From 4757d295c714dc322b7c99b9de11b28c75303469 Mon Sep 17 00:00:00 2001
From: weizuo93 <weizuo@stu.xjtu.edu.cn>
Date: Wed, 21 Oct 2020 15:49:54 +0800
Subject: [PATCH] Fix bug and optimize implementation logic of tablets web page

---
 be/src/http/action/tablets_info_action.cpp | 20 +++++++++-----------
 be/src/olap/tablet_manager.cpp             |  5 ++++-
 be/src/olap/tablet_manager.h               |  2 +-
 3 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/be/src/http/action/tablets_info_action.cpp b/be/src/http/action/tablets_info_action.cpp
index 2efe02f2d98069..49d41814f63833 100644
--- a/be/src/http/action/tablets_info_action.cpp
+++ b/be/src/http/action/tablets_info_action.cpp
@@ -42,26 +42,24 @@ void TabletsInfoAction::handle(HttpRequest *req) {
 }
 
 EasyJson TabletsInfoAction::get_tablets_info(string tablet_num_to_return) {
-    std::vector<TabletInfo> tablets_info;
-    TabletManager* tablet_manager = StorageEngine::instance()->tablet_manager();
-    tablet_manager->obtain_all_tablets(tablets_info);
-
     int64_t number;
     std::string msg;
     if (tablet_num_to_return == "") {
         number = 1000; // default
         msg = "OK";
     } else if (tablet_num_to_return == "all") {
-        number = tablets_info.size();
+        number = std::numeric_limits<std::int64_t>::max();
         msg = "OK";
     } else if (std::all_of(tablet_num_to_return.begin(), tablet_num_to_return.end(), ::isdigit)) {
-        int64_t tablet_num = std::atol(tablet_num_to_return.c_str());
-        number = tablet_num < tablets_info.size() ? tablet_num : tablets_info.size();
+        number = std::atol(tablet_num_to_return.c_str());
         msg = "OK";
     } else {
         number = 0;
         msg = "Parameter Error";
     }
+    std::vector<TabletInfo> tablets_info;
+    TabletManager* tablet_manager = StorageEngine::instance()->tablet_manager();
+    tablet_manager->obtain_specific_quantity_tablets(tablets_info, number);
 
     EasyJson tablets_info_ej;
     tablets_info_ej["msg"] = msg;
@@ -69,12 +67,12 @@ EasyJson TabletsInfoAction::get_tablets_info(string tablet_num_to_return) {
     EasyJson data = tablets_info_ej.Set("data", EasyJson::kObject);
     data["host"] = _host;
     EasyJson tablets = data.Set("tablets", EasyJson::kArray);
-    for (int64_t i = 0; i < number; i++) {
+    for (TabletInfo tablet_info : tablets_info) {
         EasyJson tablet = tablets.PushBack(EasyJson::kObject);
-        tablet["tablet_id"] = tablets_info[i].tablet_id;
-        tablet["schema_hash"] = tablets_info[i].schema_hash;
+        tablet["tablet_id"] = tablet_info.tablet_id;
+        tablet["schema_hash"] = tablet_info.schema_hash;
     }
-    tablets_info_ej["count"] = number;
+    tablets_info_ej["count"] = tablets_info.size();
     return tablets_info_ej;
 }
 } // namespace doris
diff --git a/be/src/olap/tablet_manager.cpp b/be/src/olap/tablet_manager.cpp
index ce2d1369563d22..29f53be487739e 100644
--- a/be/src/olap/tablet_manager.cpp
+++ b/be/src/olap/tablet_manager.cpp
@@ -1455,11 +1455,14 @@ void TabletManager::_remove_tablet_from_partition(const Tablet& tablet) {
     }
 }
 
-void TabletManager::obtain_all_tablets(vector<TabletInfo> &tablets_info) {
+void TabletManager::obtain_specific_quantity_tablets(vector<TabletInfo> &tablets_info, int64_t num) {
     for (int32 i = 0; i < _tablet_map_lock_shard_size; i++) {
         ReadLock rdlock(&_tablet_map_lock_array[i]);
         for (const auto& item : _tablet_map_array[i]) {
             for (TabletSharedPtr tablet : item.second.table_arr) {
+                if (tablets_info.size() >= num) {
+                    return;
+                }
                 if (tablet == nullptr) {
                     continue;
                 }
diff --git a/be/src/olap/tablet_manager.h b/be/src/olap/tablet_manager.h
index 6222c53746c3f0..9e3aea64a61db3 100644
--- a/be/src/olap/tablet_manager.h
+++ b/be/src/olap/tablet_manager.h
@@ -137,7 +137,7 @@ class TabletManager {
 
     void do_tablet_meta_checkpoint(DataDir* data_dir);
 
-    void  obtain_all_tablets(vector<TabletInfo> &tablets_info);
+    void  obtain_specific_quantity_tablets(vector<TabletInfo> &tablets_info, int64_t num);
 
     void register_clone_tablet(int64_t tablet_id);
     void unregister_clone_tablet(int64_t tablet_id);