add gossip info to systemd status

* adds next and last gossip datetimes
* adds a few things for time points, like ostream operator overloads for time point

llarp/router/i_gossiper.hpp

@@ -1,5 +1,7 @@
 #pragma once
 #include <llarp/router_contact.hpp>
+#include <llarp/util/time.hpp>
+#include <optional>
 
 namespace llarp
 {
@@ -15,7 +17,7 @@ namespace llarp
     virtual bool
     GossipRC(const RouterContact& rc) = 0;
 
-    using Time_t = std::chrono::milliseconds;
+    using Time_t = Duration_t;
 
     virtual void
     Decay(Time_t now) = 0;
@@ -31,5 +33,13 @@ namespace llarp
     /// forget the replay filter entry given pubkey
     virtual void
     Forget(const RouterID& router) = 0;
+
+    /// returns the time point when we will send our next gossip at
+    virtual TimePoint_t
+    NextGossipAt() const = 0;
+
+    /// returns the time point when we sent our last gossip at or nullopt if we never did
+    virtual std::optional<TimePoint_t>
+    LastGossipAt() const = 0;
   };
 }  // namespace llarp

llarp/router/rc_gossiper.cpp

@@ -50,6 +50,22 @@ namespace llarp
       m_LastGossipedOurRC = 0s;
   }
 
+  TimePoint_t
+  RCGossiper::NextGossipAt() const
+  {
+    if (auto maybe = LastGossipAt())
+      return *maybe + GossipOurRCInterval;
+    return DateClock_t::now();
+  }
+
+  std::optional<TimePoint_t>
+  RCGossiper::LastGossipAt() const
+  {
+    if (m_LastGossipedOurRC == 0s)
+      return std::nullopt;
+    return DateClock_t::time_point{m_LastGossipedOurRC};
+  }
+
   bool
   RCGossiper::GossipRC(const RouterContact& rc)
   {

llarp/router/rc_gossiper.hpp

@@ -32,6 +32,12 @@ namespace llarp
     void
     Forget(const RouterID& router) override;
 
+    TimePoint_t
+    NextGossipAt() const override;
+
+    std::optional<TimePoint_t>
+    LastGossipAt() const override;
+
    private:
     RouterID m_OurRouterID;
     Time_t m_LastGossipedOurRC = 0s;

llarp/router/router.cpp

@@ -869,7 +869,16 @@ namespace llarp
         ss << " snode | known/svc/clients: " << nodedb()->NumLoaded() << "/"
            << NumberOfConnectedRouters() << "/" << NumberOfConnectedClients() << " | "
            << pathContext().CurrentTransitPaths() << " active paths | "
-           << "block " << (m_lokidRpcClient ? m_lokidRpcClient->BlockHeight() : 0);
+           << "block " << (m_lokidRpcClient ? m_lokidRpcClient->BlockHeight() : 0) << " | gossip: "
+           << "(next/last) " << _rcGossiper.NextGossipAt() << "/";
+        if (auto maybe = _rcGossiper.LastGossipAt())
+        {
+          ss << *maybe;
+        }
+        else
+        {
+          ss << "never";
+        }
       }
       else
       {

llarp/util/time.cpp

@@ -1,20 +1,24 @@
 #include "time.hpp"
 #include <chrono>
+#include <iomanip>
 
 namespace llarp
 {
-  using Clock_t = std::chrono::system_clock;
-
-  template <typename Res, typename Clock>
-  static Duration_t
-  time_since_epoch(std::chrono::time_point<Clock> point)
+  namespace
   {
-    return std::chrono::duration_cast<Res>(point.time_since_epoch());
-  }
+    using Clock_t = std::chrono::system_clock;
+
+    template <typename Res, typename Clock>
+    static Duration_t
+    time_since_epoch(std::chrono::time_point<Clock> point)
+    {
+      return std::chrono::duration_cast<Res>(point.time_since_epoch());
+    }
 
-  const static auto started_at_system = Clock_t::now();
+    const static auto started_at_system = Clock_t::now();
 
-  const static auto started_at_steady = std::chrono::steady_clock::now();
+    const static auto started_at_steady = std::chrono::steady_clock::now();
+  }  // namespace
 
   uint64_t
   ToMS(Duration_t ms)
@@ -74,4 +78,11 @@ namespace llarp
     out.fill(old_fill);
     return out << "s";
   }
+
+  std::ostream&
+  operator<<(std::ostream& out, const TimePoint_t& tp)
+  {
+    auto t = TimePoint_t::clock::to_time_t(tp);
+    return out << std::put_time(std::localtime(&t), "%c %Z");
+  }
 }  // namespace llarp

llarp/util/time.hpp

@@ -26,4 +26,7 @@ namespace llarp
   nlohmann::json
   to_json(const Duration_t& t);
 
+  std::ostream&
+  operator<<(std::ostream& out, const TimePoint_t& t);
+
 }  // namespace llarp

llarp/util/types.hpp

@@ -14,6 +14,9 @@ namespace llarp
   /// convert to milliseconds
   uint64_t
   ToMS(Duration_t duration);
+
+  using DateClock_t = std::chrono::system_clock;
+  using TimePoint_t = DateClock_t::time_point;
 }  // namespace llarp
 
 using llarp_time_t = llarp::Duration_t;