encapsulate meta_cf (#2335)

src/cluster_info.rs

@@ -20,7 +20,7 @@ use crate::crds_gossip::CrdsGossip;
 use crate::crds_gossip_error::CrdsGossipError;
 use crate::crds_gossip_pull::CRDS_GOSSIP_PULL_CRDS_TIMEOUT_MS;
 use crate::crds_value::{CrdsValue, CrdsValueLabel, LeaderId};
-use crate::db_ledger::{DbLedger, LedgerColumnFamily, MetaCf, DEFAULT_SLOT_HEIGHT};
+use crate::db_ledger::DbLedger;
 use crate::packet::{to_shared_blob, Blob, SharedBlob, BLOB_SIZE};
 use crate::result::Result;
 use crate::rpc::RPC_PORT;
@@ -871,7 +871,7 @@ impl ClusterInfo {
         ix: u64,
     ) -> Vec<SharedBlob> {
         if let Some(db_ledger) = db_ledger {
-            let meta = db_ledger.meta_cf.get(&MetaCf::key(DEFAULT_SLOT_HEIGHT));
+            let meta = db_ledger.meta();
 
             if let Ok(Some(meta)) = meta {
                 let max_slot = meta.received_slot;

src/db_ledger.rs

@@ -275,7 +275,7 @@ impl LedgerColumnFamilyRaw for ErasureCf {
 pub struct DbLedger {
     // Underlying database is automatically closed in the Drop implementation of DB
     db: Arc<DB>,
-    pub meta_cf: MetaCf,
+    meta_cf: MetaCf,
     pub data_cf: DataCf,
     pub erasure_cf: ErasureCf,
 }
@@ -330,6 +330,10 @@ impl DbLedger {
         })
     }
 
+    pub fn meta(&self) -> Result<Option<SlotMeta>> {
+        self.meta_cf.get(&MetaCf::key(DEFAULT_SLOT_HEIGHT))
+    }
+
     pub fn destroy(ledger_path: &str) -> Result<()> {
         // DB::destroy() fails if `ledger_path` doesn't exist
         create_dir_all(&ledger_path)?;

src/db_window.rs

@@ -32,7 +32,7 @@ pub fn repair(
 ) -> Result<Vec<(SocketAddr, Vec<u8>)>> {
     let rcluster_info = cluster_info.read().unwrap();
     let mut is_next_leader = false;
-    let meta = db_ledger.meta_cf.get(&MetaCf::key(DEFAULT_SLOT_HEIGHT))?;
+    let meta = db_ledger.meta()?;
     if meta.is_none() {
         return Ok(vec![]);
     }
@@ -325,8 +325,7 @@ pub fn process_blob(
     // then stop
     if max_ix != 0 && !consumed_entries.is_empty() {
         let meta = db_ledger
-            .meta_cf
+            .meta()?
-            .get(&MetaCf::key(DEFAULT_SLOT_HEIGHT))?
             .expect("Expect metadata to exist if consumed entries is nonzero");
 
         let consumed = meta.consumed;
@@ -367,7 +366,7 @@ pub fn calculate_max_repair_entry_height(
 
 #[cfg(feature = "erasure")]
 fn try_erasure(db_ledger: &Arc<DbLedger>, consume_queue: &mut Vec<Entry>) -> Result<()> {
-    let meta = db_ledger.meta_cf.get(&MetaCf::key(DEFAULT_SLOT_HEIGHT))?;
+    let meta = db_ledger.meta()?;
 
     if let Some(meta) = meta {
         let (data, coding) = erasure::recover(db_ledger, meta.consumed_slot, meta.consumed)?;

src/window_service.rs

@@ -2,7 +2,7 @@
 //!
 use crate::cluster_info::ClusterInfo;
 use crate::counter::Counter;
-use crate::db_ledger::{DbLedger, LedgerColumnFamily, MetaCf, DEFAULT_SLOT_HEIGHT};
+use crate::db_ledger::DbLedger;
 use crate::db_window::*;
 use crate::entry::EntrySender;
 
@@ -158,7 +158,7 @@ pub fn window_service(
                     }
                 }
 
-                let meta = db_ledger.meta_cf.get(&MetaCf::key(DEFAULT_SLOT_HEIGHT));
+                let meta = db_ledger.meta();
 
                 if let Ok(Some(meta)) = meta {
                     let received = meta.received;