Added parents recursive endpoint

docs/src/inscriptions/recursion.md

@@ -42,6 +42,8 @@ The recursive endpoints are:
 - `/r/children/<INSCRIPTION_ID>/<PAGE>`: the set of 100 child inscription ids on `<PAGE>`.
 - `/r/inscription/<INSCRIPTION_ID>`: information about an inscription
 - `/r/metadata/<INSCRIPTION_ID>`: JSON string containing the hex-encoded CBOR metadata.
+- `/r/parents/<INSCRIPTION_ID>`: the first 100 parent inscription ids.
+- `/r/parents/<INSCRIPTION_ID>/<PAGE>`: the set of 100 parent inscription ids on `<PAGE>`.
 - `/r/sat/<SAT_NUMBER>`: the first 100 inscription ids on a sat.
 - `/r/sat/<SAT_NUMBER>/<PAGE>`: the set of 100 inscription ids on `<PAGE>`.
 - `/r/sat/<SAT_NUMBER>/at/<INDEX>`: the inscription id at `<INDEX>` of all inscriptions on a sat. `<INDEX>` may be a negative number to index from the back. `0` being the first and `-1` being the most recent for example.

src/subcommand/server.rs

@@ -242,6 +242,11 @@ impl Server {
           get(Self::children_recursive_paginated),
         )
         .route("/r/metadata/:inscription_id", get(Self::metadata))
+        .route("/r/parents/:inscription_id", get(Self::parents_recursive))
+        .route(
+          "/r/parents/:inscription_id/:page",
+          get(Self::parents_recursive_paginated),
+        )
         .route("/r/sat/:sat_number", get(Self::sat_inscriptions))
         .route(
           "/r/sat/:sat_number/:page",
@@ -1902,6 +1907,38 @@ impl Server {
     })
   }
 
+  async fn parents_recursive(
+    Extension(index): Extension<Arc<Index>>,
+    Path(inscription_id): Path<InscriptionId>,
+  ) -> ServerResult {
+    Self::parents_recursive_paginated(Extension(index), Path((inscription_id, 0))).await
+  }
+
+  async fn parents_recursive_paginated(
+    Extension(index): Extension<Arc<Index>>,
+    Path((inscription_id, page)): Path<(InscriptionId, usize)>,
+  ) -> ServerResult {
+    task::block_in_place(|| {
+      let child = index
+        .get_inscription_entry(inscription_id)?
+        .ok_or_not_found(|| format!("inscription {inscription_id}"))?;
+
+      let (ids, more) = index.get_parents_by_sequence_number_paginated(child.parents, page)?;
+
+      let page_index =
+        u32::try_from(page).map_err(|_| anyhow!("page index {} out of range", page))?;
+
+      Ok(
+        Json(api::Inscriptions {
+          ids,
+          more,
+          page_index,
+        })
+        .into_response(),
+      )
+    })
+  }
+
   async fn sat_inscriptions(
     Extension(index): Extension<Arc<Index>>,
     Path(sat): Path<u64>,
@@ -6031,6 +6068,75 @@ next
     assert_eq!(children_json.page, 1);
   }
 
+  #[test]
+  fn parents_recursive_endpoint() {
+    let server = TestServer::builder().chain(Chain::Regtest).build();
+    server.mine_blocks(1);
+
+    let mut parent_ids = Vec::new();
+    let mut inputs = Vec::new();
+    for i in 0..111 {
+      parent_ids.push(InscriptionId {
+        txid: server.core.broadcast_tx(TransactionTemplate {
+          inputs: &[(i + 1, 0, 0, inscription("text/plain", "hello").to_witness())],
+          ..default()
+        }),
+        index: 0,
+      });
+
+      inputs.push((i + 2, 1, 0, Witness::default()));
+
+      server.mine_blocks(1);
+    }
+
+    inputs.insert(
+      0,
+      (
+        112,
+        0,
+        0,
+        Inscription {
+          content_type: Some("text/plain".into()),
+          body: Some("hello".into()),
+          parents: parent_ids.iter().map(|id| id.value()).collect(),
+          ..default()
+        }
+        .to_witness(),
+      ),
+    );
+
+    let txid = server.core.broadcast_tx(TransactionTemplate {
+      inputs: &inputs,
+      ..default()
+    });
+
+    server.mine_blocks(1);
+
+    let inscription_id = InscriptionId { txid, index: 0 };
+
+    let first_parent_inscription_id = parent_ids[0];
+    let hundredth_parent_inscription_id = parent_ids[99];
+    let hundred_first_parent_inscription_id = parent_ids[100];
+    let hundred_eleventh_parent_inscription_id = parent_ids[110];
+
+    let parents_json = server.get_json::<api::Inscriptions>(format!("/r/parents/{inscription_id}"));
+
+    assert_eq!(parents_json.ids.len(), 100);
+    assert_eq!(parents_json.ids[0], first_parent_inscription_id);
+    assert_eq!(parents_json.ids[99], hundredth_parent_inscription_id);
+    assert!(parents_json.more);
+    assert_eq!(parents_json.page_index, 0);
+
+    let parents_json =
+      server.get_json::<api::Inscriptions>(format!("/r/parents/{inscription_id}/1"));
+
+    assert_eq!(parents_json.ids.len(), 11);
+    assert_eq!(parents_json.ids[0], hundred_first_parent_inscription_id);
+    assert_eq!(parents_json.ids[10], hundred_eleventh_parent_inscription_id);
+    assert!(!parents_json.more);
+    assert_eq!(parents_json.page_index, 1);
+  }
+
   #[test]
   fn inscriptions_in_block_page() {
     let server = TestServer::builder()