diff --git a/cpp/src/cache/Cache.h b/cpp/src/cache/Cache.h
index b2a57ebdfb2d8c38e37e04cc01521127cd4de31e..b526e9339f7197ddc7f75d1c0384c48b23878c6c 100644
--- a/cpp/src/cache/Cache.h
+++ b/cpp/src/cache/Cache.h
@@ -32,30 +32,40 @@ namespace cache {
 
 template<typename ItemObj>
 class Cache {
-public:
+ public:
     //mem_capacity, units:GB
     Cache(int64_t capacity_gb, uint64_t cache_max_count);
     ~Cache() = default;
 
-    int64_t usage() const { return usage_; }
-    int64_t capacity() const { return capacity_; } //unit: BYTE
+    int64_t usage() const {
+        return usage_;
+    }
+
+    int64_t capacity() const {
+        return capacity_;
+    } //unit: BYTE
     void set_capacity(int64_t capacity); //unit: BYTE
 
-    double freemem_percent() const { return freemem_percent_; };
-    void set_freemem_percent(double percent) { freemem_percent_ = percent; }
+    double freemem_percent() const {
+        return freemem_percent_;
+    }
+
+    void set_freemem_percent(double percent) {
+        freemem_percent_ = percent;
+    }
 
     size_t size() const;
-    bool exists(const std::string& key);
-    ItemObj get(const std::string& key);
-    void insert(const std::string& key, const ItemObj& item);
-    void erase(const std::string& key);
+    bool exists(const std::string &key);
+    ItemObj get(const std::string &key);
+    void insert(const std::string &key, const ItemObj &item);
+    void erase(const std::string &key);
     void print();
     void clear();
 
-private:
+ private:
     void free_memory();
 
-private:
+ private:
     int64_t usage_;
     int64_t capacity_;
     double freemem_percent_;
@@ -64,8 +74,8 @@ private:
     mutable std::mutex mutex_;
 };
 
-}   // cache
-}   // milvus
-}   // zilliz
+} // namespace cache
+} // namespace milvus
+} // namespace zilliz
 
-#include "cache/Cache.inl"
\ No newline at end of file
+#include "cache/Cache.inl"
diff --git a/cpp/src/cache/Cache.inl b/cpp/src/cache/Cache.inl
index 3eaffc45568debd547fa33810d4ccd4c955e8578..ebd8f3c25d2b23fd5adce6e3d50e36efb26a7e0e 100644
--- a/cpp/src/cache/Cache.inl
+++ b/cpp/src/cache/Cache.inl
@@ -33,29 +33,33 @@ Cache<ItemObj>::Cache(int64_t capacity, uint64_t cache_max_count)
 }
 
 template<typename ItemObj>
-void Cache<ItemObj>::set_capacity(int64_t capacity) {
-    if(capacity > 0) {
+void
+Cache<ItemObj>::set_capacity(int64_t capacity) {
+    if (capacity > 0) {
         capacity_ = capacity;
         free_memory();
     }
 }
 
 template<typename ItemObj>
-size_t Cache<ItemObj>::size() const {
+size_t
+Cache<ItemObj>::size() const {
     std::lock_guard<std::mutex> lock(mutex_);
     return lru_.size();
 }
 
 template<typename ItemObj>
-bool Cache<ItemObj>::exists(const std::string& key) {
+bool
+Cache<ItemObj>::exists(const std::string &key) {
     std::lock_guard<std::mutex> lock(mutex_);
     return lru_.exists(key);
 }
 
 template<typename ItemObj>
-ItemObj Cache<ItemObj>::get(const std::string& key) {
+ItemObj
+Cache<ItemObj>::get(const std::string &key) {
     std::lock_guard<std::mutex> lock(mutex_);
-    if(!lru_.exists(key)){
+    if (!lru_.exists(key)) {
         return nullptr;
     }
 
@@ -63,8 +67,9 @@ ItemObj Cache<ItemObj>::get(const std::string& key) {
 }
 
 template<typename ItemObj>
-void Cache<ItemObj>::insert(const std::string& key, const ItemObj& item) {
-    if(item == nullptr) {
+void
+Cache<ItemObj>::insert(const std::string &key, const ItemObj &item) {
+    if (item == nullptr) {
         return;
     }
 
@@ -80,7 +85,7 @@ void Cache<ItemObj>::insert(const std::string& key, const ItemObj& item) {
 
         //if key already exist, subtract old item size
         if (lru_.exists(key)) {
-            const ItemObj& old_item = lru_.get(key);
+            const ItemObj &old_item = lru_.get(key);
             usage_ -= old_item->size();
         }
 
@@ -107,13 +112,14 @@ void Cache<ItemObj>::insert(const std::string& key, const ItemObj& item) {
 }
 
 template<typename ItemObj>
-void Cache<ItemObj>::erase(const std::string& key) {
+void
+Cache<ItemObj>::erase(const std::string &key) {
     std::lock_guard<std::mutex> lock(mutex_);
-    if(!lru_.exists(key)){
+    if (!lru_.exists(key)) {
         return;
     }
 
-    const ItemObj& old_item = lru_.get(key);
+    const ItemObj &old_item = lru_.get(key);
     usage_ -= old_item->size();
 
     SERVER_LOG_DEBUG << "Erase " << key << " size: " << old_item->size();
@@ -122,7 +128,8 @@ void Cache<ItemObj>::erase(const std::string& key) {
 }
 
 template<typename ItemObj>
-void Cache<ItemObj>::clear() {
+void
+Cache<ItemObj>::clear() {
     std::lock_guard<std::mutex> lock(mutex_);
     lru_.clear();
     usage_ = 0;
@@ -131,12 +138,13 @@ void Cache<ItemObj>::clear() {
 
 /* free memory space when CACHE occupation exceed its capacity */
 template<typename ItemObj>
-void Cache<ItemObj>::free_memory() {
+void
+Cache<ItemObj>::free_memory() {
     if (usage_ <= capacity_) return;
 
     int64_t threshhold = capacity_ * freemem_percent_;
     int64_t delta_size = usage_ - threshhold;
-    if(delta_size <= 0) {
+    if (delta_size <= 0) {
         delta_size = 1;//ensure at least one item erased
     }
 
@@ -148,8 +156,8 @@ void Cache<ItemObj>::free_memory() {
 
         auto it = lru_.rbegin();
         while (it != lru_.rend() && released_size < delta_size) {
-            auto& key = it->first;
-            auto& obj_ptr = it->second;
+            auto &key = it->first;
+            auto &obj_ptr = it->second;
 
             key_array.emplace(key);
             released_size += obj_ptr->size();
@@ -159,7 +167,7 @@ void Cache<ItemObj>::free_memory() {
 
     SERVER_LOG_DEBUG << "to be released memory size: " << released_size;
 
-    for (auto& key : key_array) {
+    for (auto &key : key_array) {
         erase(key);
     }
 
@@ -167,7 +175,8 @@ void Cache<ItemObj>::free_memory() {
 }
 
 template<typename ItemObj>
-void Cache<ItemObj>::print() {
+void
+Cache<ItemObj>::print() {
     size_t cache_count = 0;
     {
         std::lock_guard<std::mutex> lock(mutex_);
@@ -179,7 +188,7 @@ void Cache<ItemObj>::print() {
     SERVER_LOG_DEBUG << "[Cache capacity]: " << capacity_ << " bytes";
 }
 
-}   // cache
-}   // milvus
-}   // zilliz
+} // namespace cache
+} // namespace milvus
+} // namespace zilliz
 
diff --git a/cpp/src/cache/CacheMgr.h b/cpp/src/cache/CacheMgr.h
index 1dd630e14dc7a1507b881431f8e620b94e943c1e..53004d10b23b41a90a7090a114f2ad730e05bff9 100644
--- a/cpp/src/cache/CacheMgr.h
+++ b/cpp/src/cache/CacheMgr.h
@@ -22,22 +22,25 @@
 #include "utils/Log.h"
 #include "metrics/Metrics.h"
 
+#include <string>
+#include <memory>
+
 namespace zilliz {
 namespace milvus {
 namespace cache {
 
 template<typename ItemObj>
 class CacheMgr {
-public:
+ public:
     virtual uint64_t ItemCount() const;
 
-    virtual bool ItemExists(const std::string& key);
+    virtual bool ItemExists(const std::string &key);
 
-    virtual ItemObj GetItem(const std::string& key);
+    virtual ItemObj GetItem(const std::string &key);
 
-    virtual void InsertItem(const std::string& key, const ItemObj& data);
+    virtual void InsertItem(const std::string &key, const ItemObj &data);
 
-    virtual void EraseItem(const std::string& key);
+    virtual void EraseItem(const std::string &key);
 
     virtual void PrintInfo();
 
@@ -47,18 +50,17 @@ public:
     int64_t CacheCapacity() const;
     void SetCapacity(int64_t capacity);
 
-protected:
+ protected:
     CacheMgr();
     virtual ~CacheMgr();
 
-protected:
+ protected:
     using CachePtr = std::shared_ptr<Cache<ItemObj>>;
     CachePtr cache_;
 };
 
+} // namespace cache
+} // namespace milvus
+} // namespace zilliz
 
-}
-}
-}
-
-#include "cache/CacheMgr.inl"
\ No newline at end of file
+#include "cache/CacheMgr.inl"
diff --git a/cpp/src/cache/CacheMgr.inl b/cpp/src/cache/CacheMgr.inl
index 36c3d94642d7372f96522810c40cca93c19ce774..b0c47b3dc37f54b6b336fe26f3b292d45ba5697f 100644
--- a/cpp/src/cache/CacheMgr.inl
+++ b/cpp/src/cache/CacheMgr.inl
@@ -30,18 +30,20 @@ CacheMgr<ItemObj>::~CacheMgr() {
 }
 
 template<typename ItemObj>
-uint64_t CacheMgr<ItemObj>::ItemCount() const {
-    if(cache_ == nullptr) {
+uint64_t
+CacheMgr<ItemObj>::ItemCount() const {
+    if (cache_ == nullptr) {
         SERVER_LOG_ERROR << "Cache doesn't exist";
         return 0;
     }
 
