Make a dedicated IndexDb

processor/scanner/src/index/db.rs

@@ -0,0 +1,34 @@
+use serai_db::{Get, DbTxn, create_db};
+
+create_db!(
+  ScannerIndex {
+    // A lookup of a block's number to its ID
+    BlockId: (number: u64) -> [u8; 32],
+    // A lookup of a block's ID to its number
+    BlockNumber: (id: [u8; 32]) -> u64,
+
+    // The latest finalized block to appear on the blockchain
+    LatestFinalizedBlock: () -> u64,
+  }
+);
+
+pub(crate) struct IndexDb;
+impl IndexDb {
+  pub(crate) fn set_block(txn: &mut impl DbTxn, number: u64, id: [u8; 32]) {
+    BlockId::set(txn, number, &id);
+    BlockNumber::set(txn, id, &number);
+  }
+  pub(crate) fn block_id(getter: &impl Get, number: u64) -> Option<[u8; 32]> {
+    BlockId::get(getter, number)
+  }
+  pub(crate) fn block_number(getter: &impl Get, id: [u8; 32]) -> Option<u64> {
+    BlockNumber::get(getter, id)
+  }
+
+  pub(crate) fn set_latest_finalized_block(txn: &mut impl DbTxn, latest_finalized_block: u64) {
+    LatestFinalizedBlock::set(txn, &latest_finalized_block);
+  }
+  pub(crate) fn latest_finalized_block(getter: &impl Get) -> Option<u64> {
+    LatestFinalizedBlock::get(getter)
+  }
+}