Add Eclair interop test for zero-fee-commitments

Co-Authored-By: HAL 9000

Author: tankyleo

.github/workflows/0fc-integration.yml

@@ -47,3 +47,54 @@ jobs:
       - name: Test with 0FC enabled
         run: |
           RUSTFLAGS="--cfg no_download --cfg cycle_tests --cfg tokio_unstable --cfg zero_fee_commitment_tests" cargo test -- --test-threads=1
+  eclair-interop-test:
+    timeout-minutes: 60
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Start bitcoind and electrs
+        run: docker compose -p ldk-node -f tests/docker/docker-compose-eclair.yml up -d bitcoin electrs
+
+      - name: Wait for bitcoind to be healthy
+        run: |
+          for i in $(seq 1 30); do
+            if docker compose -p ldk-node -f tests/docker/docker-compose-eclair.yml exec bitcoin bitcoin-cli -regtest -rpcuser=user -rpcpassword=pass getblockchaininfo > /dev/null 2>&1; then
+              echo "bitcoind is ready"
+              exit 0
+            fi
+            echo "Waiting for bitcoind... ($i/30)"
+            sleep 2
+          done
+          echo "ERROR: bitcoind not ready"
+          exit 1
+
+      - name: Create wallets on bitcoind
+        run: |
+          docker compose -p ldk-node -f tests/docker/docker-compose-eclair.yml exec bitcoin bitcoin-cli -regtest -rpcuser=user -rpcpassword=pass createwallet eclair
+          docker compose -p ldk-node -f tests/docker/docker-compose-eclair.yml exec bitcoin bitcoin-cli -regtest -rpcuser=user -rpcpassword=pass -rpcwallet=eclair getnewaddress
+          docker compose -p ldk-node -f tests/docker/docker-compose-eclair.yml exec bitcoin bitcoin-cli -regtest -rpcuser=user -rpcpassword=pass createwallet ldk_node_test
+
+      - name: Start Eclair with 0FC enabled
+        env:
+          ECLAIR_EXTRA_JAVA_OPTS: "-Declair.features.zero_fee_commitments=optional"
+        run: docker compose -p ldk-node -f tests/docker/docker-compose-eclair.yml up -d eclair
+
+      - name: Wait for Eclair to be ready
+        run: |
+          for i in $(seq 1 60); do
+            if curl -sf -u :eclairpassword -X POST http://127.0.0.1:8080/getinfo > /dev/null 2>&1; then
+              echo "Eclair is ready"
+              exit 0
+            fi
+            echo "Waiting for Eclair... ($i/60)"
+            sleep 5
+          done
+          echo "Eclair failed to start"
+          docker compose -p ldk-node -f tests/docker/docker-compose-eclair.yml logs eclair
+          exit 1
+
+      - name: Run Eclair 0FC integration tests
+        run: |
+          RUSTFLAGS="--cfg eclair_test --cfg zero_fee_commitment_tests" cargo test --test integration_tests_eclair -- --show-output --test-threads=1

tests/common/scenarios/mod.rs

@@ -20,6 +20,8 @@ use std::time::Duration;
 use bitcoin::Amount;
 use electrsd::corepc_node::Client as BitcoindClient;
 use electrsd::electrum_client::ElectrumApi;
+#[cfg(zero_fee_commitment_tests)]
+use ldk_node::ReserveType;
 use ldk_node::{Event, Node};
 
 use super::external_node::ExternalNode;
@@ -87,15 +89,15 @@ pub(crate) async fn wait_for_htlcs_settled(
 	panic!("HTLCs did not settle on {} channel {} within 15s", peer.name(), ext_channel_id);
 }
 
-/// Build a fresh LDK node configured for interop tests. Uses electrum at the
+/// Build a fresh LDK node configured for interop tests. Uses esplora at the
 /// docker-compose default port and bumps sync timeouts for combo stress.
 pub(crate) fn setup_ldk_node() -> Node {
 	let config = crate::common::random_config();
 	let mut builder = ldk_node::Builder::from_config(config.node_config);
-	let mut sync_config = ldk_node::config::ElectrumSyncConfig::default();
+	let mut sync_config = ldk_node::config::EsploraSyncConfig::default();
 	sync_config.timeouts_config.onchain_wallet_sync_timeout_secs = 180;
 	sync_config.timeouts_config.lightning_wallet_sync_timeout_secs = 120;
-	builder.set_chain_source_electrum("tcp://127.0.0.1:50001".to_string(), Some(sync_config));
+	builder.set_chain_source_esplora("http://127.0.0.1:3002".to_string(), Some(sync_config));
 	let node = builder.build(config.node_entropy).unwrap();
 	node.start().unwrap();
 	node
@@ -164,6 +166,20 @@ pub(crate) async fn basic_channel_cycle_scenario<E: ElectrumApi>(
 	)
 	.await;
 
+	#[cfg(zero_fee_commitment_tests)]
+	{
+		let ext_node_id = peer.get_node_id().await.unwrap();
+		let channel = node
+			.list_channels()
+			.into_iter()
+			.find(|channel| channel.user_channel_id == user_ch)
+			.expect("opened channel should be listed");
+		assert_eq!(channel.counterparty.node_id, ext_node_id);
+		assert!(channel.counterparty.features.supports_anchor_zero_fee_commitments());
+		assert_eq!(channel.feerate_sat_per_1000_weight, 0);
+		assert_eq!(channel.reserve_type, Some(ReserveType::Adaptive));
+	}
+
 	payment::send_bolt11_to_peer(node, peer, 10_000_000, "basic-send").await;
 	payment::receive_bolt11_payment(node, peer, 10_000_000).await;
 

tests/docker/docker-compose-eclair.yml

@@ -77,4 +77,5 @@ services:
         -Declair.bitcoind.zmqtx=tcp://127.0.0.1:28333
         -Declair.features.keysend=optional
         -Declair.on-chain-fees.confirmation-priority.funding=slow
+        ${ECLAIR_EXTRA_JAVA_OPTS:-}
         -Declair.printToConsole