-    return (uint64_t)(cache_->size());
+    return (uint64_t) (cache_->size());
 }
 
 template<typename ItemObj>
-bool CacheMgr<ItemObj>::ItemExists(const std::string& key) {
-    if(cache_ == nullptr) {
+bool
+CacheMgr<ItemObj>::ItemExists(const std::string &key) {
+    if (cache_ == nullptr) {
         SERVER_LOG_ERROR << "Cache doesn't exist";
         return false;
     }
@@ -50,8 +52,9 @@ bool CacheMgr<ItemObj>::ItemExists(const std::string& key) {
 }
 
 template<typename ItemObj>
-ItemObj CacheMgr<ItemObj>::GetItem(const std::string& key) {
-    if(cache_ == nullptr) {
+ItemObj
+CacheMgr<ItemObj>::GetItem(const std::string &key) {
+    if (cache_ == nullptr) {
         SERVER_LOG_ERROR << "Cache doesn't exist";
         return nullptr;
     }
@@ -60,8 +63,9 @@ ItemObj CacheMgr<ItemObj>::GetItem(const std::string& key) {
 }
 
 template<typename ItemObj>
-void CacheMgr<ItemObj>::InsertItem(const std::string& key, const ItemObj& data) {
-    if(cache_ == nullptr) {
+void
+CacheMgr<ItemObj>::InsertItem(const std::string &key, const ItemObj &data) {
+    if (cache_ == nullptr) {
         SERVER_LOG_ERROR << "Cache doesn't exist";
         return;
     }
@@ -71,8 +75,9 @@ void CacheMgr<ItemObj>::InsertItem(const std::string& key, const ItemObj& data)
 }
 
 template<typename ItemObj>
-void CacheMgr<ItemObj>::EraseItem(const std::string& key) {
-    if(cache_ == nullptr) {
+void
+CacheMgr<ItemObj>::EraseItem(const std::string &key) {
+    if (cache_ == nullptr) {
         SERVER_LOG_ERROR << "Cache doesn't exist";
         return;
     }
@@ -82,8 +87,9 @@ void CacheMgr<ItemObj>::EraseItem(const std::string& key) {
 }
 
 template<typename ItemObj>
-void CacheMgr<ItemObj>::PrintInfo() {
-    if(cache_ == nullptr) {
+void
+CacheMgr<ItemObj>::PrintInfo() {
+    if (cache_ == nullptr) {
         SERVER_LOG_ERROR << "Cache doesn't exist";
         return;
     }
@@ -92,8 +98,9 @@ void CacheMgr<ItemObj>::PrintInfo() {
 }
 
 template<typename ItemObj>
-void CacheMgr<ItemObj>::ClearCache() {
-    if(cache_ == nullptr) {
+void
+CacheMgr<ItemObj>::ClearCache() {
+    if (cache_ == nullptr) {
         SERVER_LOG_ERROR << "Cache doesn't exist";
         return;
     }
@@ -102,8 +109,9 @@ void CacheMgr<ItemObj>::ClearCache() {
 }
 
 template<typename ItemObj>
-int64_t CacheMgr<ItemObj>::CacheUsage() const {
-    if(cache_ == nullptr) {
+int64_t
+CacheMgr<ItemObj>::CacheUsage() const {
+    if (cache_ == nullptr) {
         SERVER_LOG_ERROR << "Cache doesn't exist";
         return 0;
     }
@@ -112,8 +120,9 @@ int64_t CacheMgr<ItemObj>::CacheUsage() const {
 }
 
 template<typename ItemObj>
-int64_t CacheMgr<ItemObj>::CacheCapacity() const {
-    if(cache_ == nullptr) {
+int64_t
+CacheMgr<ItemObj>::CacheCapacity() const {
+    if (cache_ == nullptr) {
         SERVER_LOG_ERROR << "Cache doesn't exist";
         return 0;
     }
@@ -122,14 +131,15 @@ int64_t CacheMgr<ItemObj>::CacheCapacity() const {
 }
 
 template<typename ItemObj>
-void CacheMgr<ItemObj>::SetCapacity(int64_t capacity) {
-    if(cache_ == nullptr) {
+void
+CacheMgr<ItemObj>::SetCapacity(int64_t capacity) {
+    if (cache_ == nullptr) {
         SERVER_LOG_ERROR << "Cache doesn't exist";
         return;
     }
     cache_->set_capacity(capacity);
 }
 
-}
-}
-}
+} // namespace cache
+} // namespace milvus
+} // namespace zilliz
diff --git a/cpp/src/cache/CpuCacheMgr.cpp b/cpp/src/cache/CpuCacheMgr.cpp
index 1f93ec92bdd006d4e445f2308d9fb3e860e5e0e8..d26004b2bef5a843700a288075f825022f5db565 100644
--- a/cpp/src/cache/CpuCacheMgr.cpp
+++ b/cpp/src/cache/CpuCacheMgr.cpp
@@ -16,20 +16,22 @@
 // under the License.
 
 
-#include "CpuCacheMgr.h"
+#include "cache/CpuCacheMgr.h"
 #include "server/Config.h"
 #include "utils/Log.h"
 
+#include <utility>
+
 namespace zilliz {
 namespace milvus {
 namespace cache {
 
 namespace {
-    constexpr int64_t unit = 1024 * 1024 * 1024;
+constexpr int64_t unit = 1024 * 1024 * 1024;
 }
 
 CpuCacheMgr::CpuCacheMgr() {
-    server::Config& config = server::Config::GetInstance();
+    server::Config &config = server::Config::GetInstance();
     Status s;
 
     int32_t cpu_mem_cap;
@@ -38,7 +40,7 @@ CpuCacheMgr::CpuCacheMgr() {
         SERVER_LOG_ERROR << s.message();
     }
     int64_t cap = cpu_mem_cap * unit;
-    cache_ = std::make_shared<Cache<DataObjPtr>>(cap, 1UL<<32);
+    cache_ = std::make_shared<Cache<DataObjPtr>>(cap, 1UL << 32);
 
     float cpu_mem_threshold;
     s = config.GetCacheConfigCpuMemThreshold(cpu_mem_threshold);
@@ -53,20 +55,22 @@ CpuCacheMgr::CpuCacheMgr() {
     }
 }
 
-CpuCacheMgr* CpuCacheMgr::GetInstance() {
+CpuCacheMgr *
+CpuCacheMgr::GetInstance() {
     static CpuCacheMgr s_mgr;
     return &s_mgr;
 }
 
-engine::VecIndexPtr CpuCacheMgr::GetIndex(const std::string& key) {
+engine::VecIndexPtr
+CpuCacheMgr::GetIndex(const std::string &key) {
     DataObjPtr obj = GetItem(key);
-    if(obj != nullptr) {
+    if (obj != nullptr) {
         return obj->data();
     }
 
     return nullptr;
 }
 
-}
-}
-}
\ No newline at end of file
+} // namespace cache
+} // namespace milvus
+} // namespace zilliz
diff --git a/cpp/src/cache/CpuCacheMgr.h b/cpp/src/cache/CpuCacheMgr.h
index 5a2cdb599acdc8a7e846e0251179746ab39f52b0..32a83c4cc0dd6a510f3d9386e410db5651951d8b 100644
--- a/cpp/src/cache/CpuCacheMgr.h
+++ b/cpp/src/cache/CpuCacheMgr.h
@@ -20,21 +20,24 @@
 #include "CacheMgr.h"
 #include "DataObj.h"
 
+#include <string>
+#include <memory>
+
 namespace zilliz {
 namespace milvus {
 namespace cache {
 
 class CpuCacheMgr : public CacheMgr<DataObjPtr> {
-private:
+ private:
     CpuCacheMgr();
 
-public:
+ public:
     //TODO: use smart pointer instead
-    static CpuCacheMgr* GetInstance();
+    static CpuCacheMgr *GetInstance();
 
-    engine::VecIndexPtr GetIndex(const std::string& key);
+    engine::VecIndexPtr GetIndex(const std::string &key);
 };
 
-}
-}
-}
+} // namespace cache
+} // namespace milvus
+} // namespace zilliz
diff --git a/cpp/src/cache/DataObj.h b/cpp/src/cache/DataObj.h
index f9215bc152096c1444297a2b954d16351cd54e2e..6ed3256eee1bb22f7a9535af666deceab4509a9b 100644
--- a/cpp/src/cache/DataObj.h
+++ b/cpp/src/cache/DataObj.h
@@ -27,38 +27,43 @@ namespace milvus {
 namespace cache {
 
 class DataObj {
-public:
-    DataObj(const engine::VecIndexPtr& index)
-            : index_(index)
-    {}
+ public:
+    explicit DataObj(const engine::VecIndexPtr &index)
+        : index_(index) {
+    }
 
-    DataObj(const engine::VecIndexPtr& index, int64_t size)
-            : index_(index),
-              size_(size)
-    {}
+    DataObj(const engine::VecIndexPtr &index, int64_t size)
+        : index_(index),
+          size_(size) {
+    }
 
-    engine::VecIndexPtr data() { return index_; }
-    const engine::VecIndexPtr& data() const { return index_; }
+    engine::VecIndexPtr data() {
+        return index_;
+    }
+
+    const engine::VecIndexPtr &data() const {
+        return index_;
+    }
 
     int64_t size() const {
-        if(index_ == nullptr) {
+        if (index_ == nullptr) {
             return 0;
         }
 
-        if(size_ > 0) {
+        if (size_ > 0) {
             return size_;
         }
 
         return index_->Count() * index_->Dimension() * sizeof(float);
     }
 
-private:
+ private:
     engine::VecIndexPtr index_ = nullptr;
     int64_t size_ = 0;
 };
 
 using DataObjPtr = std::shared_ptr<DataObj>;
 
-}
-}
-}
\ No newline at end of file
+} // namespace cache
+} // namespace milvus
+} // namespace zilliz
diff --git a/cpp/src/cache/GpuCacheMgr.cpp b/cpp/src/cache/GpuCacheMgr.cpp
index 5c104ba0e7452fa9eea6de8c0dc30bf566664d9b..ad68a6ebef47ee903e954796abbb05affd4c3192 100644
--- a/cpp/src/cache/GpuCacheMgr.cpp
+++ b/cpp/src/cache/GpuCacheMgr.cpp
@@ -16,11 +16,13 @@
 // under the License.
 
