Add healthcheck to YDB CLI

%%
pnv1@mr-nvme-testing-04:~/arcadia$ kikimr/public/tools/ydb/ydb -p ydb-ru mon healthcheck
Healthcheck status: GOOD
pnv1@mr-nvme-testing-04:~/arcadia$ kikimr/public/tools/ydb/ydb -p ydb-ru mon healthcheck --format json
{
 "self_check_result": "GOOD"
}
pnv1@mr-nvme-testing-04:~/arcadia$ kikimr/public/tools/ydb/ydb -p ydb-vla-dev02 mon healthcheck                                                                                              Healthcheck status: DEGRADED
For more info use "--format json" option
pnv1@mr-nvme-testing-04:~/arcadia$ kikimr/public/tools/ydb/ydb -p ydb-vla-dev02 mon healthcheck --format json
{
 "self_check_result": "DEGRADED",
 "issue_log": [
  {
   "id": "YELLOW-be81",
   "status": "YELLOW",
   "message": "Database has storage issues",
   "location": {
    "database": {
     "name": "/dev02/home/xenoxeno/db1"
    }
   },
   "reason": [
    ""
   ],
   "type": "DATABASE",
   "level": 1
  },
  {
   "id": "",
   "status": "YELLOW",
   "message": "Storage degraded",
   "location": {
    "database": {
     "name": "/dev02/home/xenoxeno/db1"
    }
   },
...
%%

4 files changed, 143 insertions, 0 deletions

diff --git a/ydb/public/lib/ydb_cli/commands/CMakeLists.txt b/ydb/public/lib/ydb_cli/commands/CMakeLists.txt
index fe8e547a3ae..89c9fbba660 100644
--- a/ydb/public/lib/ydb_cli/commands/CMakeLists.txt
+++ b/ydb/public/lib/ydb_cli/commands/CMakeLists.txt
@@ -26,6 +26,7 @@ target_link_libraries(clicommands PUBLIC
   cpp-client-ydb_discovery
   cpp-client-ydb_export
   cpp-client-ydb_import
+  cpp-client-ydb_monitoring
   cpp-client-ydb_operation
   cpp-client-ydb_persqueue_public
   cpp-client-ydb_proto
@@ -43,6 +44,7 @@ target_sources(clicommands PRIVATE
   ${CMAKE_SOURCE_DIR}/ydb/public/lib/ydb_cli/commands/ydb_service_discovery.cpp
   ${CMAKE_SOURCE_DIR}/ydb/public/lib/ydb_cli/commands/ydb_service_export.cpp
   ${CMAKE_SOURCE_DIR}/ydb/public/lib/ydb_cli/commands/ydb_service_import.cpp
+  ${CMAKE_SOURCE_DIR}/ydb/public/lib/ydb_cli/commands/ydb_service_monitoring.cpp
   ${CMAKE_SOURCE_DIR}/ydb/public/lib/ydb_cli/commands/ydb_service_operation.cpp
   ${CMAKE_SOURCE_DIR}/ydb/public/lib/ydb_cli/commands/ydb_service_scheme.cpp
   ${CMAKE_SOURCE_DIR}/ydb/public/lib/ydb_cli/commands/ydb_service_scripting.cpp
diff --git a/ydb/public/lib/ydb_cli/commands/ydb_root_common.cpp b/ydb/public/lib/ydb_cli/commands/ydb_root_common.cpp
index 31805fd27e6..3ba870aba0c 100644
--- a/ydb/public/lib/ydb_cli/commands/ydb_root_common.cpp
+++ b/ydb/public/lib/ydb_cli/commands/ydb_root_common.cpp
@@ -4,6 +4,7 @@
 #include "ydb_service_export.h"
 #include "ydb_service_import.h"
 #include "ydb_service_operation.h"
+#include "ydb_service_monitoring.h"
 #include "ydb_service_scheme.h"
 #include "ydb_service_scripting.h"
 #include "ydb_service_table.h"
@@ -33,6 +34,7 @@ TClientCommandRootCommon::TClientCommandRootCommon(const TClientSettings& settin
     AddCommand(std::make_unique<TCommandTools>());
     AddCommand(std::make_unique<TCommandExport>(Settings.UseExportToYt.GetRef()));
     AddCommand(std::make_unique<TCommandImport>());
+    AddCommand(std::make_unique<TCommandMonitoring>());
     AddCommand(std::make_unique<TCommandOperation>());
     AddCommand(std::make_unique<TCommandConfig>());
     AddCommand(std::make_unique<TCommandInit>());
diff --git a/ydb/public/lib/ydb_cli/commands/ydb_service_monitoring.cpp b/ydb/public/lib/ydb_cli/commands/ydb_service_monitoring.cpp
new file mode 100644
index 00000000000..2b28ee7f76a
--- /dev/null
+++ b/ydb/public/lib/ydb_cli/commands/ydb_service_monitoring.cpp
@@ -0,0 +1,108 @@
+#include "ydb_service_monitoring.h"
+
+#include <ydb/public/api/grpc/ydb_monitoring_v1.grpc.pb.h>
+#include <ydb/public/sdk/cpp/client/ydb_proto/accessor.h>
+
+namespace NYdb {
+namespace NConsoleClient {
+
+TCommandMonitoring::TCommandMonitoring()
+    : TClientCommandTree("monitoring", {"mon"}, "Monitoring service operations")
+{
+    AddCommand(std::make_unique<TCommandSelfCheck>());
+}
+
+TCommandSelfCheck::TCommandSelfCheck()
+    : TYdbSimpleCommand("healthcheck", {"selfcheck"}, "Self check. Returns status of the database")
+{}
+
+void TCommandSelfCheck::Config(TConfig& config) {
+    TYdbSimpleCommand::Config(config);
+    config.SetFreeArgsNum(0);
+
+    AddFormats(config, { EOutputFormat::Pretty, EOutputFormat::Json });
+
+    config.Opts->AddLongOption('v', "verbose", "Return detailed info about components checked with their statuses.")
+        .StoreTrue(&Verbose);
+}
+
+void TCommandSelfCheck::Parse(TConfig& config) {
+    TYdbSimpleCommand::Parse(config);
+    ParseFormats();
+}
+
+int TCommandSelfCheck::Run(TConfig& config) {
+    NMonitoring::TMonitoringClient client(CreateDriver(config));
+    NMonitoring::TSelfCheckSettings settings;
+
+    if (Verbose) {
+        settings.ReturnVerboseStatus(true);
+    }
+
+    NMonitoring::TSelfCheckResult result = client.SelfCheck(
+        FillSettings(settings)
+    ).GetValueSync();
+    ThrowOnError(result);
+    return PrintResponse(result);
+}
+
+int TCommandSelfCheck::PrintResponse(NMonitoring::TSelfCheckResult& result) {
+    const auto& proto = NYdb::TProtoAccessor::GetProto(result);
+    switch (OutputFormat) {
+        case EOutputFormat::Default:
+        case EOutputFormat::Pretty:
+        {
+            NColorizer::TColors colors = NColorizer::AutoColors(Cout);
+            TStringBuf statusColor;
+            auto hcResultString = SelfCheck_Result_Name(proto.Getself_check_result());
+            switch (proto.Getself_check_result()) {
+                case Ydb::Monitoring::SelfCheck::GOOD:
+                    statusColor = colors.GreenColor();
+                    break;
+                case Ydb::Monitoring::SelfCheck::DEGRADED:
+                    statusColor = colors.YellowColor();
+                    break;
+                case Ydb::Monitoring::SelfCheck::MAINTENANCE_REQUIRED:
+                    // Orange-ish
+                    statusColor = colors.IsTTY() ? "\033[88;91m" : "";
+                    break;
+                case Ydb::Monitoring::SelfCheck::EMERGENCY:
+                    statusColor = colors.RedColor();
+                    break;
+                case Ydb::Monitoring::SelfCheck::UNSPECIFIED:
+                    statusColor = colors.OldColor();
+                    break;
+                default:
+                    Cout << "Unknown healthcheck status: " << hcResultString << Endl;
+                    return EXIT_FAILURE;
+            }
+
+            Cout << "Healthcheck status: " << statusColor << hcResultString << colors.OldColor() << Endl;
+            if (proto.Getself_check_result() != Ydb::Monitoring::SelfCheck::GOOD) {
+                Cerr << "For more info use \"--format json\" option" << Endl;
+            }
+            break;
+        }
+        case EOutputFormat::Json:
+        {
+            TString json;

