show inbound fees in channel policy

C-Otto · May 3, 2024 · 04aeaac · 04aeaac
1 parent 93c40af
commit 04aeaac
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Showing 10 changed files with 824 additions and 57 deletions.
diff --git a/grpc-adapter/src/main/java/de/cotto/lndmanagej/grpc/GrpcPolicy.java b/grpc-adapter/src/main/java/de/cotto/lndmanagej/grpc/GrpcPolicy.java
@@ -1,20 +1,40 @@
 package de.cotto.lndmanagej.grpc;
 
+import com.google.protobuf.ByteString;
 import de.cotto.lndmanagej.model.Coins;
 import de.cotto.lndmanagej.model.Policy;
 import lnrpc.RoutingPolicy;
 import org.springframework.stereotype.Component;
 
+import java.nio.IntBuffer;
+
 @Component
 public class GrpcPolicy {
+
+    private static final int FEE_RECORD_TYPE = 55_555;
+
     public GrpcPolicy() {
         // default constructor
     }
 
     public Policy toPolicy(RoutingPolicy routingPolicy) {
+        long inboundFeeRate;
+        Coins inboundBaseFee;
+        if (routingPolicy.containsCustomRecords(FEE_RECORD_TYPE)) {
+            ByteString record = routingPolicy.getCustomRecordsOrThrow(FEE_RECORD_TYPE);
+            IntBuffer intBuffer = record.asReadOnlyByteBuffer().asIntBuffer();
+            inboundBaseFee = Coins.ofMilliSatoshis(intBuffer.get());
+            inboundFeeRate = intBuffer.get();
+        } else {
+            inboundFeeRate = 0;
+            inboundBaseFee = Coins.NONE;
+        }
+
         return new Policy(
                 routingPolicy.getFeeRateMilliMsat(),
                 Coins.ofMilliSatoshis(routingPolicy.getFeeBaseMsat()),
+                inboundFeeRate,
+                inboundBaseFee,
                 !routingPolicy.getDisabled(),
                 routingPolicy.getTimeLockDelta(),
                 Coins.ofMilliSatoshis(routingPolicy.getMinHtlc()),

diff --git a/grpc-adapter/src/test/java/de/cotto/lndmanagej/grpc/GrpcChannelPolicyTest.java b/grpc-adapter/src/test/java/de/cotto/lndmanagej/grpc/GrpcChannelPolicyTest.java
@@ -1,5 +1,6 @@
 package de.cotto.lndmanagej.grpc;
 
+import com.google.protobuf.ByteString;
 import de.cotto.lndmanagej.model.Coins;
 import de.cotto.lndmanagej.model.Policy;
 import de.cotto.lndmanagej.model.Pubkey;
@@ -20,6 +21,7 @@
 import static de.cotto.lndmanagej.model.PubkeyFixtures.PUBKEY_3;
 import static de.cotto.lndmanagej.model.PubkeyFixtures.PUBKEY_4;
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.SoftAssertions.assertSoftly;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.lenient;
 import static org.mockito.Mockito.when;
@@ -163,6 +165,49 @@ void getOtherPubkey_no_matching_pubkey() {
         assertThat(grpcChannelPolicy.getOtherPubkey(CHANNEL_ID, PUBKEY_4)).isEmpty();
     }
 
+    @Test
+    void getPolicy_with_unknown_custom_records() {
+        when(grpcService.getChannelEdge(CHANNEL_ID)).thenReturn(Optional.of(
+                edgeWithCustomRecord(123, ByteString.copyFromUtf8("test"))
+        ));
+        Policy policy = grpcChannelPolicy.getPolicyTo(CHANNEL_ID, PUBKEY_2).orElseThrow();
+
+        assertSoftly(softly -> {
+            softly.assertThat(policy.inboundFeeRate()).isEqualTo(0L);
+            softly.assertThat(policy.inboundBaseFee()).isEqualTo(Coins.NONE);
+        });
+    }
+
+    @Test
+    void getPolicy_with_negative_inbound_fees() {
+        ByteString inboundBaseFee = ByteString.fromHex(Integer.toHexString(-456));
+        ByteString inboundFeeRate = ByteString.fromHex(Integer.toHexString(-123));
+        ByteString value = inboundBaseFee.concat(inboundFeeRate);
+
+        when(grpcService.getChannelEdge(CHANNEL_ID)).thenReturn(Optional.of(
+                edgeWithCustomRecord(55_555, value)
+        ));
+        Policy policy = grpcChannelPolicy.getPolicyTo(CHANNEL_ID, PUBKEY_2).orElseThrow();
+
+        assertSoftly(softly -> {
+            softly.assertThat(policy.inboundBaseFee()).isEqualTo(Coins.ofMilliSatoshis(-456));
+            softly.assertThat(policy.inboundFeeRate()).isEqualTo(-123L);
+        });
+    }
+
+    @Test
+    void getPolicy_with_negative_inbound_fees_using_hex_string() {
+        when(grpcService.getChannelEdge(CHANNEL_ID)).thenReturn(Optional.of(
+                edgeWithCustomRecord(55_555, ByteString.fromHex("00000000fffffe0c"))
+        ));
+        Policy policy = grpcChannelPolicy.getPolicyTo(CHANNEL_ID, PUBKEY_2).orElseThrow();
+
+        assertSoftly(softly -> {
+            softly.assertThat(policy.inboundBaseFee()).isEqualTo(Coins.NONE);
+            softly.assertThat(policy.inboundFeeRate()).isEqualTo(-500L);
+        });
+    }
+
     private ChannelEdge channelEdge(Pubkey firstPubkey, Pubkey secondPubkey) {
         return ChannelEdge.newBuilder()
                 .setNode1Pub(firstPubkey.toString())
@@ -172,6 +217,15 @@ private ChannelEdge channelEdge(Pubkey firstPubkey, Pubkey secondPubkey) {
                 .build();
     }
 
+    private ChannelEdge edgeWithCustomRecord(int key, ByteString value) {
+        return ChannelEdge.newBuilder()
+                .setNode1Pub(PUBKEY.toString())
+                .setNode2Pub(PUBKEY_2.toString())
+                .setNode1Policy(policyWithCustomRecord(key, value))
+                .setNode2Policy(routingPolicy(FEE_RATE_SECOND))
+                .build();
+    }
+
     private RoutingPolicy routingPolicy(int feeRate) {
         return RoutingPolicy.newBuilder()
                 .setFeeRateMilliMsat(feeRate)
@@ -180,4 +234,14 @@ private RoutingPolicy routingPolicy(int feeRate) {
                 .setMaxHtlcMsat(MAX_HTLC.milliSatoshis())
                 .build();
     }
+
+    private RoutingPolicy policyWithCustomRecord(long key, ByteString value) {
+        return RoutingPolicy.newBuilder()
+                .setFeeRateMilliMsat(FEE_RATE_FIRST)
+                .setTimeLockDelta(TIME_LOCK_DELTA)
+                .setMinHtlc(MIN_HTLC.milliSatoshis())
+                .setMaxHtlcMsat(MAX_HTLC.milliSatoshis())
+                .putCustomRecords(key, value)
+                .build();
+    }
 }