 
-#include <sstream>
+#include "cache/GpuCacheMgr.h"
 #include "utils/Log.h"
-#include "GpuCacheMgr.h"
 #include "server/Config.h"
 
+#include <sstream>
+#include <utility>
+
 namespace zilliz {
 namespace milvus {
 namespace cache {
@@ -29,11 +31,11 @@ std::mutex GpuCacheMgr::mutex_;
 std::unordered_map<uint64_t, GpuCacheMgrPtr> GpuCacheMgr::instance_;
 
 namespace {
-    constexpr int64_t G_BYTE = 1024 * 1024 * 1024;
+constexpr int64_t G_BYTE = 1024 * 1024 * 1024;
 }
 
 GpuCacheMgr::GpuCacheMgr() {
-    server::Config& config = server::Config::GetInstance();
+    server::Config &config = server::Config::GetInstance();
     Status s;
 
     int32_t gpu_mem_cap;
@@ -42,7 +44,7 @@ GpuCacheMgr::GpuCacheMgr() {
         SERVER_LOG_ERROR << s.message();
     }
     int32_t cap = gpu_mem_cap * G_BYTE;
-    cache_ = std::make_shared<Cache<DataObjPtr>>(cap, 1UL<<32);
+    cache_ = std::make_shared<Cache<DataObjPtr>>(cap, 1UL << 32);
 
     float gpu_mem_threshold;
     s = config.GetCacheConfigGpuMemThreshold(gpu_mem_threshold);
@@ -57,7 +59,8 @@ GpuCacheMgr::GpuCacheMgr() {
     }
 }
 
-GpuCacheMgr* GpuCacheMgr::GetInstance(uint64_t gpu_id) {
+GpuCacheMgr *
+GpuCacheMgr::GetInstance(uint64_t gpu_id) {
     if (instance_.find(gpu_id) == instance_.end()) {
         std::lock_guard<std::mutex> lock(mutex_);
         if (instance_.find(gpu_id) == instance_.end()) {
@@ -70,15 +73,16 @@ GpuCacheMgr* GpuCacheMgr::GetInstance(uint64_t gpu_id) {
     }
 }
 
-engine::VecIndexPtr GpuCacheMgr::GetIndex(const std::string& key) {
+engine::VecIndexPtr
+GpuCacheMgr::GetIndex(const std::string &key) {
     DataObjPtr obj = GetItem(key);
-    if(obj != nullptr) {
+    if (obj != nullptr) {
         return obj->data();
     }
 
     return nullptr;
 }
 
-}
-}
-}
\ No newline at end of file
+} // namespace cache
+} // namespace milvus
+} // namespace zilliz
diff --git a/cpp/src/cache/GpuCacheMgr.h b/cpp/src/cache/GpuCacheMgr.h
index 57539b698192fc5858633f31040d06d1483a177a..843a5ff67d7a5479c9c54e677345701ae7125fee 100644
--- a/cpp/src/cache/GpuCacheMgr.h
+++ b/cpp/src/cache/GpuCacheMgr.h
@@ -21,6 +21,7 @@
 
 #include <unordered_map>
 #include <memory>
+#include <string>
 
 namespace zilliz {
 namespace milvus {
@@ -30,18 +31,18 @@ class GpuCacheMgr;
 using GpuCacheMgrPtr = std::shared_ptr<GpuCacheMgr>;
 
 class GpuCacheMgr : public CacheMgr<DataObjPtr> {
-public:
+ public:
     GpuCacheMgr();
 
-    static GpuCacheMgr* GetInstance(uint64_t gpu_id);
+    static GpuCacheMgr *GetInstance(uint64_t gpu_id);
 
-    engine::VecIndexPtr GetIndex(const std::string& key);
+    engine::VecIndexPtr GetIndex(const std::string &key);
 
-private:
+ private:
     static std::mutex mutex_;
     static std::unordered_map<uint64_t, GpuCacheMgrPtr> instance_;
 };
 
-}
-}
-}
+} // namespace cache
+} // namespace milvus
+} // namespace zilliz
diff --git a/cpp/src/cache/LRU.h b/cpp/src/cache/LRU.h
index a4f4dcf5f21106f74de79bb70961a31f53c862ea..5446dd0f14ec909c761f05f125fcc13d3d4bfcaa 100644
--- a/cpp/src/cache/LRU.h
+++ b/cpp/src/cache/LRU.h
@@ -22,6 +22,7 @@
 #include <list>
 #include <cstddef>
 #include <stdexcept>
+#include <utility>
 
 namespace zilliz {
 namespace milvus {
@@ -29,14 +30,15 @@ namespace cache {
 
 template<typename key_t, typename value_t>
 class LRU {
-public:
+ public:
     typedef typename std::pair<key_t, value_t> key_value_pair_t;
     typedef typename std::list<key_value_pair_t>::iterator list_iterator_t;
     typedef typename std::list<key_value_pair_t>::reverse_iterator reverse_list_iterator_t;
 
-    LRU(size_t max_size) : max_size_(max_size) {}
+    explicit LRU(size_t max_size) : max_size_(max_size) {
+    }
 
-    void put(const key_t& key, const value_t& value) {
+    void put(const key_t &key, const value_t &value) {
         auto it = cache_items_map_.find(key);
         cache_items_list_.push_front(key_value_pair_t(key, value));
         if (it != cache_items_map_.end()) {
@@ -53,7 +55,7 @@ public:
         }
     }
 
-    const value_t& get(const key_t& key) {
+    const value_t &get(const key_t &key) {
         auto it = cache_items_map_.find(key);
         if (it == cache_items_map_.end()) {
             throw std::range_error("There is no such key in cache");
@@ -63,7 +65,7 @@ public:
         }
     }
 
-    void erase(const key_t& key) {
+    void erase(const key_t &key) {
         auto it = cache_items_map_.find(key);
         if (it != cache_items_map_.end()) {
             cache_items_list_.erase(it->second);
@@ -71,7 +73,7 @@ public:
         }
     }
 
-    bool exists(const key_t& key) const {
+    bool exists(const key_t &key) const {
         return cache_items_map_.find(key) != cache_items_map_.end();
     }
 
@@ -101,14 +103,14 @@ public:
         cache_items_map_.clear();
     }
 
-private:
+ private:
     std::list<key_value_pair_t> cache_items_list_;
     std::unordered_map<key_t, list_iterator_t> cache_items_map_;
     size_t max_size_;
     list_iterator_t iter_;
 };
 
-}   // cache
-}   // milvus
-}   // zilliz
+} // namespace cache
+} // namespace milvus
+} // namespace zilliz
 
diff --git a/cpp/src/main.cpp b/cpp/src/main.cpp
index ca3283f4d08f0161049c5aae78e7deb51627fc55..22c282d4ea0f4150dfa406a3ae37a0730844c823 100644
--- a/cpp/src/main.cpp
+++ b/cpp/src/main.cpp
@@ -76,7 +76,6 @@ main(int argc, char *argv[]) {
                 std::cout << "Initial log config from: " << log_config_file << std::endl;
                 break;
             }
-
             case 'p': {
                 char *pid_filename_ptr = strdup(optarg);
                 pid_filename = pid_filename_ptr;
@@ -84,7 +83,6 @@ main(int argc, char *argv[]) {
                 std::cout << pid_filename << std::endl;
                 break;
             }
-
             case 'd':
                 start_daemonized = 1;
                 break;
diff --git a/cpp/src/sdk/examples/grpcsimple/main.cpp b/cpp/src/sdk/examples/grpcsimple/main.cpp
index 4de060590c9bb76d837ccac90ff3e7829eb3c366..166707259a46849b672abb0bba17153f2f405737 100644
--- a/cpp/src/sdk/examples/grpcsimple/main.cpp
+++ b/cpp/src/sdk/examples/grpcsimple/main.cpp
@@ -23,8 +23,8 @@
 
 #include "src/ClientTest.h"
 
-void print_help(const std::string &app_name);
-
+void
+print_help(const std::string &app_name);
 
 int
 main(int argc, char *argv[]) {
@@ -56,8 +56,7 @@ main(int argc, char *argv[]) {
                 break;
             }
             case 'h':
-            default:
-                print_help(app_name);
+            default:print_help(app_name);
                 return EXIT_SUCCESS;
         }
     }
@@ -77,4 +76,4 @@ print_help(const std::string &app_name) {
     printf("   -p --port     Server port, default 19530\n");
     printf("   -h --help     Print help information\n");
     printf("\n");
-}
\ No newline at end of file
+}
diff --git a/cpp/src/sdk/examples/grpcsimple/src/ClientTest.cpp b/cpp/src/sdk/examples/grpcsimple/src/ClientTest.cpp
index 16fc2ee16883bc599646481d5d96b751a82d71a3..e29bcc30f380b41e2303bacf6bf6ea4d3245e372 100644
--- a/cpp/src/sdk/examples/grpcsimple/src/ClientTest.cpp
+++ b/cpp/src/sdk/examples/grpcsimple/src/ClientTest.cpp
@@ -15,7 +15,7 @@
 // specific language governing permissions and limitations
 // under the License.
 
