Implement Get block nullifiers

zaino-fetch/src/chain/block.rs

@@ -13,7 +13,9 @@ use crate::{
 };
 use sha2::{Digest, Sha256};
 use std::io::Cursor;
-use zaino_proto::proto::compact_formats::{ChainMetadata, CompactBlock};
+use zaino_proto::proto::compact_formats::{
+    ChainMetadata, CompactBlock, CompactOrchardAction, CompactTx,
+};
 
 /// A block header, containing metadata about a block.
 ///
@@ -428,3 +430,51 @@ pub async fn get_block_from_node(
         Err(e) => Err(e.into()),
     }
 }
+
+/// Returns a compact block holding only action nullifiers.
+///
+/// Retrieves a full block from zebrad/zcashd using 2 get_block calls.
+/// This is because a get_block verbose = 1 call is require to fetch txids.
+///
+/// TODO / NOTE: This should be rewritten when the BlockCache is added.
+pub async fn get_nullifiers_from_node(
+    zebra_uri: &http::Uri,
+    height: &u32,
+) -> Result<CompactBlock, BlockCacheError> {
+    match get_block_from_node(zebra_uri, height).await {
+        Ok(block) => Ok(CompactBlock {
+            proto_version: block.proto_version,
+            height: block.height,
+            hash: block.hash,
+            prev_hash: block.prev_hash,
+            time: block.time,
+            header: block.header,
+            vtx: block
+                .vtx
+                .into_iter()
+                .map(|tx| CompactTx {
+                    index: tx.index,
+                    hash: tx.hash,
+                    fee: tx.fee,
+                    spends: tx.spends,
+                    outputs: Vec::new(),
+                    actions: tx
+                        .actions
+                        .into_iter()
+                        .map(|action| CompactOrchardAction {
+                            nullifier: action.nullifier,
+                            cmx: Vec::new(),
+                            ephemeral_key: Vec::new(),
+                            ciphertext: Vec::new(),
+                        })
+                        .collect(),
+                })
+                .collect(),
+            chain_metadata: Some(ChainMetadata {
+                sapling_commitment_tree_size: 0,
+                orchard_commitment_tree_size: 0,
+            }),
+        }),
+        Err(e) => Err(e.into()),
+    }
+}

zaino-serve/src/rpc/service.rs

@@ -6,7 +6,10 @@ use tokio_stream::wrappers::ReceiverStream;
 
 use crate::{rpc::GrpcClient, utils::get_build_info};
 use zaino_fetch::{
-    chain::{block::get_block_from_node, mempool::Mempool},
+    chain::{
+        block::{get_block_from_node, get_nullifiers_from_node},
+        mempool::Mempool,
+    },
     jsonrpc::{connector::JsonRpcConnector, response::GetTransactionResponse},
 };
 use zaino_proto::proto::{
@@ -156,11 +159,10 @@ impl CompactTxStreamer for GrpcClient {
 
     /// Same as GetBlock except actions contain only nullifiers.
     ///
-    /// This RPC has not been implemented as it is not currently used by zingolib.
-    /// If you require this RPC please open an issue or PR at the Zingo-Indexer github (https://github.com/zingolabs/zingo-indexer).
+    /// NOTE: This should be reimplemented with the introduction of the BlockCache.
     fn get_block_nullifiers<'life0, 'async_trait>(
         &'life0 self,
-        _request: tonic::Request<BlockId>,
+        request: tonic::Request<BlockId>,
     ) -> core::pin::Pin<
         Box<
             dyn core::future::Future<
@@ -175,7 +177,14 @@ impl CompactTxStreamer for GrpcClient {
     {
         println!("[TEST] Received call of get_block_nullifiers.");
         Box::pin(async {
-            Err(tonic::Status::unimplemented("get_block_nullifiers not yet implemented. If you require this RPC please open an issue or PR at the Zingo-Indexer github (https://github.com/zingolabs/zingo-indexer)."))
+            let zebrad_uri = self.zebrad_uri.clone();
+            let height = request.into_inner().height as u32;
+            match get_nullifiers_from_node(&zebrad_uri, &height).await {
+                Ok(block) => Ok(tonic::Response::new(block)),
+                Err(e) => {
+                    return Err(tonic::Status::internal(e.to_string()));
+                }
+            }
         })
     }