List usable channels

Author: Jasonvdb

example/App.tsx

@@ -125,6 +125,32 @@ const App = () => {
             }}
           />
 
+          <Button
+            title={'List usable channels'}
+            onPress={async () => {
+              try {
+                const res = await ldk.listUsableChannels();
+
+                if (res.isErr()) {
+                  setMessage(res.error.message);
+                  return;
+                }
+
+                let msg = '';
+                res.value.forEach((channel) => {
+                  Object.keys(channel).forEach((key) => {
+                    // @ts-ignore
+                    msg += `${key}: ${channel[key]}\n`;
+                  });
+                });
+
+                setMessage(msg);
+              } catch (e) {
+                setMessage(e.toString());
+              }
+            }}
+          />
+
           <Button
             title={'Pay invoice'}
             onPress={async () => {

ios/Helpers.swift

@@ -45,6 +45,32 @@ extension Invoice {
     }
 }
 
+extension ChannelDetails {
+    var asJson: Any {
+        return [
+            "channel_id": Data(self.get_channel_id()).hexEncodedString(),
+            "is_public": self.get_is_public(),
+            "is_usable": self.get_is_usable(),
+            "is_outbound": self.get_is_outbound(),
+            "balance_msat": self.get_balance_msat(),
+            "counterparty": Data(self.get_counterparty().write()).hexEncodedString(),
+            "funding_txo": Data(self.get_funding_txo()?.write() ?? []).hexEncodedString(),
+            "channel_type": Data(self.get_channel_type().write()).hexEncodedString(),
+            "user_channel_id": self.get_user_channel_id(), //Number
+            "confirmations_required": self.get_confirmations_required().getValue() as Any, // Optional number
+            "short_channel_id": self.get_short_channel_id().getValue() as Any, //Optional number
+            "is_funding_locked": self.get_is_funding_locked(), //Bool
+            "inbound_scid_alias": self.get_inbound_scid_alias().getValue() as Any, //Optional number
+            "get_inbound_payment_scid": self.get_inbound_payment_scid().getValue() as Any, //Optional number,
+            "inbound_capacity_msat": self.get_inbound_capacity_msat(),
+            "channel_value_satoshis": self.get_channel_value_satoshis(),
+            "outbound_capacity_msat": self.get_outbound_capacity_msat(),
+            "force_close_spend_delay": self.get_force_close_spend_delay().getValue() as Any, //Optional number
+            "unspendable_punishment_reserve": self.get_unspendable_punishment_reserve().getValue() as Any //Optional number
+        ]
+    }
+}
+
 extension Data {
     struct HexEncodingOptions: OptionSet {
         let rawValue: Int

ios/Ldk.m

@@ -56,6 +56,8 @@ @interface RCT_EXTERN_MODULE(Ldk, NSObject)
                   reject:(RCTPromiseRejectBlock)reject)
 RCT_EXTERN_METHOD(listChannels:(RCTPromiseResolveBlock)resolve
                   reject:(RCTPromiseRejectBlock)reject)
+RCT_EXTERN_METHOD(listUsableChannels:(RCTPromiseResolveBlock)resolve
+                  reject:(RCTPromiseRejectBlock)reject)
 
 //MARK: Payments
 RCT_EXTERN_METHOD(decode:(NSString *)paymentRequest

ios/Ldk.swift

@@ -460,27 +460,17 @@ class Ldk: NSObject {
             return handleReject(reject, .init_channel_manager)
         }
 
-        resolve(channelManager.list_channels().map { [
-            "channel_id": Data($0.get_channel_id()).hexEncodedString(),
-            "is_public": $0.get_is_public(),
-            "is_usable": $0.get_is_usable(),
-            "is_outbound": $0.get_is_outbound(),
-            "balance_msat": $0.get_balance_msat(),
-            "counterparty": Data($0.get_counterparty().write()).hexEncodedString(),
-            "funding_txo": Data($0.get_funding_txo()?.write() ?? []).hexEncodedString(),
-            "channel_type": Data($0.get_channel_type().write()).hexEncodedString(),
-            "user_channel_id": $0.get_user_channel_id(), //Number
-            "confirmations_required": $0.get_confirmations_required().getValue() as Any, // Optional number
-            "short_channel_id": $0.get_short_channel_id().getValue() as Any, //Optional number
-            "is_funding_locked": $0.get_is_funding_locked(), //Bool
-            "inbound_scid_alias": $0.get_inbound_scid_alias().getValue() as Any, //Optional number
-            "get_inbound_payment_scid": $0.get_inbound_payment_scid().getValue() as Any, //Optional number,
-            "inbound_capacity_msat": $0.get_inbound_capacity_msat(),
-            "channel_value_satoshis": $0.get_channel_value_satoshis(),
-            "outbound_capacity_msat": $0.get_outbound_capacity_msat(),
-            "force_close_spend_delay": $0.get_force_close_spend_delay().getValue() as Any, //Optional number
-            "unspendable_punishment_reserve": $0.get_unspendable_punishment_reserve().getValue() as Any //Optional number
-        ] })
+        resolve(channelManager.list_channels().map { $0.asJson })
+    }
+    
+    @objc
+    func listUsableChannels(_ resolve: @escaping RCTPromiseResolveBlock, reject: @escaping RCTPromiseRejectBlock) {
+        //Sync ChannelMonitors and ChannelManager to chain tip
+        guard let channelManager = channelManager else {
+            return handleReject(reject, .init_channel_manager)
+        }
+                
+        resolve(channelManager.list_usable_channels().map { $0.asJson })
     }
 }
 

src/ldk.ts

@@ -324,6 +324,20 @@ class LDK {
 		}
 	}
 
+	/**
+	 * Returns array of usable channels
+	 * https://docs.rs/lightning/latest/lightning/ln/channelmanager/struct.ChannelDetails.html
+	 * @returns {Promise<Ok<Ok<TChannel[]> | Err<TChannel[]>> | Err<unknown>>}
+	 */
+	async listUsableChannels(): Promise<Result<TChannel[]>> {
+		try {
+			const res = await NativeLDK.listUsableChannels();
+			return ok(res);
+		} catch (e) {
+			return err(e);
+		}
+	}
+
 	/**
 	 * Callback passed though will get triggered for each LND log item
 	 * @param callback