-#include "ClientTest.h"
+#include "sdk/examples/grpcsimple/src/ClientTest.h"
 #include "MilvusApi.h"
 #include "cache/CpuCacheMgr.h"
 
@@ -24,15 +24,17 @@
 #include <chrono>
 #include <thread>
 #include <unistd.h>
-
-using namespace milvus;
+#include <memory>
+#include <vector>
+#include <utility>
 
 //#define SET_VECTOR_IDS;
 
 namespace {
-std::string GetTableName();
+const std::string&
+GetTableName();
 
-const std::string TABLE_NAME = GetTableName();
+const char* TABLE_NAME = GetTableName().c_str();
 constexpr int64_t TABLE_DIMENSION = 512;
 constexpr int64_t TABLE_INDEX_FILE_SIZE = 1024;
 constexpr int64_t BATCH_ROW_COUNT = 100000;
@@ -44,26 +46,28 @@ constexpr int64_t SECONDS_EACH_HOUR = 3600;
 
 #define BLOCK_SPLITER std::cout << "===========================================" << std::endl;
 
-void PrintTableSchema(const TableSchema& tb_schema) {
+void
+PrintTableSchema(const milvus::TableSchema &tb_schema) {
     BLOCK_SPLITER
     std::cout << "Table name: " << tb_schema.table_name << std::endl;
     std::cout << "Table dimension: " << tb_schema.dimension << std::endl;
     BLOCK_SPLITER
 }
 
-void PrintSearchResult(const std::vector<std::pair<int64_t, RowRecord>>& search_record_array,
-                       const std::vector<TopKQueryResult>& topk_query_result_array) {
+void
+PrintSearchResult(const std::vector<std::pair<int64_t, milvus::RowRecord>> &search_record_array,
+                  const std::vector<milvus::TopKQueryResult> &topk_query_result_array) {
     BLOCK_SPLITER
     std::cout << "Returned result count: " << topk_query_result_array.size() << std::endl;
 
     int32_t index = 0;
-    for(auto& result : topk_query_result_array) {
+    for (auto &result : topk_query_result_array) {
         auto search_id = search_record_array[index].first;
         index++;
         std::cout << "No." << std::to_string(index) << " vector " << std::to_string(search_id)
                   << " top " << std::to_string(result.query_result_arrays.size())
                   << " search result:" << std::endl;
-        for(auto& item : result.query_result_arrays) {
+        for (auto &item : result.query_result_arrays) {
             std::cout << "\t" << std::to_string(item.id) << "\tdistance:" << std::to_string(item.distance);
             std::cout << std::endl;
         }
@@ -72,80 +76,88 @@ void PrintSearchResult(const std::vector<std::pair<int64_t, RowRecord>>& search_
     BLOCK_SPLITER
 }
 
-std::string CurrentTime() {
+std::string
+CurrentTime() {
     time_t tt;
-    time( &tt );
-    tt = tt + 8*SECONDS_EACH_HOUR;
-    tm* t= gmtime( &tt );
+    time(&tt);
+    tt = tt + 8 * SECONDS_EACH_HOUR;
+    tm t;
+    gmtime_r(&tt, &t);
 
-    std::string str = std::to_string(t->tm_year + 1900) + "_" + std::to_string(t->tm_mon + 1)
-        + "_" + std::to_string(t->tm_mday) + "_" + std::to_string(t->tm_hour)
-        + "_" + std::to_string(t->tm_min) + "_" + std::to_string(t->tm_sec);
+    std::string str = std::to_string(t.tm_year + 1900) + "_" + std::to_string(t.tm_mon + 1)
+        + "_" + std::to_string(t.tm_mday) + "_" + std::to_string(t.tm_hour)
+        + "_" + std::to_string(t.tm_min) + "_" + std::to_string(t.tm_sec);
 
     return str;
 }
 
-std::string CurrentTmDate(int64_t offset_day = 0) {
+std::string
+CurrentTmDate(int64_t offset_day = 0) {
     time_t tt;
-    time( &tt );
-    tt = tt + 8*SECONDS_EACH_HOUR;
-    tt = tt + 24*SECONDS_EACH_HOUR*offset_day;
-    tm* t= gmtime( &tt );
+    time(&tt);
+    tt = tt + 8 * SECONDS_EACH_HOUR;
+    tt = tt + 24 * SECONDS_EACH_HOUR * offset_day;
+    tm t;
+    gmtime_r(&tt, &t);
 
-    std::string str = std::to_string(t->tm_year + 1900) + "-" + std::to_string(t->tm_mon + 1)
-        + "-" + std::to_string(t->tm_mday);
+    std::string str = std::to_string(t.tm_year + 1900) + "-" + std::to_string(t.tm_mon + 1)
+        + "-" + std::to_string(t.tm_mday);
 
     return str;
 }
 
-std::string GetTableName() {
-    static std::string s_id(CurrentTime());
-    return "tbl_" + s_id;
+const std::string&
+GetTableName() {
+    static std::string s_id("tbl_" + CurrentTime());
+    return s_id;
 }
 
-TableSchema BuildTableSchema() {
-    TableSchema tb_schema;
+milvus::TableSchema
+BuildTableSchema() {
+    milvus::TableSchema tb_schema;
     tb_schema.table_name = TABLE_NAME;
     tb_schema.dimension = TABLE_DIMENSION;
     tb_schema.index_file_size = TABLE_INDEX_FILE_SIZE;
-    tb_schema.metric_type = MetricType::L2;
+    tb_schema.metric_type = milvus::MetricType::L2;
 
     return tb_schema;
 }
 
-void BuildVectors(int64_t from, int64_t to,
-                  std::vector<RowRecord>& vector_record_array) {
-    if(to <= from){
+void
+BuildVectors(int64_t from, int64_t to,
+             std::vector<milvus::RowRecord> &vector_record_array) {
+    if (to <= from) {
         return;
     }
 
     vector_record_array.clear();
     for (int64_t k = from; k < to; k++) {
-        RowRecord record;
+        milvus::RowRecord record;
         record.data.resize(TABLE_DIMENSION);
-        for(int64_t i = 0; i < TABLE_DIMENSION; i++) {
-            record.data[i] = (float)(k%(i+1));
+        for (int64_t i = 0; i < TABLE_DIMENSION; i++) {
+            record.data[i] = (float) (k % (i + 1));
         }
 
         vector_record_array.emplace_back(record);
     }
 }
 
-void Sleep(int seconds) {
+void
+Sleep(int seconds) {
     std::cout << "Waiting " << seconds << " seconds ..." << std::endl;
     sleep(seconds);
 }
 
 class TimeRecorder {
  public:
-    explicit TimeRecorder(const std::string& title)
+    explicit TimeRecorder(const std::string &title)
         : title_(title) {
         start_ = std::chrono::system_clock::now();
     }
 
     ~TimeRecorder() {
         std::chrono::system_clock::time_point end = std::chrono::system_clock::now();
-        long span = (std::chrono::duration_cast<std::chrono::milliseconds> (end - start_)).count();
+        int64_t span = (std::chrono::duration_cast<std::chrono::milliseconds>(end - start_)).count();
         std::cout << title_ << " totally cost: " << span << " ms" << std::endl;
     }
 
@@ -154,14 +166,15 @@ class TimeRecorder {
     std::chrono::system_clock::time_point start_;
 };
 
-void CheckResult(const std::vector<std::pair<int64_t, RowRecord>>& search_record_array,
-                 const std::vector<TopKQueryResult>& topk_query_result_array) {
+void
+CheckResult(const std::vector<std::pair<int64_t, milvus::RowRecord>> &search_record_array,
+            const std::vector<milvus::TopKQueryResult> &topk_query_result_array) {
     BLOCK_SPLITER
     int64_t index = 0;
-    for(auto& result : topk_query_result_array) {
+    for (auto &result : topk_query_result_array) {
         auto result_id = result.query_result_arrays[0].id;
         auto search_id = search_record_array[index++].first;
-        if(result_id != search_id) {
+        if (result_id != search_id) {
             std::cout << "The top 1 result is wrong: " << result_id
                       << " vs. " << search_id << std::endl;
         } else {
@@ -171,42 +184,45 @@ void CheckResult(const std::vector<std::pair<int64_t, RowRecord>>& search_record
     BLOCK_SPLITER
 }
 
-void DoSearch(std::shared_ptr<Connection> conn,
-              const std::vector<std::pair<int64_t, RowRecord>>& search_record_array,
-              const std::string& phase_name) {
-    std::vector<Range> query_range_array;
-    Range rg;
+void
+DoSearch(std::shared_ptr<milvus::Connection> conn,
+         const std::vector<std::pair<int64_t, milvus::RowRecord>> &search_record_array,
+         const std::string &phase_name) {
+    std::vector<milvus::Range> query_range_array;
+    milvus::Range rg;
     rg.start_value = CurrentTmDate();
     rg.end_value = CurrentTmDate(1);
     query_range_array.emplace_back(rg);
 
-    std::vector<RowRecord> record_array;
-    for(auto& pair : search_record_array) {
+    std::vector<milvus::RowRecord> record_array;
+    for (auto &pair : search_record_array) {
         record_array.push_back(pair.second);
     }
 
     auto start = std::chrono::high_resolution_clock::now();
-    std::vector<TopKQueryResult> topk_query_result_array;
+    std::vector<milvus::TopKQueryResult> topk_query_result_array;
     {
         TimeRecorder rc(phase_name);
-        Status stat = conn->Search(TABLE_NAME, record_array, query_range_array, TOP_K, 32, topk_query_result_array);
+        milvus::Status stat =
+            conn->Search(TABLE_NAME, record_array, query_range_array, TOP_K, 32, topk_query_result_array);
         std::cout << "SearchVector function call status: " << stat.message() << std::endl;
     }
     auto finish = std::chrono::high_resolution_clock::now();
-    std::cout << "SEARCHVECTOR COST: " << std::chrono::duration_cast<std::chrono::duration<double>>(finish - start).count() << "s\n";
+    std::cout << "SEARCHVECTOR COST: "
+              << std::chrono::duration_cast<std::chrono::duration<double>>(finish - start).count() << "s\n";
 
     PrintSearchResult(search_record_array, topk_query_result_array);
     CheckResult(search_record_array, topk_query_result_array);
 }
-}
+} // namespace
 
 void
-ClientTest::Test(const std::string& address, const std::string& port) {
-    std::shared_ptr<Connection> conn = Connection::Create();
+ClientTest::Test(const std::string &address, const std::string &port) {
+    std::shared_ptr<milvus::Connection> conn = milvus::Connection::Create();
 
     {//connect server
-        ConnectParam param = {address, port};
-        Status stat = conn->Connect(param);
+        milvus::ConnectParam param = {address, port};
+        milvus::Status stat = conn->Connect(param);
         std::cout << "Connect function call status: " << stat.message() << std::endl;
     }
 
@@ -222,10 +238,10 @@ ClientTest::Test(const std::string& address, const std::string& port) {
 
     {
         std::vector<std::string> tables;
-        Status stat = conn->ShowTables(tables);
+        milvus::Status stat = conn->ShowTables(tables);
         std::cout << "ShowTables function call status: " << stat.message() << std::endl;
         std::cout << "All tables: " << std::endl;
-        for(auto& table : tables) {
+        for (auto &table : tables) {
             int64_t row_count = 0;
 //            conn->DropTable(table);
             stat = conn->CountTable(table, row_count);
@@ -234,28 +250,28 @@ ClientTest::Test(const std::string& address, const std::string& port) {
     }
 
