f Check on-chain wallet before we try to open chan

Author: tnull

src/error.rs

@@ -1,6 +1,6 @@
 use std::fmt;
 
-#[derive(Debug)]
+#[derive(Debug, PartialEq, Eq)]
 /// An error that possibly needs to be handled by the user.
 pub enum Error {
 	/// Returned when trying to start [`crate::Node`] while it is already running.
@@ -17,6 +17,8 @@ pub enum Error {
 	InvoiceInvalid,
 	/// Invoice creation failed.
 	InvoiceCreationFailed,
+	/// There are insufficient funds to complete the given operation.
+	FundsInsufficient,
 	/// An attempted payment has failed.
 	PaymentFailed,
 	/// A given peer info could not be parsed.
@@ -47,6 +49,9 @@ impl fmt::Display for Error {
 			Self::NonUniquePaymentHash => write!(f, "An invoice must not get payed twice."),
 			Self::InvoiceInvalid => write!(f, "The given invoice is invalid."),
 			Self::InvoiceCreationFailed => write!(f, "Failed to create invoice."),
+			Self::FundsInsufficient => {
+				write!(f, "There are insufficient funds to complete the given operation.")
+			}
 			Self::PaymentFailed => write!(f, "Failed to send the given payment."),
 			Self::PeerInfoParseFailed => write!(f, "Failed to parse the given peer information."),
 			Self::ChannelCreationFailed => write!(f, "Failed to create channel."),

src/lib.rs

@@ -719,6 +719,12 @@ impl Node {
 
 		let runtime = runtime_lock.as_ref().unwrap();
 
+		let cur_balance = self.wallet.get_balance()?;
+		if cur_balance.get_spendable() < channel_amount_sats {
+			log_error!(self.logger, "Unable to create channel due to insufficient funds.");
+			return Err(Error::FundsInsufficient);
+		}
+
 		let peer_info = PeerInfo::try_from(node_pubkey_and_address.to_string())?;
 
 		let con_peer_info = peer_info.clone();

src/tests/functional_tests.rs

@@ -1,5 +1,5 @@
 use crate::tests::test_utils::expect_event;
-use crate::{Builder, Config, Event};
+use crate::{Builder, Config, Error, Event};
 
 use bitcoin::{Address, Amount};
 use bitcoind::bitcoincore_rpc::RpcApi;
@@ -88,14 +88,16 @@ where
 fn premine_and_distribute_funds(addrs: Vec<Address>, amount: Amount) {
 	PREMINE.get_or_init(|| {
 		generate_blocks_and_wait(101);
-		for addr in addrs {
-			get_bitcoind()
-				.client
-				.send_to_address(&addr, amount, None, None, None, None, None, None)
-				.unwrap();
-		}
-		generate_blocks_and_wait(1);
 	});
+
+	for addr in addrs {
+		get_bitcoind()
+			.client
+			.send_to_address(&addr, amount, None, None, None, None, None, None)
+			.unwrap();
+	}
+
+	generate_blocks_and_wait(1);
 }
 
 fn rand_config() -> Config {
@@ -199,3 +201,32 @@ fn channel_full_cycle() {
 	node_b.stop().unwrap();
 	println!("\nB stopped");
 }
+
+#[test]
+fn channel_open_fails_when_funds_insufficient() {
+	println!("== Node A ==");
+	let config_a = rand_config();
+	let node_a = Builder::from_config(config_a).build();
+	node_a.start().unwrap();
+	let addr_a = node_a.new_funding_address().unwrap();
+
+	println!("\n== Node B ==");
+	let config_b = rand_config();
+	let node_b = Builder::from_config(config_b).build();
+	node_b.start().unwrap();
+	let addr_b = node_b.new_funding_address().unwrap();
+
+	premine_and_distribute_funds(vec![addr_a, addr_b], Amount::from_sat(100000));
+	node_a.sync_wallets().unwrap();
+	node_b.sync_wallets().unwrap();
+	assert_eq!(node_a.on_chain_balance().unwrap().get_spendable(), 100000);
+	assert_eq!(node_b.on_chain_balance().unwrap().get_spendable(), 100000);
+
+	println!("\nA -- connect_open_channel -> B");
+	let node_b_addr =
+		format!("{}@{}", node_b.node_id().unwrap(), node_b.listening_address().unwrap());
+	assert_eq!(
+		Err(Error::FundsInsufficient),
+		node_a.connect_open_channel(&node_b_addr, 120000, true)
+	);
+}