feat(lnd): closed-channels RPC, closing channels in list, streaming close with txid

- lnd.closedchannels: closed-channel history via /v1/channels/closed
- channel list now includes waiting-close and force-closing pending
  channels with their closing_txid
- closechannel reads the close stream's first update with a dedicated
  client instead of hanging until the closing tx confirms; returns the
  closing txid in display byte order

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

core/archipelago/src/api/rpc/dispatcher.rs

@@ -124,6 +124,7 @@ impl RpcHandler {
             }
             "lnd.getinfo" => self.handle_lnd_getinfo().await,
             "lnd.listchannels" => self.handle_lnd_listchannels().await,
+            "lnd.closedchannels" => self.handle_lnd_closedchannels().await,
             "lnd.openchannel" => self.handle_lnd_openchannel(params).await,
             "lnd.closechannel" => self.handle_lnd_closechannel(params).await,
             "lnd.newaddress" => self.handle_lnd_newaddress().await,

core/archipelago/src/api/rpc/lnd/channels.rs

@@ -30,6 +30,8 @@ struct ChannelInfo {
     active: bool,
     status: String,
     channel_point: String,
+    #[serde(skip_serializing_if = "String::is_empty")]
+    closing_txid: String,
 }
 
 #[derive(Debug, Serialize)]
@@ -58,6 +60,10 @@ struct LndChannel {
 #[derive(Debug, Deserialize, Default)]
 struct LndPendingChannelsResponse {
     pending_open_channels: Option<Vec<LndPendingOpenChannel>>,
+    // Cooperative closes waiting for their closing tx to confirm
+    waiting_close_channels: Option<Vec<LndWaitingCloseChannel>>,
+    // Force closes serving out their timelock
+    pending_force_closing_channels: Option<Vec<LndForceClosingChannel>>,
 }
 
 #[derive(Debug, Deserialize)]
@@ -65,6 +71,18 @@ struct LndPendingOpenChannel {
     channel: Option<LndPendingChannel>,
 }
 
+#[derive(Debug, Deserialize)]
+struct LndWaitingCloseChannel {
+    channel: Option<LndPendingChannel>,
+    closing_txid: Option<String>,
+}
+
+#[derive(Debug, Deserialize)]
+struct LndForceClosingChannel {
+    channel: Option<LndPendingChannel>,
+    closing_txid: Option<String>,
+}
+
 #[derive(Debug, Deserialize)]
 struct LndPendingChannel {
     remote_node_pub: Option<String>,
@@ -74,6 +92,52 @@ struct LndPendingChannel {
     channel_point: Option<String>,
 }
 