     {//create table
-        TableSchema tb_schema = BuildTableSchema();
-        Status stat = conn->CreateTable(tb_schema);
+        milvus::TableSchema tb_schema = BuildTableSchema();
+        milvus::Status stat = conn->CreateTable(tb_schema);
         std::cout << "CreateTable function call status: " << stat.message() << std::endl;
         PrintTableSchema(tb_schema);
 
         bool has_table = conn->HasTable(tb_schema.table_name);
-        if(has_table) {
+        if (has_table) {
             std::cout << "Table is created" << std::endl;
         }
     }
 
     {//describe table
-        TableSchema tb_schema;
-        Status stat = conn->DescribeTable(TABLE_NAME, tb_schema);
+        milvus::TableSchema tb_schema;
+        milvus::Status stat = conn->DescribeTable(TABLE_NAME, tb_schema);
         std::cout << "DescribeTable function call status: " << stat.message() << std::endl;
         PrintTableSchema(tb_schema);
     }
 
-    std::vector<std::pair<int64_t, RowRecord>> search_record_array;
+    std::vector<std::pair<int64_t, milvus::RowRecord>> search_record_array;
     {//insert vectors
         for (int i = 0; i < ADD_VECTOR_LOOP; i++) {//add vectors
-            std::vector<RowRecord> record_array;
+            std::vector<milvus::RowRecord> record_array;
             int64_t begin_index = i * BATCH_ROW_COUNT;
             BuildVectors(begin_index, begin_index + BATCH_ROW_COUNT, record_array);
 
@@ -268,21 +284,21 @@ ClientTest::Test(const std::string& address, const std::string& port) {
 
             std::vector<int64_t> record_ids;
             //generate user defined ids
-            for(int k = 0; k < BATCH_ROW_COUNT; k++) {
-                record_ids.push_back(i*BATCH_ROW_COUNT+k);
+            for (int k = 0; k < BATCH_ROW_COUNT; k++) {
+                record_ids.push_back(i * BATCH_ROW_COUNT + k);
             }
 
             auto start = std::chrono::high_resolution_clock::now();
 
-            Status stat = conn->Insert(TABLE_NAME, record_array, record_ids);
+            milvus::Status stat = conn->Insert(TABLE_NAME, record_array, record_ids);
             auto finish = std::chrono::high_resolution_clock::now();
-            std::cout << "InsertVector cost: " << std::chrono::duration_cast<std::chrono::duration<double>>(finish - start).count() << "s\n";
-
+            std::cout << "InsertVector cost: "
+                      << std::chrono::duration_cast<std::chrono::duration<double>>(finish - start).count() << "s\n";
 
             std::cout << "InsertVector function call status: " << stat.message() << std::endl;
             std::cout << "Returned id array count: " << record_ids.size() << std::endl;
 
-            if(search_record_array.size() < NQ) {
+            if (search_record_array.size() < NQ) {
                 search_record_array.push_back(
                     std::make_pair(record_ids[SEARCH_TARGET], record_array[SEARCH_TARGET]));
             }
@@ -293,27 +309,27 @@ ClientTest::Test(const std::string& address, const std::string& port) {
         Sleep(2);
 
         int64_t row_count = 0;
-        Status stat = conn->CountTable(TABLE_NAME, row_count);
+        milvus::Status stat = conn->CountTable(TABLE_NAME, row_count);
         std::cout << TABLE_NAME << "(" << row_count << " rows)" << std::endl;
 //        DoSearch(conn, search_record_array, "Search without index");
     }
 
     {//wait unit build index finish
         std::cout << "Wait until create all index done" << std::endl;
-        IndexParam index;
+        milvus::IndexParam index;
         index.table_name = TABLE_NAME;
-        index.index_type = IndexType::gpu_ivfsq8;
+        index.index_type = milvus::IndexType::gpu_ivfsq8;
         index.nlist = 16384;
-        Status stat = conn->CreateIndex(index);
+        milvus::Status stat = conn->CreateIndex(index);
         std::cout << "CreateIndex function call status: " << stat.message() << std::endl;
 
-        IndexParam index2;
+        milvus::IndexParam index2;
         stat = conn->DescribeIndex(TABLE_NAME, index2);
         std::cout << "DescribeIndex function call status: " << stat.message() << std::endl;
     }
 
     {//preload table
-        Status stat = conn->PreloadTable(TABLE_NAME);
+        milvus::Status stat = conn->PreloadTable(TABLE_NAME);
         std::cout << "PreloadTable function call status: " << stat.message() << std::endl;
     }
 
@@ -325,7 +341,7 @@ ClientTest::Test(const std::string& address, const std::string& port) {
     }
 
     {//delete index
-        Status stat = conn->DropIndex(TABLE_NAME);
+        milvus::Status stat = conn->DropIndex(TABLE_NAME);
         std::cout << "DropIndex function call status: " << stat.message() << std::endl;
 
         int64_t row_count = 0;
@@ -334,11 +350,11 @@ ClientTest::Test(const std::string& address, const std::string& port) {
     }
 
     {//delete by range
-        Range rg;
+        milvus::Range rg;
         rg.start_value = CurrentTmDate(-2);
         rg.end_value = CurrentTmDate(-3);
 
-        Status stat = conn->DeleteByRange(rg, TABLE_NAME);
+        milvus::Status stat = conn->DeleteByRange(rg, TABLE_NAME);
         std::cout << "DeleteByRange function call status: " << stat.message() << std::endl;
     }
 
@@ -351,7 +367,7 @@ ClientTest::Test(const std::string& address, const std::string& port) {
         std::string status = conn->ServerStatus();
         std::cout << "Server status before disconnect: " << status << std::endl;
     }
-    Connection::Destroy(conn);
+    milvus::Connection::Destroy(conn);
     {//server status
         std::string status = conn->ServerStatus();
         std::cout << "Server status after disconnect: " << status << std::endl;
diff --git a/cpp/src/sdk/examples/grpcsimple/src/ClientTest.h b/cpp/src/sdk/examples/grpcsimple/src/ClientTest.h
index d95897927e546ed89c5163dd98f3800c3353154f..165c36a180efabd8476353a3dd0bb92fa3417d25 100644
--- a/cpp/src/sdk/examples/grpcsimple/src/ClientTest.h
+++ b/cpp/src/sdk/examples/grpcsimple/src/ClientTest.h
@@ -20,6 +20,6 @@
 #include <string>
 
 class ClientTest {
-public:
-    void Test(const std::string& address, const std::string& port);
-};
\ No newline at end of file
+ public:
+    void Test(const std::string &address, const std::string &port);
+};
diff --git a/cpp/src/sdk/grpc/ClientProxy.cpp b/cpp/src/sdk/grpc/ClientProxy.cpp
index 3bcfd699fe6dc65d6c45b502f5287f6453aa7bd5..f4cd1e9a38bf30306cdb49cc22e58022795df150 100644
--- a/cpp/src/sdk/grpc/ClientProxy.cpp
+++ b/cpp/src/sdk/grpc/ClientProxy.cpp
@@ -15,16 +15,20 @@
 // specific language governing permissions and limitations
 // under the License.
 
-#include "ClientProxy.h"
-#include "version.h"
-#include "milvus.grpc.pb.h"
+#include "sdk/grpc/ClientProxy.h"
+#include "../../../version.h"
+#include "grpc/gen-milvus/milvus.grpc.pb.h"
+
+#include <memory>
+#include <vector>
+#include <string>
+
 //#define GRPC_MULTIPLE_THREAD;
 
 namespace milvus {
-
 bool
 UriCheck(const std::string &uri) {
-     size_t index = uri.find_first_of(':', 0);
+    size_t index = uri.find_first_of(':', 0);
     if (index == std::string::npos) {
         return false;
     } else {
@@ -79,7 +83,7 @@ ClientProxy::Disconnect() {
         connected_ = false;
         channel_.reset();
         return status;
-    }catch (std::exception &ex) {
+    } catch (std::exception &ex) {
         return Status(StatusCode::UnknownError, "failed to disconnect: " + std::string(ex.what()));
     }
 }
@@ -96,7 +100,7 @@ ClientProxy::CreateTable(const TableSchema &param) {
         schema.set_table_name(param.table_name);
         schema.set_dimension(param.dimension);
         schema.set_index_file_size(param.index_file_size);
-        schema.set_metric_type((int32_t)param.metric_type);
+        schema.set_metric_type((int32_t) param.metric_type);
 
         return client_ptr_->CreateTable(schema);
     } catch (std::exception &ex) {
@@ -127,13 +131,12 @@ ClientProxy::DropTable(const std::string &table_name) {
 Status
 ClientProxy::CreateIndex(const IndexParam &index_param) {
     try {
-        //TODO:add index params
+        //TODO: add index params
         ::milvus::grpc::IndexParam grpc_index_param;
         grpc_index_param.set_table_name(index_param.table_name);
-        grpc_index_param.mutable_index()->set_index_type((int32_t)index_param.index_type);
+        grpc_index_param.mutable_index()->set_index_type((int32_t) index_param.index_type);
         grpc_index_param.mutable_index()->set_nlist(index_param.nlist);
         return client_ptr_->CreateIndex(grpc_index_param);
-
     } catch (std::exception &ex) {
         return Status(StatusCode::UnknownError, "failed to build index: " + std::string(ex.what()));
     }
@@ -141,8 +144,8 @@ ClientProxy::CreateIndex(const IndexParam &index_param) {
 
 Status
 ClientProxy::Insert(const std::string &table_name,
-                          const std::vector<RowRecord> &record_array,
-                          std::vector<int64_t> &id_array) {
+                    const std::vector<RowRecord> &record_array,
+                    std::vector<int64_t> &id_array) {
     Status status = Status::OK();
     try {
 ////////////////////////////////////////////////////////////////////////////
@@ -181,7 +184,9 @@ ClientProxy::Insert(const std::string &table_name,
         }
         std::for_each(threads.begin(), threads.end(), std::mem_fn(&std::thread::join));
         auto finish = std::chrono::high_resolution_clock::now();
-        std::cout << "InsertVector cost: " << std::chrono::duration_cast<std::chrono::duration<double>>(finish - start).count() << "s\n";
+        std::cout <<
+        "InsertVector cost: " << std::chrono::duration_cast<std::chrono::duration<double>>(finish - start).count()
+        << "s\n";
         std::cout << "*****************************************************\n";
 
         for (size_t i = 0; i < thread_count; i++) {
@@ -213,9 +218,7 @@ ClientProxy::Insert(const std::string &table_name,
                 id_array.push_back(vector_ids.vector_id_array(i));
             }
         }
-
 #endif
-
     } catch (std::exception &ex) {
         return Status(StatusCode::UnknownError, "fail to add vector: " + std::string(ex.what()));
     }
@@ -225,11 +228,11 @@ ClientProxy::Insert(const std::string &table_name,
 
