	}
 
 	expect_event!(node_a, ChannelClosed);