+impl LndPendingChannel {
+    fn into_channel_info(self, status: &str, closing_txid: Option<String>) -> ChannelInfo {
+        let parse = |s: &Option<String>| s.as_deref().and_then(|v| v.parse().ok()).unwrap_or(0);
+        ChannelInfo {
+            chan_id: String::new(),
+            remote_pubkey: self.remote_node_pub.clone().unwrap_or_default(),
+            capacity: parse(&self.capacity),
+            local_balance: parse(&self.local_balance),
+            remote_balance: parse(&self.remote_balance),
+            active: false,
+            status: status.into(),
+            channel_point: self.channel_point.unwrap_or_default(),
+            closing_txid: closing_txid.unwrap_or_default(),
+        }
+    }
+}
+
+#[derive(Debug, Deserialize, Default)]
+struct LndClosedChannelsResponse {
+    channels: Option<Vec<LndClosedChannel>>,
+}
+
+#[derive(Debug, Deserialize)]
+struct LndClosedChannel {
+    chan_id: Option<String>,
+    remote_pubkey: Option<String>,
+    capacity: Option<String>,
+    settled_balance: Option<String>,
+    close_type: Option<String>,
+    closing_tx_hash: Option<String>,
+    channel_point: Option<String>,
+    close_height: Option<i64>,
+}
+
+#[derive(Debug, Serialize)]
+struct ClosedChannelInfo {
+    chan_id: String,
+    remote_pubkey: String,
+    capacity: i64,
+    settled_balance: i64,
+    close_type: String,
+    closing_tx_hash: String,
+    channel_point: String,
+    close_height: i64,
+}
+
 impl RpcHandler {
     pub(in crate::api::rpc) async fn handle_lnd_listchannels(&self) -> Result<serde_json::Value> {
         let (client, macaroon_hex) = self.lnd_client().await?;
@@ -131,6 +195,7 @@ impl RpcHandler {
                         "inactive".into()
                     },
                     channel_point: ch.channel_point.unwrap_or_default(),
+                    closing_txid: String::new(),
                 }
             })
             .collect();
@@ -138,31 +203,17 @@ impl RpcHandler {
         let mut pending_channels: Vec<ChannelInfo> = Vec::new();
         for pch in pending_resp.pending_open_channels.unwrap_or_default() {
             if let Some(ch) = pch.channel {
-                let capacity: i64 = ch
+                pending_channels.push(ch.into_channel_info("pending_open", None));
-                    .capacity
+            }
-                    .as_deref()
+        }
-                    .and_then(|s| s.parse().ok())
+        for wch in pending_resp.waiting_close_channels.unwrap_or_default() {
-                    .unwrap_or(0);
+            if let Some(ch) = wch.channel {
-                let local: i64 = ch
+                pending_channels.push(ch.into_channel_info("closing", wch.closing_txid));
-                    .local_balance
+            }
-                    .as_deref()
+        }
-                    .and_then(|s| s.parse().ok())
+        for fch in pending_resp.pending_force_closing_channels.unwrap_or_default() {
-                    .unwrap_or(0);
+            if let Some(ch) = fch.channel {
-                let remote: i64 = ch
+                pending_channels.push(ch.into_channel_info("force_closing", fch.closing_txid));
-                    .remote_balance
-                    .as_deref()
-                    .and_then(|s| s.parse().ok())
-                    .unwrap_or(0);
-                pending_channels.push(ChannelInfo {
-                    chan_id: String::new(),
-                    remote_pubkey: ch.remote_node_pub.unwrap_or_default(),
-                    capacity,
-                    local_balance: local,
-                    remote_balance: remote,
-                    active: false,
-                    status: "pending_open".into(),
-                    channel_point: ch.channel_point.unwrap_or_default(),
-                });
             }
         }
 
@@ -349,6 +400,46 @@ impl RpcHandler {
         Ok(body)
     }
 
+    pub(in crate::api::rpc) async fn handle_lnd_closedchannels(&self) -> Result<serde_json::Value> {
+        let (client, macaroon_hex) = self.lnd_client().await?;
+
+        let resp: LndClosedChannelsResponse = client
+            .get(format!("{LND_REST_BASE_URL}/v1/channels/closed"))
+            .header("Grpc-Metadata-macaroon", &macaroon_hex)
+            .send()
+            .await
+            .context("LND REST connection failed")?
+            .json()
+            .await
+            .context("Failed to parse LND closed channels response")?;
+
+        let channels: Vec<ClosedChannelInfo> = resp
+            .channels
+            .unwrap_or_default()
+            .into_iter()
+            .map(|ch| ClosedChannelInfo {
+                chan_id: ch.chan_id.unwrap_or_default(),
+                remote_pubkey: ch.remote_pubkey.unwrap_or_default(),
+                capacity: ch
+                    .capacity
+                    .as_deref()
+                    .and_then(|s| s.parse().ok())
+                    .unwrap_or(0),
+                settled_balance: ch
+                    .settled_balance
+                    .as_deref()
+                    .and_then(|s| s.parse().ok())
+                    .unwrap_or(0),
+                close_type: ch.close_type.unwrap_or_default(),
+                closing_tx_hash: ch.closing_tx_hash.unwrap_or_default(),
+                channel_point: ch.channel_point.unwrap_or_default(),
+                close_height: ch.close_height.unwrap_or(0),
+            })
+            .collect();
+
+        Ok(serde_json::json!({ "channels": channels }))
+    }
+
     pub(in crate::api::rpc) async fn handle_lnd_closechannel(
         &self,
         params: Option<serde_json::Value>,
@@ -389,27 +480,35 @@ impl RpcHandler {
             "Closing Lightning channel"
         );
 
