src/kv: add support for fetching implementation specific properties

Only implemented for rocksdb for now.

Signed-off-by: Samuel Just <sjust@redhat.com>

3 files changed, 22 insertions, 0 deletions

diff --git a/src/kv/KeyValueDB.h b/src/kv/KeyValueDB.h
index 2ac43e7daac..0e4fed97cf4 100644
--- a/src/kv/KeyValueDB.h
+++ b/src/kv/KeyValueDB.h
@@ -424,6 +424,17 @@ public:
   virtual PerfCounters *get_perf_counters() {
     return nullptr;
   }
+
+  /**
+   * Access implementation specific integral property corresponding
+   * to passed property and prefic.
+   * Return value is true if property is valid for prefix, populates out.
+   */
+  virtual bool get_property(
+    const std::string &property,
+    uint64_t *out) {
+    return false;
+  }
 protected:
   /// List of matching prefixes/ColumnFamilies and merge operators
   std::vector<std::pair<std::string,
diff --git a/src/kv/RocksDBStore.cc b/src/kv/RocksDBStore.cc
index 65affe40b97..c2a9e917bd4 100644
--- a/src/kv/RocksDBStore.cc
+++ b/src/kv/RocksDBStore.cc
@@ -691,6 +691,13 @@ void RocksDBStore::split_stats(const std::string &s, char delim, std::vector<std
     }
 }
 
+bool RocksDBStore::get_property(
+  const std::string &property,
+  uint64_t *out)
+{
+  return db->GetIntProperty(property, out);
+}
+
 int64_t RocksDBStore::estimate_prefix_size(const string& prefix,
 					   const string& key_prefix)
 {
diff --git a/src/kv/RocksDBStore.h b/src/kv/RocksDBStore.h
index e11d43b9ae1..254f6f3afda 100644
--- a/src/kv/RocksDBStore.h
+++ b/src/kv/RocksDBStore.h
@@ -193,6 +193,10 @@ public:
     return logger;
   }
 
+  bool get_property(
+    const std::string &property,
+    uint64_t *out) final;
+
   int64_t estimate_prefix_size(const string& prefix,
 			       const string& key_prefix) override;