Add /r/blockinfo endpoint (#3075)

docs/src/inscriptions/recursion.md

@@ -25,6 +25,7 @@ The recursive endpoints are:
 - `/r/blockhash/<HEIGHT>`: block hash at given block height.
 - `/r/blockhash`: latest block hash.
 - `/r/blockheight`: latest block height.
+- `/r/blockinfo/<QUERY>`: block info. `<QUERY>` may be a block height or block hash.
 - `/r/blocktime`: UNIX time stamp of latest block.
 - `/r/children/<INSCRIPTION_ID>`: the first 100 child inscription ids.
 - `/r/children/<INSCRIPTION_ID>/<PAGE>`: the set of 100 child inscription ids on `<PAGE>`.
@@ -108,3 +109,25 @@ Examples
    "page":49
 }
 ```
+
+- `/r/blockinfo/0`:
+
+```json
+{
+  "bits": 486604799,
+  "chainwork": 0,
+  "confirmations": 0,
+  "difficulty": 0.0,
+  "hash": "000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f",
+  "height": 0,
+  "median_time": null,
+  "merkle_root": "0000000000000000000000000000000000000000000000000000000000000000",
+  "next_block": null,
+  "nonce": 0,
+  "previous_block": null,
+  "target": "00000000ffff0000000000000000000000000000000000000000000000000000",
+  "timestamp": 0,
+  "transaction_count": 0,
+  "version": 1
+}
+```

src/lib.rs

@@ -32,7 +32,7 @@ use {
       locktime::absolute::LockTime,
     },
     consensus::{self, Decodable, Encodable},
-    hash_types::BlockHash,
+    hash_types::{BlockHash, TxMerkleNode},
     hashes::Hash,
     opcodes,
     script::{self, Instruction},
@@ -172,6 +172,10 @@ pub fn timestamp(seconds: u32) -> DateTime<Utc> {
   Utc.timestamp_opt(seconds.into(), 0).unwrap()
 }
 
+fn target_as_block_hash(target: bitcoin::Target) -> BlockHash {
+  BlockHash::from_raw_hash(Hash::from_byte_array(target.to_le_bytes()))
+}
+
 fn unbound_outpoint() -> OutPoint {
   OutPoint {
     txid: Hash::all_zeros(),

src/subcommand/server.rs

@@ -8,8 +8,8 @@ use {
   crate::{
     server_config::ServerConfig,
     templates::{
-      BlockHtml, BlockJson, BlocksHtml, BlocksJson, ChildrenHtml, ChildrenJson, ClockSvg,
-      CollectionsHtml, HomeHtml, InputHtml, InscriptionHtml, InscriptionJson,
+      BlockHtml, BlockInfoJson, BlockJson, BlocksHtml, BlocksJson, ChildrenHtml, ChildrenJson,
+      ClockSvg, CollectionsHtml, HomeHtml, InputHtml, InscriptionHtml, InscriptionJson,
       InscriptionsBlockHtml, InscriptionsHtml, InscriptionsJson, OutputHtml, OutputJson,
       PageContent, PageHtml, PreviewAudioHtml, PreviewCodeHtml, PreviewFontHtml, PreviewImageHtml,
       PreviewMarkdownHtml, PreviewModelHtml, PreviewPdfHtml, PreviewTextHtml, PreviewUnknownHtml,
@@ -124,6 +124,15 @@ impl Display for StaticHtml {
   }
 }
 
+fn chainwork(chainwork: &[u8]) -> u128 {
+  chainwork
+    .iter()
+    .rev()
+    .enumerate()
+    .map(|(i, byte)| u128::from(*byte) * 256u128.pow(i.try_into().unwrap()))
+    .sum()
+}
+
 #[derive(Debug, Parser, Clone)]
 pub struct Server {
   #[arg(
@@ -255,6 +264,7 @@ impl Server {
         )
         .route("/r/blockheight", get(Self::block_height))
         .route("/r/blocktime", get(Self::block_time))
+        .route("/r/blockinfo/:query", get(Self::block_info))
         .route("/r/children/:inscription_id", get(Self::children_recursive))
         .route(
           "/r/children/:inscription_id/:page",
@@ -1054,6 +1064,49 @@ impl Server {
     })
   }
 
+  async fn block_info(
+    Extension(index): Extension<Arc<Index>>,
+    Path(DeserializeFromStr(query)): Path<DeserializeFromStr<BlockQuery>>,
+  ) -> ServerResult<Json<BlockInfoJson>> {
+    task::block_in_place(|| {
+      let hash = match query {
+        BlockQuery::Hash(hash) => hash,
+        BlockQuery::Height(height) => index
+          .block_hash(Some(height))?
+          .ok_or_not_found(|| format!("block {height}"))?,
+      };
+
+      let info = index
+        .block_header_info(hash)?
+        .ok_or_not_found(|| format!("block {hash}"))?;
+
+      let header = index
+        .block_header(hash)?