-        let (client, macaroon_hex) = self.lnd_client().await?;
+        let (_, macaroon_hex) = self.lnd_client().await?;
+
+        // The close endpoint is server-streaming: LND holds the connection
+        // open and emits updates until the closing tx CONFIRMS on-chain
+        // (potentially hours). Reading the whole body hangs the RPC even
+        // though the close already went through, and the shared lnd_client's
+        // 15s total timeout would abort the stream mid-read. Use a dedicated
+        // client and return as soon as the first streamed update arrives.
+        let client = reqwest::Client::builder()
+            .no_proxy()
+            .connect_timeout(std::time::Duration::from_secs(10))
+            .danger_accept_invalid_certs(true)
+            .build()
+            .context("Failed to create streaming HTTP client")?;
 
         let url = format!(
             "{LND_REST_BASE_URL}/v1/channels/{}/{}?force={}",
             parts[0], parts[1], force
         );
 
-        let resp = client
+        let mut resp = client
             .delete(&url)
             .header("Grpc-Metadata-macaroon", &macaroon_hex)
             .send()
             .await
             .context("Failed to close channel")?;
 
-        let status = resp.status();
+        if !resp.status().is_success() {
-        let body: serde_json::Value = resp
+            let body: serde_json::Value = resp.json().await.unwrap_or_default();
-            .json()
-            .await
-            .context("Failed to parse close channel response")?;
-
-        if !status.is_success() {
             let msg = body
                 .get("message")
                 .and_then(|v| v.as_str())
@@ -417,6 +516,56 @@ impl RpcHandler {
             return Err(anyhow::anyhow!("Failed to close channel: {}", msg));
         }
 
-        Ok(serde_json::json!({ "success": true }))
+        // First streamed line is {"result":{"close_pending":…}} on success or
+        // {"error":…} — the stream reports errors in-band after a 200.
+        let mut buf: Vec<u8> = Vec::new();
+        let first_update = tokio::time::timeout(std::time::Duration::from_secs(25), async {
+            while let Some(chunk) = resp.chunk().await? {
+                buf.extend_from_slice(&chunk);
+                let line = match buf.iter().position(|&b| b == b'\n') {
+                    Some(pos) => &buf[..pos],
+                    None => &buf[..],
+                };
+                if let Ok(v) = serde_json::from_slice::<serde_json::Value>(line) {
+                    return Ok::<_, anyhow::Error>(Some(v));
+                }
+            }
+            Ok(None)
+        })
+        .await;
+
+        match first_update {
+            Ok(Ok(Some(update))) => {
+                if let Some(err) = update.get("error") {
+                    let msg = err
+                        .get("message")
+                        .and_then(|v| v.as_str())
+                        .unwrap_or("Unknown error");
+                    return Err(anyhow::anyhow!("Failed to close channel: {}", msg));
+                }
+                // txid arrives base64-encoded in internal byte order; flip it
+                // into the display order explorers use.
+                use base64::Engine as _;
+                let closing_txid = update
+                    .pointer("/result/close_pending/txid")
+                    .and_then(|v| v.as_str())
+                    .and_then(|b64| base64::engine::general_purpose::STANDARD.decode(b64).ok())
+                    .map(|mut bytes| {
+                        bytes.reverse();
+                        hex::encode(bytes)
+                    })
+                    .unwrap_or_default();
+                info!(channel_point, closing_txid, "Channel close initiated");
+                Ok(serde_json::json!({ "success": true, "closing_txid": closing_txid }))
+            }
+            Ok(Ok(None)) => Err(anyhow::anyhow!(
+                "LND ended the close stream without an update — check the channel list"
+            )),
+            Ok(Err(e)) => Err(e).context("Failed reading close channel response"),
+            // No update inside the window: the close is almost certainly still
+            // negotiating with the peer — report initiated, the channel list
+            // will show it under Closing.
+            Err(_) => Ok(serde_json::json!({ "success": true, "closing_txid": "" })),
+        }
     }
 }