Implement the `UtxoSource` interface for REST/RPC clients

[rust-lightning] / lightning-block-sync / src / rest.rs

diff --git a/lightning-block-sync/src/rest.rs b/lightning-block-sync/src/rest.rs
index 4300893013c06d7a3ee81c715b256066f4d28333..5690da12ea0495c1c8062655a95b27e83611cfa8 100644 (file)
--- a/lightning-block-sync/src/rest.rs
+++ b/lightning-block-sync/src/rest.rs
@@ -3,7 +3,10 @@
 
 use crate::{BlockData, BlockHeaderData, BlockSource, AsyncBlockSourceResult};
 use crate::http::{BinaryResponse, HttpEndpoint, HttpClient, JsonResponse};
+use crate::gossip::UtxoSource;
+use crate::convert::GetUtxosResponse;
 
+use bitcoin::OutPoint;
 use bitcoin::hash_types::BlockHash;
 use bitcoin::hashes::hex::ToHex;
 
@@ -60,11 +63,30 @@ impl BlockSource for RestClient {
        }
 }
 
+impl UtxoSource for RestClient {
+       fn get_block_hash_by_height<'a>(&'a self, block_height: u32) -> AsyncBlockSourceResult<'a, BlockHash> {
+               Box::pin(async move {
+                       let resource_path = format!("blockhashbyheight/{}.bin", block_height);
+                       Ok(self.request_resource::<BinaryResponse, _>(&resource_path).await?)
+               })
+       }
+
+       fn is_output_unspent<'a>(&'a self, outpoint: OutPoint) -> AsyncBlockSourceResult<'a, bool> {
+               Box::pin(async move {
+                       let resource_path = format!("getutxos/{}-{}.json", outpoint.txid.to_hex(), outpoint.vout);
+                       let utxo_result =
+                               self.request_resource::<JsonResponse, GetUtxosResponse>(&resource_path).await?;
+                       Ok(utxo_result.hit_bitmap_nonempty)
+               })
+       }
+}
+
 #[cfg(test)]
 mod tests {
        use super::*;
        use crate::http::BinaryResponse;
        use crate::http::client_tests::{HttpServer, MessageBody};
+       use bitcoin::hashes::Hash;
 
        /// Parses binary data as a string-encoded `u32`.
        impl TryInto<u32> for BinaryResponse {
@@ -113,4 +135,32 @@ mod tests {
                        Ok(n) => assert_eq!(n, 42),
                }
        }
+
+       #[tokio::test]
+       async fn parses_negative_getutxos() {
+               let server = HttpServer::responding_with_ok(MessageBody::Content(
+                       // A real response contains a few more fields, but we actually only look at the
+                       // "bitmap" field, so this should suffice for testing
+                       "{\"chainHeight\": 1, \"bitmap\":\"0\",\"utxos\":[]}"
+               ));
+               let client = RestClient::new(server.endpoint()).unwrap();
+
+               let outpoint = OutPoint::new(bitcoin::Txid::from_inner([0; 32]), 0);
+               let unspent_output = client.is_output_unspent(outpoint).await.unwrap();
+               assert_eq!(unspent_output, false);
+       }
+
+       #[tokio::test]
+       async fn parses_positive_getutxos() {
+               let server = HttpServer::responding_with_ok(MessageBody::Content(
+                       // A real response contains lots more data, but we actually only look at the "bitmap"
+                       // field, so this should suffice for testing
+                       "{\"chainHeight\": 1, \"bitmap\":\"1\",\"utxos\":[]}"
+               ));
+               let client = RestClient::new(server.endpoint()).unwrap();
+
+               let outpoint = OutPoint::new(bitcoin::Txid::from_inner([0; 32]), 0);
+               let unspent_output = client.is_output_unspent(outpoint).await.unwrap();
+               assert_eq!(unspent_output, true);
+       }
 }