 Status
 ClientProxy::Search(const std::string &table_name,
-                          const std::vector<RowRecord> &query_record_array,
-                          const std::vector<Range> &query_range_array,
-                          int64_t topk,
-                          int64_t nprobe,
-                          std::vector<TopKQueryResult> &topk_query_result_array) {
+                    const std::vector<RowRecord> &query_record_array,
+                    const std::vector<Range> &query_range_array,
+                    int64_t topk,
+                    int64_t nprobe,
+                    std::vector<TopKQueryResult> &topk_query_result_array) {
     try {
         //step 1: convert vectors data
         ::milvus::grpc::SearchParam search_param;
@@ -267,11 +270,9 @@ ClientProxy::Search(const std::string &table_name,
             topk_query_result_array.emplace_back(result);
         }
         return status;
-
     } catch (std::exception &ex) {
         return Status(StatusCode::UnknownError, "fail to search vectors: " + std::string(ex.what()));
     }
-
 }
 
 Status
@@ -284,13 +285,12 @@ ClientProxy::DescribeTable(const std::string &table_name, TableSchema &table_sch
         table_schema.table_name = grpc_schema.table_name();
         table_schema.dimension = grpc_schema.dimension();
         table_schema.index_file_size = grpc_schema.index_file_size();
-        table_schema.metric_type = (MetricType)grpc_schema.metric_type();
+        table_schema.metric_type = (MetricType) grpc_schema.metric_type();
 
         return status;
     } catch (std::exception &ex) {
         return Status(StatusCode::UnknownError, "fail to describe table: " + std::string(ex.what()));
     }
-
 }
 
 Status
@@ -316,7 +316,6 @@ ClientProxy::ShowTables(std::vector<std::string> &table_array) {
             table_array[i] = table_name_list.table_names(i);
         }
         return status;
-
     } catch (std::exception &ex) {
         return Status(StatusCode::UnknownError, "fail to show tables: " + std::string(ex.what()));
     }
@@ -396,11 +395,10 @@ ClientProxy::DescribeIndex(const std::string &table_name, IndexParam &index_para
         grpc_table_name.set_table_name(table_name);
         ::milvus::grpc::IndexParam grpc_index_param;
         Status status = client_ptr_->DescribeIndex(grpc_table_name, grpc_index_param);
-        index_param.index_type = (IndexType)(grpc_index_param.mutable_index()->index_type());
+        index_param.index_type = (IndexType) (grpc_index_param.mutable_index()->index_type());
         index_param.nlist = grpc_index_param.mutable_index()->nlist();
 
         return status;
-
     } catch (std::exception &ex) {
         return Status(StatusCode::UnknownError, "fail to describe index: " + std::string(ex.what()));
     }
@@ -418,4 +416,4 @@ ClientProxy::DropIndex(const std::string &table_name) const {
     }
 }
 
-}
+} // namespace milvus
diff --git a/cpp/src/sdk/grpc/ClientProxy.h b/cpp/src/sdk/grpc/ClientProxy.h
index c3f79d7209b4a0ee1fc0d37934e5dc70c3e07f73..044ce44847d1e8c27b6e50482cc4b05e2431e877 100644
--- a/cpp/src/sdk/grpc/ClientProxy.h
+++ b/cpp/src/sdk/grpc/ClientProxy.h
@@ -20,88 +20,92 @@
 #include "MilvusApi.h"
 #include "GrpcClient.h"
 
+#include <vector>
+#include <string>
+#include <memory>
+
 namespace milvus {
 
 class ClientProxy : public Connection {
-public:
+ public:
     // Implementations of the Connection interface
-    virtual Status
+    Status
     Connect(const ConnectParam &param) override;
 
-    virtual Status
+    Status
     Connect(const std::string &uri) override;
 
-    virtual Status
+    Status
     Connected() const override;
 
-    virtual Status
+    Status
     Disconnect() override;
 
-    virtual Status
+    Status
     CreateTable(const TableSchema &param) override;
 
-    virtual bool
+    bool
     HasTable(const std::string &table_name) override;
 
-    virtual Status
+    Status
     DropTable(const std::string &table_name) override;
 
-    virtual Status
+    Status
     CreateIndex(const IndexParam &index_param) override;
 
-    virtual Status
+    Status
     Insert(const std::string &table_name,
-                    const std::vector<RowRecord> &record_array,
-                    std::vector<int64_t> &id_array) override;
+           const std::vector<RowRecord> &record_array,
+           std::vector<int64_t> &id_array) override;
 
-    virtual Status
+    Status
     Search(const std::string &table_name,
-                    const std::vector<RowRecord> &query_record_array,
-                    const std::vector<Range> &query_range_array,
-                    int64_t topk,
-                    int64_t nprobe,
-                    std::vector<TopKQueryResult> &topk_query_result_array) override;
+           const std::vector<RowRecord> &query_record_array,
+           const std::vector<Range> &query_range_array,
+           int64_t topk,
+           int64_t nprobe,
+           std::vector<TopKQueryResult> &topk_query_result_array) override;
 
-    virtual Status
+    Status
     DescribeTable(const std::string &table_name, TableSchema &table_schema) override;
 
-    virtual Status
+    Status
     CountTable(const std::string &table_name, int64_t &row_count) override;
 
-    virtual Status
+    Status
     ShowTables(std::vector<std::string> &table_array) override;
 
-    virtual std::string
+    std::string
     ClientVersion() const override;
 
-    virtual std::string
+    std::string
     ServerVersion() const override;
 
-    virtual std::string
+    std::string
     ServerStatus() const override;
 
-    virtual std::string
+    std::string
     DumpTaskTables() const override;
 
-    virtual Status
+    Status
     DeleteByRange(Range &range,
                   const std::string &table_name) override;
 
-    virtual Status
+    Status
     PreloadTable(const std::string &table_name) const override;
 
-    virtual Status
+    Status
     DescribeIndex(const std::string &table_name, IndexParam &index_param) const override;
 
-    virtual Status
+    Status
     DropIndex(const std::string &table_name) const override;
 
-private:
+ private:
     std::shared_ptr<::grpc::Channel> channel_;
 
-private:
+ private:
     std::shared_ptr<GrpcClient> client_ptr_;
     bool connected_ = false;
 };
 
-}
+} // namespace milvus
diff --git a/cpp/src/sdk/grpc/GrpcClient.cpp b/cpp/src/sdk/grpc/GrpcClient.cpp
index 67bb85da8ef2d37d324fb006ca3cf4375d01107f..df86f0a3e7402bb05be25956287a2821ef9fbbef 100644
--- a/cpp/src/sdk/grpc/GrpcClient.cpp
+++ b/cpp/src/sdk/grpc/GrpcClient.cpp
@@ -15,13 +15,17 @@
 // specific language governing permissions and limitations
 // under the License.
 
+#include "sdk/grpc/GrpcClient.h"
+
 #include <grpc/grpc.h>
 #include <grpcpp/channel.h>
 #include <grpcpp/client_context.h>
 #include <grpcpp/create_channel.h>
 #include <grpcpp/security/credentials.h>
 
-#include "GrpcClient.h"
+#include <vector>
+#include <string>
+#include <memory>
 
 using grpc::Channel;
 using grpc::ClientContext;
@@ -31,15 +35,14 @@ using grpc::ClientWriter;
 using grpc::Status;
 
 namespace milvus {
-GrpcClient::GrpcClient(std::shared_ptr<::grpc::Channel>& channel)
-        : stub_(::milvus::grpc::MilvusService::NewStub(channel)) {
-
+GrpcClient::GrpcClient(std::shared_ptr<::grpc::Channel> &channel)
+    : stub_(::milvus::grpc::MilvusService::NewStub(channel)) {
 }
 
 GrpcClient::~GrpcClient() = default;
 
 Status
-GrpcClient::CreateTable(const ::milvus::grpc::TableSchema& table_schema) {
+GrpcClient::CreateTable(const ::milvus::grpc::TableSchema &table_schema) {
     ClientContext context;
     grpc::Status response;
     ::grpc::Status grpc_status = stub_->CreateTable(&context, table_schema, &response);
@@ -57,8 +60,8 @@ GrpcClient::CreateTable(const ::milvus::grpc::TableSchema& table_schema) {
 }
 
 bool
-GrpcClient::HasTable(const ::milvus::grpc::TableName& table_name,
-                     Status& status) {
+GrpcClient::HasTable(const ::milvus::grpc::TableName &table_name,
+                     Status &status) {
     ClientContext context;
     ::milvus::grpc::BoolReply response;
     ::grpc::Status grpc_status = stub_->HasTable(&context, table_name, &response);
@@ -76,7 +79,7 @@ GrpcClient::HasTable(const ::milvus::grpc::TableName& table_name,
 }
 
 Status
-GrpcClient::DropTable(const ::milvus::grpc::TableName& table_name) {
+GrpcClient::DropTable(const ::milvus::grpc::TableName &table_name) {
     ClientContext context;
     grpc::Status response;
     ::grpc::Status grpc_status = stub_->DropTable(&context, table_name, &response);
@@ -94,7 +97,7 @@ GrpcClient::DropTable(const ::milvus::grpc::TableName& table_name) {
 }
 
 Status
-GrpcClient::CreateIndex(const ::milvus::grpc::IndexParam& index_param) {
+GrpcClient::CreateIndex(const ::milvus::grpc::IndexParam &index_param) {
     ClientContext context;
     grpc::Status response;
     ::grpc::Status grpc_status = stub_->CreateIndex(&context, index_param, &response);
@@ -112,9 +115,9 @@ GrpcClient::CreateIndex(const ::milvus::grpc::IndexParam& index_param) {
 }
 
 void
-GrpcClient::Insert(::milvus::grpc::VectorIds& vector_ids,
-                         const ::milvus::grpc::InsertParam& insert_param,
-                         Status& status) {
+GrpcClient::Insert(::milvus::grpc::VectorIds &vector_ids,
+                   const ::milvus::grpc::InsertParam &insert_param,
+                   Status &status) {
     ClientContext context;
     ::grpc::Status grpc_status = stub_->Insert(&context, insert_param, &vector_ids);
 
