Merge pull request #56611 from ClickHouse/revert-56354-pchhetri/yield-leadership-keeper

Revert "Add 4-letter command for yielding/resigning leadership"

docs/en/operations/utilities/clickhouse-keeper-client.md

@@ -12,7 +12,6 @@ A client application to interact with clickhouse-keeper by its native protocol.
 -   `-q QUERY`, `--query=QUERY` — Query to execute. If this parameter is not passed, `clickhouse-keeper-client` will start in interactive mode.
 -   `-h HOST`, `--host=HOST` — Server host. Default value: `localhost`.
 -   `-p N`, `--port=N` — Server port. Default value: 9181
--   `-c FILE_PATH`, `--config-file=FILE_PATH` — Set path of config file to get the connection string. Default value: `config.xml`.
 -   `--connection-timeout=TIMEOUT` — Set connection timeout in seconds. Default value: 10s.
 -   `--session-timeout=TIMEOUT` — Set session timeout in seconds. Default value: 10s.
 -   `--operation-timeout=TIMEOUT` — Set operation timeout in seconds. Default value: 10s.

src/Coordination/CoordinationSettings.cpp

@@ -36,7 +36,7 @@ void CoordinationSettings::loadFromConfig(const String & config_elem, const Poco
 }
 
 
-const String KeeperConfigurationAndSettings::DEFAULT_FOUR_LETTER_WORD_CMD = "conf,cons,crst,envi,ruok,srst,srvr,stat,wchs,dirs,mntr,isro,rcvr,apiv,csnp,lgif,rqld,rclc,clrs,ftfl,ydld";
+const String KeeperConfigurationAndSettings::DEFAULT_FOUR_LETTER_WORD_CMD = "conf,cons,crst,envi,ruok,srst,srvr,stat,wchs,dirs,mntr,isro,rcvr,apiv,csnp,lgif,rqld,rclc,clrs,ftfl";
 
 KeeperConfigurationAndSettings::KeeperConfigurationAndSettings()
     : server_id(NOT_EXIST)

src/Coordination/FourLetterCommand.cpp

@@ -172,9 +172,6 @@ void FourLetterCommandFactory::registerCommands(KeeperDispatcher & keeper_dispat
         FourLetterCommandPtr feature_flags_command = std::make_shared<FeatureFlagsCommand>(keeper_dispatcher);
         factory.registerCommand(feature_flags_command);
 
-        FourLetterCommandPtr yield_leadership_command = std::make_shared<YieldLeadershipCommand>(keeper_dispatcher);
-        factory.registerCommand(yield_leadership_command);
-
         factory.initializeAllowList(keeper_dispatcher);
         factory.setInitialize(true);
     }
@@ -582,10 +579,4 @@ String FeatureFlagsCommand::run()
     return ret.str();
 }
 
-String YieldLeadershipCommand::run()
-{
-    keeper_dispatcher.yieldLeadership();
-    return "Sent yield leadership request to leader.";
-}
-
 }

src/Coordination/FourLetterCommand.h

@@ -415,17 +415,4 @@ struct FeatureFlagsCommand : public IFourLetterCommand
     ~FeatureFlagsCommand() override = default;
 };
 
-/// Yield leadership and become follower.
-struct YieldLeadershipCommand : public IFourLetterCommand
-{
-    explicit YieldLeadershipCommand(KeeperDispatcher & keeper_dispatcher_)
-        : IFourLetterCommand(keeper_dispatcher_)
-    {
-    }
-
-    String name() override { return "ydld"; }
-    String run() override;
-    ~YieldLeadershipCommand() override = default;
-};
-
 }

src/Coordination/KeeperDispatcher.h

@@ -237,12 +237,6 @@ public:
         return server->requestLeader();
     }
 
-    /// Yield leadership and become follower.
-    void yieldLeadership()
-    {
-        return server->yieldLeadership();
-    }
-
     void recalculateStorageStats()
     {
         return server->recalculateStorageStats();

src/Coordination/KeeperServer.cpp

@@ -1101,12 +1101,6 @@ bool KeeperServer::requestLeader()
     return isLeader() || raft_instance->request_leadership();
 }
 
-void KeeperServer::yieldLeadership()
-{
-    if (isLeader())
-        raft_instance->yield_leadership();
-}
-
 void KeeperServer::recalculateStorageStats()
 {
     state_machine->recalculateStorageStats();

src/Coordination/KeeperServer.h

@@ -144,8 +144,6 @@ public:
 
     bool requestLeader();
 
-    void yieldLeadership();
-
     void recalculateStorageStats();
 };
 

tests/integration/helpers/keeper_utils.py

@@ -248,11 +248,6 @@ def is_leader(cluster, node, port=9181):
     return "Mode: leader" in stat
 
 
-def is_follower(cluster, node, port=9181):
-    stat = send_4lw_cmd(cluster, node, "stat", port)
-    return "Mode: follower" in stat
-
-
 def get_leader(cluster, nodes):
     for node in nodes:
         if is_leader(cluster, node):

tests/integration/test_keeper_four_word_command/test.py

@@ -725,26 +725,3 @@ def test_cmd_clrs(started_cluster):
 
     finally:
         destroy_zk_client(zk)
-
-
-def test_cmd_ydld(started_cluster):
-    wait_nodes()
-    for node in [node1, node3]:
-        data = keeper_utils.send_4lw_cmd(cluster, node, cmd="ydld")
-        assert data == "Sent yield leadership request to leader."
-
-        print("ydld output -------------------------------------")
-        print(data)
-
-        if keeper_utils.is_leader(cluster, node):
-            # wait for it to yield leadership
-            retry = 0
-            while keeper_utils.is_leader(cluster, node) and retry < 30:
-                time.sleep(1)
-                retry += 1
-            if retry == 30:
-                print(
-                    node.name
-                    + " did not yield leadership after 30s, maybe there is something wrong."
-                )
-        assert keeper_utils.is_follower(cluster, node)