+        .ok_or_not_found(|| format!("block {hash}"))?;
+
+      Ok(Json(BlockInfoJson {
+        bits: header.bits.to_consensus(),
+        chainwork: chainwork(&info.chainwork),
+        confirmations: info.confirmations,
+        difficulty: info.difficulty,
+        hash,
+        height: info.height.try_into().unwrap(),
+        median_time: info
+          .median_time
+          .map(|median_time| median_time.try_into().unwrap()),
+        merkle_root: info.merkle_root,
+        next_block: info.next_block_hash,
+        nonce: info.nonce,
+        previous_block: info.previous_block_hash,
+        target: target_as_block_hash(header.target()),
+        timestamp: info.time.try_into().unwrap(),
+        transaction_count: info.n_tx.try_into().unwrap(),
+        #[allow(clippy::cast_sign_loss)]
+        version: info.version.to_consensus() as u32,
+      }))
+    })
+  }
+
   async fn block_time(Extension(index): Extension<Arc<Index>>) -> ServerResult<String> {
     task::block_in_place(|| {
       Ok(
@@ -5180,4 +5233,70 @@ next
 
     server.assert_response(format!("/preview/{id}"), StatusCode::OK, "foo");
   }
+
+  #[test]
+  fn chainwork_conversion_to_integer() {
+    assert_eq!(chainwork(&[]), 0);
+    assert_eq!(chainwork(&[1]), 1);
+    assert_eq!(chainwork(&[1, 0]), 256);
+    assert_eq!(chainwork(&[1, 1]), 257);
+    assert_eq!(chainwork(&[1, 0, 0]), 65536);
+    assert_eq!(chainwork(&[1, 0, 1]), 65537);
+    assert_eq!(chainwork(&[1, 1, 1]), 65793);
+  }
+
+  #[test]
+  fn block_info() {
+    let server = TestServer::new();
+
+    pretty_assert_eq!(
+      server.get_json::<BlockInfoJson>("/r/blockinfo/0"),
+      BlockInfoJson {
+        bits: 486604799,
+        chainwork: 0,
+        confirmations: 0,
+        difficulty: 0.0,
+        hash: "000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f"
+          .parse()
+          .unwrap(),
+        height: 0,
+        median_time: None,
+        merkle_root: TxMerkleNode::all_zeros(),
+        next_block: None,
+        nonce: 0,
+        previous_block: None,
+        target: "00000000ffff0000000000000000000000000000000000000000000000000000"
+          .parse()
+          .unwrap(),
+        timestamp: 0,
+        transaction_count: 0,
+        version: 1,
+      },
+    );
+
+    server.mine_blocks(1);
+
+    pretty_assert_eq!(
+      server.get_json::<BlockInfoJson>("/r/blockinfo/1"),
+      BlockInfoJson {
+        bits: 0,
+        chainwork: 0,
+        confirmations: 0,
+        difficulty: 0.0,
+        hash: "56d05060a0280d0712d113f25321158747310ece87ea9e299bde06cf385b8d85"
+          .parse()
+          .unwrap(),
+        height: 1,
+        median_time: None,
+        merkle_root: TxMerkleNode::all_zeros(),
+        next_block: None,
+        nonce: 0,
+        previous_block: None,
+        target: BlockHash::all_zeros(),
+        timestamp: 0,
+        transaction_count: 0,
+        version: 1,
+      },
+    )
+  }
 }

src/templates.rs

@@ -1,7 +1,7 @@
 use {super::*, boilerplate::Boilerplate};
 
 pub(crate) use {
-  block::{BlockHtml, BlockJson},
+  block::{BlockHtml, BlockInfoJson, BlockJson},
   blocks::{BlocksHtml, BlocksJson},
   children::{ChildrenHtml, ChildrenJson},
   clock::ClockSvg,

src/templates/block.rs

@@ -1,9 +1,5 @@
 use super::*;
 
-fn target_as_block_hash(target: bitcoin::Target) -> BlockHash {
-  BlockHash::from_raw_hash(Hash::from_byte_array(target.to_le_bytes()))
-}
-
 #[derive(Boilerplate)]
 pub(crate) struct BlockHtml {
   hash: BlockHash,
@@ -61,6 +57,25 @@ impl BlockJson {
   }
 }
 
+#[derive(Debug, PartialEq, Serialize, Deserialize)]
+pub struct BlockInfoJson {
+  pub bits: u32,
+  pub chainwork: u128,
+  pub confirmations: i32,
+  pub difficulty: f64,
+  pub hash: BlockHash,
+  pub height: u32,
+  pub median_time: Option<u64>,
+  pub merkle_root: TxMerkleNode,
+  pub next_block: Option<BlockHash>,
+  pub nonce: u32,
+  pub previous_block: Option<BlockHash>,
+  pub target: BlockHash,
+  pub timestamp: u64,
+  pub transaction_count: u64,
+  pub version: u32,
+}
+
 impl PageContent for BlockHtml {
   fn title(&self) -> String {
     format!("Block {}", self.height)