Add skeleton for sharded rocksdb KVS. (#7181)

fdbserver/CMakeLists.txt

@@ -54,6 +54,7 @@ set(FDBSERVER_SRCS
   KeyValueStoreCompressTestData.actor.cpp
   KeyValueStoreMemory.actor.cpp
   KeyValueStoreRocksDB.actor.cpp
+  KeyValueStoreShardedRocksDB.actor.cpp
   KeyValueStoreSQLite.actor.cpp
   KmsConnector.h
   KmsConnectorInterface.h

fdbserver/IKeyValueStore.h

@@ -91,6 +91,15 @@ public:
 	                                      int byteLimit = 1 << 30,
 	                                      ReadType type = ReadType::NORMAL) = 0;
 
+	// Shard management APIs.
+	virtual Future<Void> addRange(KeyRangeRef range, std::string id) { return Void(); }
+
+	virtual std::vector<std::string> removeRange(KeyRangeRef range) { return std::vector<std::string>(); }
+
+	virtual void persistRangeMapping(KeyRangeRef range, bool isAdd) {}
+
+	virtual Future<Void> cleanUpShardsIfNeeded(const std::vector<std::string>& shardIds) { return Void(); };
+
 	// To debug MEMORY_RADIXTREE type ONLY
 	// Returns (1) how many key & value pairs have been inserted (2) how many nodes have been created (3) how many
 	// key size is less than 12 bytes

tests/CMakeLists.txt

@@ -190,9 +190,11 @@ if(WITH_PYTHON)
   add_fdb_test(TEST_FILES noSim/RandomUnitTests.toml UNIT)
   if (WITH_ROCKSDB_EXPERIMENTAL)
     add_fdb_test(TEST_FILES noSim/KeyValueStoreRocksDBTest.toml)
+    add_fdb_test(TEST_FILES noSim/ShardedRocksDBTest.toml)
     add_fdb_test(TEST_FILES fast/PhysicalShardMove.toml)
   else()
     add_fdb_test(TEST_FILES noSim/KeyValueStoreRocksDBTest.toml IGNORE)
+    add_fdb_test(TEST_FILES noSim/ShardedRocksDBTest.toml IGNORE)
     add_fdb_test(TEST_FILES fast/PhysicalShardMove.toml IGNORE)
   endif()
   add_fdb_test(TEST_FILES rare/CheckRelocation.toml)

tests/noSim/ShardedRocksDBTest.toml

@@ -0,0 +1,9 @@
+[[test]]
+ testTitle = 'UnitTests'
+ useDB = false
+ startDelay = 0
+
+     [[test.workload]]
+     testName = 'UnitTests'
+     maxTestCases = 10
+     testsMatching = 'noSim/ShardedRocksDB/'