add catalog test

src/storage/meta/catalog.cpp

@@ -12,6 +12,10 @@ NewCatalog::NewCatalog(SharedPtr<String> dir)
     : current_dir_(std::move(dir)) {
 }
 
+// do not only use this method to create database
+// it will not record database in transaction, so when you commit transaction
+// it will lost operation
+// use Txn::CreateDatabase instead
 EntryResult
 NewCatalog::CreateDatabase(NewCatalog* catalog,
                            const String& db_name,
@@ -48,6 +52,10 @@ NewCatalog::CreateDatabase(NewCatalog* catalog,
     return res;
 }
 
+// do not only use this method to drop database
+// it will not record database in transaction, so when you commit transaction
+// it will lost operation
+// use Txn::DropDatabase instead
 EntryResult
 NewCatalog::DropDatabase(NewCatalog* catalog,
                          const String& db_name,
@@ -115,8 +123,6 @@ NewCatalog::Databases(NewCatalog* catalog, Txn* txn) {
 
 nlohmann::json
 NewCatalog::Serialize(const NewCatalog* catalog) {
-    SharedPtr<String> current_dir_{nullptr};
-
     nlohmann::json json_res;
 
     json_res["current_dir"] = *catalog->current_dir_;

src/storage/meta/db_meta.cpp

@@ -3,6 +3,7 @@
 //
 
 #include "db_meta.h"
+#include "common/types/internal_types.h"
 #include "main/logger.h"
 #include "common/utility/defer_op.h"
 #include "storage/txn/txn_manager.h"
@@ -33,7 +34,7 @@ DBMeta::CreateNewEntry(DBMeta* db_meta,
         res = db_entry.get();
         db_meta->entry_list_.emplace_front(std::move(db_entry));
 
-//        rw_locker_.unlock();
+
         LOG_TRACE("New database entry is added.");
         return {res, nullptr};
     } else {
@@ -50,8 +51,7 @@ DBMeta::CreateNewEntry(DBMeta* db_meta,
         }
 
         DBEntry* header_db_entry = (DBEntry*)header_base_entry;
-        if(header_db_entry->commit_ts_ < UNCOMMIT_TS) {
-            // Committed
+        if(header_db_entry->Committed()) {
             if(begin_ts > header_db_entry->commit_ts_) {
                 if(header_db_entry->deleted_) {
                     // No conflict
@@ -144,8 +144,7 @@ DBMeta::DropNewEntry(DBMeta* db_meta, u64 txn_id, TxnTimeStamp begin_ts, TxnMana
     }
 
     DBEntry* header_db_entry = (DBEntry*)header_base_entry;
-    if(header_db_entry->commit_ts_ < UNCOMMIT_TS) {
-        // Committed
+    if(header_db_entry->Committed()) {
         if(begin_ts > header_db_entry->commit_ts_) {
             // No conflict
             if(header_db_entry->deleted_) {
@@ -193,7 +192,7 @@ DBMeta::DeleteNewEntry(DBMeta* db_meta, u64 txn_id, TxnManager* txn_mgr) {
 
     auto removed_iter = std::remove_if(db_meta->entry_list_.begin(),
                                        db_meta->entry_list_.end(),
-                                       [&](UniquePtr<BaseEntry>& entry)->bool {
+                                       [&](auto& entry)->bool {
         return entry->txn_id_ == txn_id;
     });
 
@@ -215,8 +214,7 @@ DBMeta::GetEntry(DBMeta* db_meta, u64 txn_id, TxnTimeStamp begin_ts) {
             return {nullptr, MakeUnique<String>("No valid db entry.")};
         }
 
-        if(db_entry->commit_ts_ < UNCOMMIT_TS) {
-            // committed
+        if(db_entry->Committed()) {
             if(begin_ts > db_entry->commit_ts_) {
                 if(db_entry->deleted_) {
                     LOG_TRACE("DB is dropped.")
@@ -226,12 +224,15 @@ DBMeta::GetEntry(DBMeta* db_meta, u64 txn_id, TxnTimeStamp begin_ts) {
                 }
             }
         } else {
-            // Only committed txn is visible. Committing txn isn't visble.
-
-            // not committed, but the same txn is also visible
-            if(txn_id == db_entry->txn_id_) {
-                // same txn
-                return {db_entry.get(), nullptr};
+            // Only committed txn is visible. Committing txn isn't visble,
+            // except same txn is visible
+            if(txn_id == db_entry->txn_id_ ) {
+                if (db_entry->deleted_) {
+                    LOG_TRACE("DB is dropped.")
+                    return {nullptr, MakeUnique<String>("DB is dropped.")};
+                } else {
+                    return {db_entry.get(), nullptr};
+                }
             }
         }
     }

src/storage/meta/entry/base_entry.h

@@ -61,6 +61,21 @@ struct BaseEntry {
 struct EntryResult {
     BaseEntry* entry_;
     UniquePtr<String> err_;
+
+    bool Success() {
+        return err_ == nullptr;
+    }
+
+    bool Fail() {
+        return err_ != nullptr;
+    }
+
+    String ToString() {
+        if(err_ == nullptr) {
+            return "Success";
+        }
+        return *err_.get();
+    }
 };
 
 }

src/storage/txn/txn.h

@@ -116,6 +116,11 @@ class Txn {
         return txn_context_.GetCommitTS();
     }
 
+    inline TxnTimeStamp
+    BeginTS() {
+        return txn_context_.GetBeginTS();
+    }
+
     inline TxnState
     GetTxnState() {
         return txn_context_.GetTxnState();