+            google::protobuf::util::JsonPrintOptions jsonOpts;

+            jsonOpts.preserve_proto_field_names = true;

+            jsonOpts.add_whitespace = true;

+            auto convertStatus = google::protobuf::util::MessageToJsonString(proto, &json, jsonOpts);

+            if (convertStatus.ok()) {

+                Cout << json;

+            } else {

+                Cerr << "Error occurred while converting result proto to json" << Endl;

+                return EXIT_FAILURE;

+            }
+            break;
+        }

+        default:

+            throw TMisuseException() << "This command doesn't support " << OutputFormat << " output format";
+    }
+    return EXIT_SUCCESS;
+}
+
+}
+}
diff --git a/ydb/public/lib/ydb_cli/commands/ydb_service_monitoring.h b/ydb/public/lib/ydb_cli/commands/ydb_service_monitoring.h
new file mode 100644
index 00000000000..d5454593808
--- /dev/null
+++ b/ydb/public/lib/ydb_cli/commands/ydb_service_monitoring.h
@@ -0,0 +1,31 @@
+#pragma once
+
+#include "ydb_command.h"
+#include "ydb_common.h"
+

+#include <ydb/public/lib/ydb_cli/common/format.h>
+#include <ydb/public/sdk/cpp/client/ydb_monitoring/monitoring.h>
+
+namespace NYdb {
+namespace NConsoleClient {
+
+class TCommandMonitoring : public TClientCommandTree {
+public:
+    TCommandMonitoring();
+};
+
+class TCommandSelfCheck : public TYdbSimpleCommand, public TCommandWithFormat {
+public:
+    TCommandSelfCheck();
+    void Config(TConfig& config) override;
+    void Parse(TConfig& config) override;
+    int Run(TConfig& config) override;
+
+private:
+    int PrintResponse(NMonitoring::TSelfCheckResult& result);
+
+    bool Verbose = false;
+};
+
+}
+}