locator: topology: Add printer

locator/topology.cc

@@ -509,6 +509,18 @@ void topology::for_each_node(std::function<void(const node*)> func) const {
 
 namespace std {
 
+std::ostream& operator<<(std::ostream& out, const locator::topology& t) {
+    out << "{this_host_id: " << t._cfg.this_host_id
+        << ", this_endpoint: " << t._cfg.this_endpoint
+        << ", dc: " << t._cfg.local_dc_rack.dc
+        << ", rack: " << t._cfg.local_dc_rack.rack
+        << ", nodes:\n";
+    for (auto&& node : t._nodes) {
+        out << "  " << locator::topology::debug_format(&*node) << "\n";
+    }
+    return out << "}";
+}
+
 std::ostream& operator<<(std::ostream& out, const locator::node& node) {
     fmt::print(out, "{}", node);
     return out;

locator/topology.hh

@@ -25,8 +25,14 @@
 using namespace seastar;
 
 namespace locator {
-
 class topology;
+}
+
+namespace std {
+std::ostream& operator<<(std::ostream& out, const locator::topology&);
+}
+
+namespace locator {
 
 class node;
 using node_holder = std::unique_ptr<node>;
@@ -315,6 +321,8 @@ private:
     friend class token_metadata_impl;
 public:
     void test_compare_endpoints(const inet_address& address, const inet_address& a1, const inet_address& a2) const;
+
+    friend std::ostream& std::operator<<(std::ostream& out, const topology&);
 };
 
 } // namespace locator