feat: iterator for select_block_headers

CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Enhancements
 
 - Add an optional open-telemetry trace exporter (#659).
+- Taking iterator in select_block_headers (#667).
 
 ### Changes
 

crates/store/src/db/mod.rs

@@ -250,12 +250,14 @@ impl Db {
 
     /// Loads multiple block headers from the DB.
     #[instrument(target = COMPONENT, skip_all, ret(level = "debug"), err)]
-    pub async fn select_block_headers(&self, blocks: impl Iterator<Item = BlockNumber>) -> Result<Vec<BlockHeader>> {
-        let block_vec: Vec<BlockNumber> = blocks.collect();
+    pub async fn select_block_headers(
+        &self,
+        blocks: impl Iterator<Item = BlockNumber> + Send + 'static,
+    ) -> Result<Vec<BlockHeader>> {
         self.pool
             .get()
             .await?
-            .interact(move |conn| sql::select_block_headers(conn, &block_vec))
+            .interact(move |conn| sql::select_block_headers(conn, blocks))
             .await
             .map_err(|err| {
                 DatabaseError::InteractError(format!(

crates/store/src/db/sql/mod.rs

@@ -1059,11 +1059,11 @@ pub fn select_block_header_by_block_num(
 /// A vector of [`BlockHeader`] or an error.
 pub fn select_block_headers(
     conn: &mut Connection,
-    blocks: &[BlockNumber],
+    blocks: impl Iterator<Item = BlockNumber> + Send,
 ) -> Result<Vec<BlockHeader>> {
-    let mut headers = Vec::with_capacity(blocks.len());
+    let blocks: Vec<Value> = blocks.map(|b| b.as_u32().into()).collect();
 
-    let blocks: Vec<Value> = blocks.iter().copied().map(|b| b.as_u32().into()).collect();
+    let mut headers = Vec::with_capacity(blocks.len());
     let mut stmt = conn
         .prepare_cached("SELECT block_header FROM block_headers WHERE block_num IN rarray(?1);")?;
     let mut rows = stmt.query(params![Rc::new(blocks)])?;

crates/store/src/state.rs

@@ -477,7 +477,8 @@ impl State {
             (chain_length.into(), paths)
         };
 
-        let headers = self.db.select_block_headers(blocks.iter().copied()).await?;
+        let headers = self.db.select_block_headers(blocks.into_iter()).await?;
+
         let headers = headers
             .into_iter()
             .map(|header| (header.block_num(), header))