@@ -133,7 +136,7 @@ GrpcClient::Insert(::milvus::grpc::VectorIds& vector_ids,
 }
 
 Status
-GrpcClient::Search(::milvus::grpc::TopKQueryResultList& topk_query_result_list,
+GrpcClient::Search(::milvus::grpc::TopKQueryResultList &topk_query_result_list,
                    const ::milvus::grpc::SearchParam &search_param) {
     ::milvus::grpc::TopKQueryResult query_result;
     ClientContext context;
@@ -154,8 +157,8 @@ GrpcClient::Search(::milvus::grpc::TopKQueryResultList& topk_query_result_list,
 }
 
 Status
-GrpcClient::DescribeTable(::milvus::grpc::TableSchema& grpc_schema,
-                          const std::string& table_name) {
+GrpcClient::DescribeTable(::milvus::grpc::TableSchema &grpc_schema,
+                          const std::string &table_name) {
     ClientContext context;
     ::milvus::grpc::TableName grpc_tablename;
     grpc_tablename.set_table_name(table_name);
@@ -170,14 +173,14 @@ GrpcClient::DescribeTable(::milvus::grpc::TableSchema& grpc_schema,
     if (grpc_schema.status().error_code() != grpc::SUCCESS) {
         std::cerr << grpc_schema.status().reason() << std::endl;
         return Status(StatusCode::ServerFailed,
-            grpc_schema.status().reason());
+                      grpc_schema.status().reason());
     }
 
     return Status::OK();
 }
 
 int64_t
-GrpcClient::CountTable(const std::string& table_name, Status& status) {
+GrpcClient::CountTable(const std::string &table_name, Status &status) {
     ClientContext context;
     ::milvus::grpc::TableRowCount response;
     ::milvus::grpc::TableName grpc_tablename;
@@ -186,7 +189,7 @@ GrpcClient::CountTable(const std::string& table_name, Status& status) {
 
     if (!grpc_status.ok()) {
         std::cerr << "DescribeTable rpc failed!" << std::endl;
-        status = Status(StatusCode::RPCFailed,  grpc_status.error_message());
+        status = Status(StatusCode::RPCFailed, grpc_status.error_message());
         return -1;
     }
 
@@ -223,7 +226,7 @@ GrpcClient::ShowTables(milvus::grpc::TableNameList &table_name_list) {
 
 Status
 GrpcClient::Cmd(std::string &result,
-                 const std::string& cmd) {
+                const std::string &cmd) {
     ClientContext context;
     ::milvus::grpc::StringReply response;
     ::milvus::grpc::Command command;
@@ -321,4 +324,4 @@ GrpcClient::DropIndex(grpc::TableName &table_name) {
     return Status::OK();
 }
 
-}
\ No newline at end of file
+} // namespace milvus
diff --git a/cpp/src/sdk/grpc/GrpcClient.h b/cpp/src/sdk/grpc/GrpcClient.h
index 08714d10e097738646e3b6658b1acae1bf76a50b..8f81e83ae8fb35bbed04ed5bf8105b2c58747e44 100644
--- a/cpp/src/sdk/grpc/GrpcClient.h
+++ b/cpp/src/sdk/grpc/GrpcClient.h
@@ -16,6 +16,11 @@
 // under the License.
 
 #pragma once
+
+#include "MilvusApi.h"
+#include "grpc/gen-milvus/milvus.grpc.pb.h"
+//#include "grpc/gen-status/status.grpc.pb.h"
+
 #include <chrono>
 #include <iostream>
 #include <memory>
@@ -28,55 +33,48 @@
 #include <grpcpp/client_context.h>
 #include <grpcpp/create_channel.h>
 #include <grpcpp/security/credentials.h>
-#include "MilvusApi.h"
-
-#include "milvus.grpc.pb.h"
-//#include "status.grpc.pb.h"
-
-#include <memory>
 
 namespace milvus {
 class GrpcClient {
-public:
-    explicit
-    GrpcClient(std::shared_ptr<::grpc::Channel>& channel);
+ public:
+    explicit GrpcClient(std::shared_ptr<::grpc::Channel> &channel);
 
     virtual
     ~GrpcClient();
 
     Status
-    CreateTable(const grpc::TableSchema& table_schema);
+    CreateTable(const grpc::TableSchema &table_schema);
 
     bool
-    HasTable(const grpc::TableName& table_name, Status& status);
+    HasTable(const grpc::TableName &table_name, Status &status);
 
     Status
-    DropTable(const grpc::TableName& table_name);
+    DropTable(const grpc::TableName &table_name);
 
     Status
-    CreateIndex(const grpc::IndexParam& index_param);
+    CreateIndex(const grpc::IndexParam &index_param);
 
     void
-    Insert(grpc::VectorIds& vector_ids,
-                      const grpc::InsertParam& insert_param,
-                      Status& status);
+    Insert(grpc::VectorIds &vector_ids,
+           const grpc::InsertParam &insert_param,
+           Status &status);
 
     Status
-    Search(::milvus::grpc::TopKQueryResultList& topk_query_result_list,
+    Search(::milvus::grpc::TopKQueryResultList &topk_query_result_list,
            const grpc::SearchParam &search_param);
 
     Status
-    DescribeTable(grpc::TableSchema& grpc_schema,
-                        const std::string& table_name);
+    DescribeTable(grpc::TableSchema &grpc_schema,
+                  const std::string &table_name);
 
     int64_t
-    CountTable(const std::string& table_name, Status& status);
+    CountTable(const std::string &table_name, Status &status);
 
     Status
     ShowTables(milvus::grpc::TableNameList &table_name_list);
 
     Status
-    Cmd(std::string &result, const std::string& cmd);
+    Cmd(std::string &result, const std::string &cmd);
 
     Status
     DeleteByRange(grpc::DeleteByRangeParam &delete_by_range_param);
@@ -93,8 +91,8 @@ public:
     Status
     Disconnect();
 
-private:
+ private:
     std::unique_ptr<grpc::MilvusService::Stub> stub_;
 };
 
-}
+} // namespace milvus
diff --git a/cpp/src/sdk/include/MilvusApi.h b/cpp/src/sdk/include/MilvusApi.h
index 05de495fbc35b574ed419bb2dfaf107b3b7f9421..e6025fd52e541c7c36e612f50c7d483ab901869b 100644
--- a/cpp/src/sdk/include/MilvusApi.h
+++ b/cpp/src/sdk/include/MilvusApi.h
@@ -28,7 +28,6 @@
  */
 namespace milvus {
 
-
 /**
  * @brief Index Type
  */
@@ -108,7 +107,6 @@ struct IndexParam {
  */
 class Connection {
  public:
-
     /**
      * @brief CreateConnection
      *
@@ -131,7 +129,7 @@ class Connection {
      */
 
     static Status
-    Destroy(std::shared_ptr<Connection>& connection_ptr);
+    Destroy(std::shared_ptr<Connection> &connection_ptr);
 
     /**
      * @brief Connect
@@ -180,7 +178,6 @@ class Connection {
     virtual Status
     Disconnect() = 0;
 
-
     /**
      * @brief Create table method
      *
@@ -193,7 +190,6 @@ class Connection {
     virtual Status
     CreateTable(const TableSchema &param) = 0;
 
-
     /**
      * @brief Test table existence method
      *
@@ -206,7 +202,6 @@ class Connection {
     virtual bool
     HasTable(const std::string &table_name) = 0;
 
-
     /**
      * @brief Delete table method
      *
@@ -248,8 +243,8 @@ class Connection {
      */
     virtual Status
     Insert(const std::string &table_name,
-                 const std::vector<RowRecord> &record_array,
-                 std::vector<int64_t> &id_array) = 0;
+           const std::vector<RowRecord> &record_array,
+           std::vector<int64_t> &id_array) = 0;
 
     /**
      * @brief Search vector
@@ -266,11 +261,11 @@ class Connection {
      */
     virtual Status
     Search(const std::string &table_name,
-                 const std::vector<RowRecord> &query_record_array,
-                 const std::vector<Range> &query_range_array,
-                 int64_t topk,
-                 int64_t nprobe,
-                 std::vector<TopKQueryResult> &topk_query_result_array) = 0;
+           const std::vector<RowRecord> &query_record_array,
+           const std::vector<Range> &query_range_array,
+           int64_t topk,
+           int64_t nprobe,
+           std::vector<TopKQueryResult> &topk_query_result_array) = 0;
 
     /**
      * @brief Show table description
@@ -297,7 +292,7 @@ class Connection {
      */
     virtual Status
     CountTable(const std::string &table_name,
-            int64_t &row_count) = 0;
+               int64_t &row_count) = 0;
 
     /**
      * @brief Show all tables in database
@@ -395,4 +390,4 @@ class Connection {
     DropIndex(const std::string &table_name) const = 0;
 };
 
-}
\ No newline at end of file
+} // namespace milvus
diff --git a/cpp/src/sdk/include/Status.h b/cpp/src/sdk/include/Status.h
index cdb5f54ede9131fc80c5c05500d246cd5c818d52..670d9662b4a23700fb39d163225a1c5071366acf 100644
--- a/cpp/src/sdk/include/Status.h
+++ b/cpp/src/sdk/include/Status.h
@@ -29,6 +29,7 @@ namespace milvus {
 */
 enum class StatusCode {
     OK = 0,
+
     // system error section
     UnknownError = 1,
     NotSupported,
@@ -44,7 +45,7 @@ enum class StatusCode {
 * @brief Status for SDK interface return
 */
 class Status {
-public:
+ public:
     Status(StatusCode code, const std::string &msg);
     Status();
     ~Status();
@@ -60,28 +61,32 @@ public:
     operator=(Status &&s);
 
     static Status
-    OK() { return Status(); }
+    OK() {
+        return Status();
+    }
 
     bool
-    ok() const { return state_ == nullptr || code() == StatusCode::OK; }
+    ok() const {
+        return state_ == nullptr || code() == StatusCode::OK;
+    }
 
     StatusCode
     code() const {
-        return (state_ == nullptr) ? StatusCode::OK : *(StatusCode*)(state_);
+        return (state_ == nullptr) ? StatusCode::OK : *(StatusCode *) (state_);
     }
 
     std::string
     message() const;
 
-private:
+ private:
     inline void
     CopyFrom(const Status &s);
 
     inline void
     MoveFrom(Status &s);
 
-private:
+ private:
     const char *state_ = nullptr;
 }; // Status
 
-} //Milvus
\ No newline at end of file
+} // namespace milvus
diff --git a/cpp/src/sdk/interface/ConnectionImpl.cpp b/cpp/src/sdk/interface/ConnectionImpl.cpp
index 3730cfd191c01950306f45f7cd7ce185eb596ade..5a01cd1a797bf536ad24d52b70711eeda48da1c9 100644
--- a/cpp/src/sdk/interface/ConnectionImpl.cpp
+++ b/cpp/src/sdk/interface/ConnectionImpl.cpp
@@ -15,7 +15,7 @@
 // specific language governing permissions and limitations
 // under the License.
 
