Implement quarkdb-verify-checksum command

CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+### New features
+- Implement command ``quarkdb-verify-checksum`` for manually running a full checksum scan.
+
 ### Improvements
 - Security hardening of the redis parser for unauthenticated clients.
 - Package and distribute ``quarkdb-ldb`` tool based on the one provided by RocksDB.

src/Commands.cc

@@ -155,6 +155,7 @@ struct cmdMapInit {
     redis_cmd_map["quarkdb_version"] = {RedisCommand::QUARKDB_VERSION, CommandType::QUARKDB};
     redis_cmd_map["quarkdb_checkpoint"] = {RedisCommand::QUARKDB_CHECKPOINT, CommandType::QUARKDB};
     redis_cmd_map["quarkdb_health"] = {RedisCommand::QUARKDB_HEALTH, CommandType::QUARKDB};
+    redis_cmd_map["quarkdb_verify_checksum"] = {RedisCommand::QUARKDB_VERIFY_CHECKSUM, CommandType::QUARKDB};
 
     // Compatibility: Keep raft_checkpoint, make identical to quarkdb_checkpoint.
     // Maybe remove in a few versions.

src/Commands.hh

@@ -162,6 +162,7 @@ enum class RedisCommand {
   QUARKDB_VERSION,
   QUARKDB_CHECKPOINT,
   QUARKDB_HEALTH,
+  QUARKDB_VERIFY_CHECKSUM,
 
   RECOVERY_GET,
   RECOVERY_SET,

src/Shard.cc

@@ -258,6 +258,19 @@ LinkStatus Shard::dispatch(Connection *conn, RedisRequest &req) {
       stateMachine->getRequestCounter().fillHistorical(headers, data);
       return conn->raw(Formatter::vectorsWithHeaders(headers, data));
     }
+    case RedisCommand::QUARKDB_VERIFY_CHECKSUM: {
+      if(req.size() != 1) return conn->errArgs(req[0]);
+      InFlightRegistration registration(inFlightTracker);
+      if(!registration.ok()) {
+        return conn->err("unavailable");
+      }
+
+      rocksdb::Status st = stateMachine->verifyChecksum();
+
+      std::vector<std::string> output;
+      output.emplace_back(SSTR("state-machine: " << st.ToString()));
+      return conn->statusVector(output);
+    }
     default: {
       if(req.getCommandType() == CommandType::QUARKDB) {
         qdb_critical("Unable to dispatch command '" << req[0] << "' of type QUARKDB");

test/e2e.cc

@@ -821,6 +821,11 @@ TEST_F(Raft_e2e, test_many_redis_commands) {
     "3) \"12345\"\n"
     "4) \"1\"\n"
   );
+
+  ASSERT_REPLY_DESCRIBE(
+    tunnel(leaderID)->exec("quarkdb-verify-checksum").get(),
+    "1) state-machine: OK\n"
+  );
 }
 
 TEST_F(Raft_e2e, DequeTrimming) {