feat: add header by number provider fn (#299)

* feat: add header by number provider fn

* Update crates/interfaces/src/provider/block.rs

Co-authored-by: rakita <rakita@users.noreply.github.com>

Co-authored-by: rakita <rakita@users.noreply.github.com>

crates/consensus/src/verification.rs

@@ -417,6 +417,10 @@ mod tests {
         fn header(&self, _block_number: &BlockHash) -> Result<Option<Header>> {
             Ok(self.parent.clone())
         }
+
+        fn header_by_number(&self, _num: u64) -> Result<Option<Header>> {
+            Ok(self.parent.clone())
+        }
     }
     /// got test block
     fn mock_block() -> (BlockLocked, Header) {

crates/interfaces/src/provider/block.rs

@@ -2,7 +2,7 @@ use crate::Result;
 use auto_impl::auto_impl;
 use reth_primitives::{
     rpc::{BlockId, BlockNumber},
-    Block, BlockHash, Header, H256, U256,
+    Block, BlockHash, BlockHashOrNumber, Header, H256, U256,
 };
 
 /// Client trait for fetching `Header` related data.
@@ -15,6 +15,17 @@ pub trait HeaderProvider: Send + Sync {
 
     /// Get header by block hash
     fn header(&self, block_hash: &BlockHash) -> Result<Option<Header>>;
+
+    /// Get header by block number
+    fn header_by_number(&self, num: u64) -> Result<Option<Header>>;
+
+    /// Get header by block number or hash
+    fn header_by_hash_or_number(&self, hash_or_num: BlockHashOrNumber) -> Result<Option<Header>> {
+        match hash_or_num {
+            BlockHashOrNumber::Hash(hash) => self.header(&hash),
+            BlockHashOrNumber::Number(num) => self.header_by_number(num),
+        }
+    }
 }
 
 /// Api trait for fetching `Block` related data.

crates/interfaces/src/provider/db_provider/block.rs

@@ -2,16 +2,18 @@ use crate::{
     db::{tables, Database, DbTx},
     provider::{HeaderProvider, ProviderImpl},
 };
+use reth_primitives::{BlockNumber, Header};
 
 impl<DB: Database> HeaderProvider for ProviderImpl<DB> {
-    fn header(
-        &self,
-        block_hash: &reth_primitives::BlockHash,
-    ) -> crate::Result<Option<reth_primitives::Header>> {
+    fn header(&self, block_hash: &reth_primitives::BlockHash) -> crate::Result<Option<Header>> {
         self.db.view(|tx| tx.get::<tables::Headers>((0, *block_hash).into()))?.map_err(Into::into)
     }
 
-    fn is_known(&self, block_hash: &reth_primitives::BlockHash) -> crate::Result<bool> {
-        self.header(block_hash).map(|header| header.is_some())
+    fn header_by_number(&self, num: BlockNumber) -> crate::Result<Option<Header>> {
+        if let Some(hash) = self.db.view(|tx| tx.get::<tables::CanonicalHeaders>(num))?? {
+            self.header(&hash)
+        } else {
+            Ok(None)
+        }
     }
 }