-#include "ConnectionImpl.h"
+#include "sdk/interface/ConnectionImpl.h"
 
 namespace milvus {
 
@@ -25,7 +25,7 @@ Connection::Create() {
 }
 
 Status
-Connection::Destroy(std::shared_ptr<milvus::Connection>& connection_ptr) {
+Connection::Destroy(std::shared_ptr<milvus::Connection> &connection_ptr) {
     if (connection_ptr != nullptr) {
         return connection_ptr->Disconnect();
     }
@@ -84,19 +84,18 @@ ConnectionImpl::CreateIndex(const IndexParam &index_param) {
 
 Status
 ConnectionImpl::Insert(const std::string &table_name,
-                          const std::vector<RowRecord> &record_array,
-                          std::vector<int64_t> &id_array) {
+                       const std::vector<RowRecord> &record_array,
+                       std::vector<int64_t> &id_array) {
     return client_proxy_->Insert(table_name, record_array, id_array);
 }
 
-
 Status
 ConnectionImpl::Search(const std::string &table_name,
-                             const std::vector<RowRecord> &query_record_array,
-                             const std::vector<Range> &query_range_array,
-                             int64_t topk,
-                             int64_t nprobe,
-                             std::vector<TopKQueryResult> &topk_query_result_array) {
+                       const std::vector<RowRecord> &query_record_array,
+                       const std::vector<Range> &query_range_array,
+                       int64_t topk,
+                       int64_t nprobe,
+                       std::vector<TopKQueryResult> &topk_query_result_array) {
     return client_proxy_->Search(table_name, query_record_array, query_range_array, topk,
                                  nprobe, topk_query_result_array);
 }
@@ -133,7 +132,7 @@ ConnectionImpl::DumpTaskTables() const {
 
 Status
 ConnectionImpl::DeleteByRange(Range &range,
-              const std::string &table_name) {
+                              const std::string &table_name) {
     return client_proxy_->DeleteByRange(range, table_name);
 }
 
@@ -143,7 +142,7 @@ ConnectionImpl::PreloadTable(const std::string &table_name) const {
 }
 
 Status
-ConnectionImpl::DescribeIndex(const std::string &table_name, IndexParam& index_param) const {
+ConnectionImpl::DescribeIndex(const std::string &table_name, IndexParam &index_param) const {
     return client_proxy_->DescribeIndex(table_name, index_param);
 }
 
@@ -152,4 +151,4 @@ ConnectionImpl::DropIndex(const std::string &table_name) const {
     return client_proxy_->DropIndex(table_name);
 }
 
-}
+} // namespace milvus
diff --git a/cpp/src/sdk/interface/ConnectionImpl.h b/cpp/src/sdk/interface/ConnectionImpl.h
index 6a402fcb0d8a08cdccecc6f6c93efa92e421a7d9..7d5e09088249b58b74d0d3f90dea822f80d9528b 100644
--- a/cpp/src/sdk/interface/ConnectionImpl.h
+++ b/cpp/src/sdk/interface/ConnectionImpl.h
@@ -18,88 +18,92 @@
 #pragma once
 
 #include "MilvusApi.h"
-#include "src/sdk/grpc/ClientProxy.h"
+#include "sdk/grpc/ClientProxy.h"
+
+#include <vector>
+#include <memory>
+#include <string>
 
 namespace milvus {
 
 class ConnectionImpl : public Connection {
-public:
+ public:
     ConnectionImpl();
 
     // Implementations of the Connection interface
-    virtual Status
+    Status
     Connect(const ConnectParam &param) override;
 
-    virtual Status
+    Status
     Connect(const std::string &uri) override;
 
-    virtual Status
+    Status
     Connected() const override;
 
-    virtual Status
+    Status
     Disconnect() override;
 
-    virtual Status
+    Status
     CreateTable(const TableSchema &param) override;
 
-    virtual
-    bool HasTable(const std::string &table_name) override;
+    bool
+    HasTable(const std::string &table_name) override;
 
-    virtual Status
+    Status
     DropTable(const std::string &table_name) override;
 
-    virtual Status
+    Status
     CreateIndex(const IndexParam &index_param) override;
 
-    virtual Status
+    Status
     Insert(const std::string &table_name,
            const std::vector<RowRecord> &record_array,
            std::vector<int64_t> &id_array) override;
 
-    virtual Status
+    Status
     Search(const std::string &table_name,
-                                const std::vector<RowRecord> &query_record_array,
-                                const std::vector<Range> &query_range_array,
-                                int64_t topk,
-                                int64_t nprobe,
-                                std::vector<TopKQueryResult> &topk_query_result_array) override;
+           const std::vector<RowRecord> &query_record_array,
+           const std::vector<Range> &query_range_array,
+           int64_t topk,
+           int64_t nprobe,
+           std::vector<TopKQueryResult> &topk_query_result_array) override;
 
-    virtual Status
+    Status
     DescribeTable(const std::string &table_name, TableSchema &table_schema) override;
 
-    virtual Status
+    Status
     CountTable(const std::string &table_name, int64_t &row_count) override;
 
-    virtual Status
+    Status
     ShowTables(std::vector<std::string> &table_array) override;
 
-    virtual std::string
+    std::string
     ClientVersion() const override;
 
-    virtual std::string
+    std::string
     ServerVersion() const override;
 
-    virtual std::string
+    std::string
     ServerStatus() const override;
 
-    virtual std::string
+    std::string
     DumpTaskTables() const override;
 
-    virtual Status
+    Status
     DeleteByRange(Range &range,
                   const std::string &table_name) override;
 
-    virtual Status
+    Status
     PreloadTable(const std::string &table_name) const override;
 
-    virtual Status
-    DescribeIndex(const std::string &table_name, IndexParam& index_param) const override;
+    Status
+    DescribeIndex(const std::string &table_name, IndexParam &index_param) const override;
 
-    virtual Status
+    Status
     DropIndex(const std::string &table_name) const override;
 
-private:
+ private:
     std::shared_ptr<ClientProxy> client_proxy_;
 };
 
-}
+} // namespace milvus
diff --git a/cpp/src/sdk/interface/Status.cpp b/cpp/src/sdk/interface/Status.cpp
index e6fd06c72e8db09be76cb4a30919b0e251d01369..a8780f2ddde94e992c5360596ca72c13aff09fa6 100644
--- a/cpp/src/sdk/interface/Status.cpp
+++ b/cpp/src/sdk/interface/Status.cpp
@@ -23,12 +23,12 @@ namespace milvus {
 
 constexpr int CODE_WIDTH = sizeof(StatusCode);
 
-Status::Status(StatusCode code, const std::string& msg) {
+Status::Status(StatusCode code, const std::string &msg) {
     //4 bytes store code
     //4 bytes store message length
     //the left bytes store message string
-    const uint32_t length = (uint32_t)msg.size();
-    char* result = new char[length + sizeof(length) + CODE_WIDTH];
+    const uint32_t length = (uint32_t) msg.size();
+    char *result = new char[length + sizeof(length) + CODE_WIDTH];
     memcpy(result, &code, CODE_WIDTH);
     memcpy(result + CODE_WIDTH, &length, sizeof(length));
     memcpy(result + sizeof(length) + CODE_WIDTH, msg.data(), length);
@@ -37,8 +37,7 @@ Status::Status(StatusCode code, const std::string& msg) {
 }
 
 Status::Status()
-        : state_(nullptr) {
-
+    : state_(nullptr) {
 }
 
 Status::~Status() {
@@ -46,22 +45,22 @@ Status::~Status() {
 }
 
 Status::Status(const Status &s)
-        : state_(nullptr) {
+    : state_(nullptr) {
     CopyFrom(s);
 }
 
-Status&
+Status &
 Status::operator=(const Status &s) {
     CopyFrom(s);
     return *this;
 }
 
 Status::Status(Status &&s)
-        : state_(nullptr) {
+    : state_(nullptr) {
     MoveFrom(s);
 }
 
-Status&
+Status &
 Status::operator=(Status &&s) {
     MoveFrom(s);
     return *this;
@@ -71,7 +70,7 @@ void
 Status::CopyFrom(const Status &s) {
     delete state_;
     state_ = nullptr;
-    if(s.state_ == nullptr) {
+    if (s.state_ == nullptr) {
         return;
     }
 
@@ -79,7 +78,7 @@ Status::CopyFrom(const Status &s) {
     memcpy(&length, s.state_ + CODE_WIDTH, sizeof(length));
     int buff_len = length + sizeof(length) + CODE_WIDTH;
     state_ = new char[buff_len];
-    memcpy((void*)state_, (void*)s.state_, buff_len);
+    memcpy((void *) state_, (void *) s.state_, buff_len);
 }
 
 void
@@ -98,12 +97,13 @@ Status::message() const {
     std::string msg;
     uint32_t length = 0;
     memcpy(&length, state_ + CODE_WIDTH, sizeof(length));
-    if(length > 0) {
+    if (length > 0) {
         msg.append(state_ + sizeof(length) + CODE_WIDTH, length);
     }
 
     return msg;
 }
 
-}
+} // namespace milvus
+