Remove type method from GraphDb

Reviewers: msantl, vkasljevic, mferencevic

Reviewed By: msantl

Subscribers: pullbot

Differential Revision: https://phabricator.memgraph.io/D1577

src/database/distributed_graph_db.cpp

@@ -437,10 +437,10 @@ class WorkerAccessor final : public DistributedAccessor {
 // RecoveryTransactions implementations
 //////////////////////////////////////////////////////////////////////
 
-class DistributedRecoveryTransanctions
+class DistributedRecoveryTransactions
     : public durability::RecoveryTransactions {
  public:
-  explicit DistributedRecoveryTransanctions(DistributedGraphDb *db) : db_(db) {}
+  explicit DistributedRecoveryTransactions(DistributedGraphDb *db) : db_(db) {}
 
   void Begin(const tx::TransactionId &tx_id) override {
     CHECK(accessors_.find(tx_id) == accessors_.end())
@@ -463,30 +463,34 @@ class DistributedRecoveryTransanctions
   }
 
  protected:
-  virtual GraphDbAccessor *GetAccessor(const tx::TransactionId &tx_id) {
-    auto found = accessors_.find(tx_id);
-    // Currently accessors are created on transaction_begin, but since workers
-    // don't have a transaction begin, the accessors are not created.
-    if (db_->type() == database::GraphDb::Type::DISTRIBUTED_WORKER &&
-        found == accessors_.end()) {
-      std::tie(found, std::ignore) = accessors_.emplace(tx_id, db_->Access());
-    }
-
-    CHECK(found != accessors_.end())
-        << "Accessor does not exist for transaction: " << tx_id;
-    return found->second.get();
-  }
+  virtual GraphDbAccessor *GetAccessor(const tx::TransactionId &tx_id) = 0;
 
   DistributedGraphDb *db_;
   std::unordered_map<tx::TransactionId, std::unique_ptr<GraphDbAccessor>>
       accessors_;
 };
 
+class MasterRecoveryTransactions final
+    : public DistributedRecoveryTransactions {
+ public:
+  explicit MasterRecoveryTransactions(Master *db)
+      : DistributedRecoveryTransactions(db) {}
+
+ protected:
+  virtual GraphDbAccessor *GetAccessor(
+      const tx::TransactionId &tx_id) override {
+    auto found = accessors_.find(tx_id);
+    CHECK(found != accessors_.end())
+        << "Accessor does not exist for transaction: " << tx_id;
+    return found->second.get();
+  }
+};
+
 class WorkerRecoveryTransactions final
-    : public DistributedRecoveryTransanctions {
+    : public DistributedRecoveryTransactions {
  public:
   explicit WorkerRecoveryTransactions(Worker *db)
-      : DistributedRecoveryTransanctions(db) {}
+      : DistributedRecoveryTransactions(db) {}
 
   void Begin(const tx::TransactionId &tx_id) override {
     LOG(FATAL) << "Unexpected transaction begin on worker recovery.";
@@ -628,7 +632,7 @@ Master::Master(Config config)
       // workers and on master
       recovery_data.wal_tx_to_recover =
           impl_->coordination_.CommonWalTransactions(*recovery_info);
-      DistributedRecoveryTransanctions recovery_transactions(this);
+      MasterRecoveryTransactions recovery_transactions(this);
       durability::RecoverWalAndIndexes(impl_->config_.durability_directory,
                                        this, &recovery_data,
                                        &recovery_transactions);

src/database/distributed_graph_db.hpp

@@ -45,10 +45,6 @@ class Master final : public DistributedGraphDb {
   explicit Master(Config config = Config());
   ~Master();
 
-  GraphDb::Type type() const override {
-    return GraphDb::Type::DISTRIBUTED_MASTER;
-  }
-
   std::unique_ptr<GraphDbAccessor> Access() override;
   std::unique_ptr<GraphDbAccessor> Access(tx::TransactionId) override;
 
@@ -93,10 +89,6 @@ class Worker final : public DistributedGraphDb {
   explicit Worker(Config config = Config());
   ~Worker();
 
-  GraphDb::Type type() const override {
-    return GraphDb::Type::DISTRIBUTED_WORKER;
-  }
-
   std::unique_ptr<GraphDbAccessor> Access() override;
   std::unique_ptr<GraphDbAccessor> Access(tx::TransactionId) override;
 

src/database/graph_db.hpp

@@ -1,3 +1,4 @@
+/// @file
 #pragma once
 
 #include <atomic>
@@ -48,7 +49,7 @@ struct Config {
 
 class GraphDbAccessor;
 
-/// An abstract base class for a SingleNode/Master/Worker graph db.
+/// An abstract base class providing the interface for a graph database.
 ///
 /// Always be sure that GraphDb object is destructed before main exits, i. e.
 /// GraphDb object shouldn't be part of global/static variable, except if its
@@ -71,8 +72,6 @@ class GraphDbAccessor;
 /// -> CRASH
 class GraphDb {
  public:
-  enum class Type { SINGLE_NODE, DISTRIBUTED_MASTER, DISTRIBUTED_WORKER };
-
   GraphDb() {}
   GraphDb(const GraphDb &) = delete;
   GraphDb(GraphDb &&) = delete;
@@ -81,8 +80,6 @@ class GraphDb {
 
   virtual ~GraphDb() {}
 
-  virtual Type type() const = 0;
-
   /// Create a new accessor by starting a new transaction.
   virtual std::unique_ptr<GraphDbAccessor> Access() = 0;
   /// Create an accessor for a running transaction.
@@ -123,8 +120,6 @@ class SingleNode final : public GraphDb {
   explicit SingleNode(Config config = Config());
   ~SingleNode();
 
-  Type type() const override { return GraphDb::Type::SINGLE_NODE; }
-
   std::unique_ptr<GraphDbAccessor> Access() override;
   std::unique_ptr<GraphDbAccessor> Access(tx::TransactionId) override;