node: add toString()

src/node.cpp

@@ -21,6 +21,8 @@
 
 #include "node.h"
 
+#include <sstream>
+
 namespace dht {
 
 constexpr std::chrono::minutes Node::NODE_EXPIRE_TIME;
@@ -77,6 +79,14 @@ Node::received(time_point now, bool answer)
     }
 }
 
+std::string
+Node::toString() const
+{
+    std::stringstream ss;
+    ss << (*this);
+    return ss.str();
+}
+
 std::ostream& operator<< (std::ostream& s, const Node& h)
 {
     s << h.id << " " << print_addr(h.ss, h.sslen);