Virtual transaction refresh_if_needed

nano/secure/transaction.hpp

@@ -27,6 +27,9 @@ public:
 
 	// Conversion operator to const nano::store::transaction&
 	virtual operator const nano::store::transaction & () const = 0;
+
+	// Certain transactions may need to be refreshed if they are held for a long time
+	virtual bool refresh_if_needed (std::chrono::milliseconds max_age = std::chrono::milliseconds{ 500 }) = 0;
 };
 
 class write_transaction final : public transaction
@@ -69,7 +72,7 @@ public:
 		renew ();
 	}
 
-	bool refresh_if_needed (std::chrono::milliseconds max_age = std::chrono::milliseconds{ 500 })
+	bool refresh_if_needed (std::chrono::milliseconds max_age = std::chrono::milliseconds{ 500 }) override
 	{
 		auto now = std::chrono::steady_clock::now ();
 		if (now - start > max_age)
@@ -119,9 +122,9 @@ public:
 		txn.refresh ();
 	}
 
-	void refresh_if_needed (std::chrono::milliseconds max_age = std::chrono::milliseconds{ 500 })
+	bool refresh_if_needed (std::chrono::milliseconds max_age = std::chrono::milliseconds{ 500 }) override
 	{
-		txn.refresh_if_needed (max_age);
+		return txn.refresh_if_needed (max_age);
 	}
 
 	auto timestamp () const

nano/store/transaction.cpp

@@ -83,13 +83,15 @@ void nano::store::read_transaction::refresh ()
 	renew ();
 }
 
-void nano::store::read_transaction::refresh_if_needed (std::chrono::milliseconds max_age)
+bool nano::store::read_transaction::refresh_if_needed (std::chrono::milliseconds max_age)
 {
 	auto now = std::chrono::steady_clock::now ();
 	if (now - start > max_age)
 	{
 		refresh ();
+		return true;
 	}
+	return false;
 }
 
 /*

nano/store/transaction.hpp

@@ -66,7 +66,7 @@ public:
 	void reset ();
 	void renew ();
 	void refresh ();
-	void refresh_if_needed (std::chrono::milliseconds max_age = std::chrono::milliseconds{ 500 });
+	bool refresh_if_needed (std::chrono::milliseconds max_age = std::chrono::milliseconds{ 500 });
 
 private:
 	std::unique_ptr<read_transaction_impl> impl;