Optimize the implementation of error handling in keep alive. (#54)

Signed-off-by: Tao He <sighingnow@gmail.com>

etcd/Response.hpp

@@ -12,6 +12,7 @@
 
 namespace etcdv3 {
   class AsyncWatchAction;
+  class AsyncLeaseKeepAliveAction;
   class V3Response;
 }
 
@@ -139,6 +140,7 @@ namespace etcd
     std::chrono::microseconds _duration; // execute duration (in microseconds), during the action created and response parsed
     friend class SyncClient;
     friend class etcdv3::AsyncWatchAction;
+    friend class etcdv3::AsyncLeaseKeepAliveAction;
     friend class Client;
   };
 }

etcd/v3/AsyncLeaseAction.hpp

@@ -7,6 +7,7 @@
 #include "proto/rpc.grpc.pb.h"
 #include "etcd/v3/Action.hpp"
 #include "etcd/v3/AsyncLeaseResponse.hpp"
+#include "etcd/Response.hpp"
 
 using grpc::ClientAsyncResponseReader;
 using grpc::ClientAsyncReaderWriter;
@@ -45,7 +46,7 @@ namespace etcdv3
       AsyncLeaseKeepAliveAction(etcdv3::ActionParameters param);
       AsyncLeaseKeepAliveResponse ParseResponse();
 
-      AsyncLeaseKeepAliveResponse Refresh();
+      etcd::Response Refresh();
       void CancelKeepAlive();
       bool Cancelled() const;
 

src/KeepAlive.cpp

@@ -152,9 +152,18 @@ void etcd::KeepAlive::refresh()
       std::cerr << "keepalive timer error: " << error << ", " << error.message() << std::endl;
 #endif
     } else {
-      this->stubs->call->Refresh();
+      if (this->continue_next) {
-      // trigger the next round;
+        auto resp = this->stubs->call->Refresh();
-      this->refresh();
+        if (!resp.is_ok()) {
+          throw std::runtime_error("Failed to refresh lease: error code: " + std::to_string(resp.error_code()) +
+                                   ", message: " + resp.error_message());
+        }
+        if (resp.value().ttl() == -1) {
+          throw std::runtime_error("Failed to refresh lease due to expiration: the new TTL is -1.");
+        }
+        // trigger the next round;
+        this->refresh();
+      }
     }
   });
 }

src/v3/AsyncLeaseAction.cpp

@@ -82,12 +82,16 @@ etcdv3::AsyncLeaseKeepAliveResponse etcdv3::AsyncLeaseKeepAliveAction::ParseResp
   return lease_resp;
 }
 
-etcdv3::AsyncLeaseKeepAliveResponse etcdv3::AsyncLeaseKeepAliveAction::Refresh()
+etcd::Response etcdv3::AsyncLeaseKeepAliveAction::Refresh()
 {
   std::lock_guard<std::mutex> scope_lock(this->protect_is_cancelled);
 
+  auto start_timepoint = std::chrono::high_resolution_clock::now();
   if (isCancelled) {
-    return ParseResponse();
+    auto resp = ParseResponse();
+    auto duration = std::chrono::duration_cast<std::chrono::microseconds>(
+            std::chrono::high_resolution_clock::now() - start_timepoint);
+    return etcd::Response(resp, duration);
   }
 
   LeaseKeepAliveRequest leasekeepalive_request;
@@ -102,10 +106,13 @@ etcdv3::AsyncLeaseKeepAliveResponse etcdv3::AsyncLeaseKeepAliveAction::Refresh()
     stream->Read(&reply, (void*)"keepalive read");
     // wait read finish
     if (cq_.Next(&got_tag, &ok) && ok && got_tag == (void *)"keepalive read") {
-      return ParseResponse();
+      auto resp = ParseResponse();
+      auto duration = std::chrono::duration_cast<std::chrono::microseconds>(
+            std::chrono::high_resolution_clock::now() - start_timepoint);
+      return etcd::Response(resp, duration);
     }
   }
-  throw std::runtime_error("Failed to create a lease keep-alive connection");
+  return etcd::Response(grpc::StatusCode::ABORTED, "Failed to create a lease keep-alive connection");
 }
 
 void etcdv3::AsyncLeaseKeepAliveAction::CancelKeepAlive()

tst/WatcherTest.cpp

@@ -81,10 +81,10 @@ TEST_CASE("create watcher")
     etcd::Watcher watcher(etcd_uri, "/test", printResponse, true);
     std::this_thread::sleep_for(std::chrono::seconds(3));
     etcd.set("/test/key", "42");
+    std::this_thread::sleep_for(std::chrono::seconds(3));
     etcd.set("/test/key", "43");
     std::this_thread::sleep_for(std::chrono::seconds(3));
   }
-  std::this_thread::sleep_for(std::chrono::seconds(10));
   CHECK(2 == watcher_called);
   etcd.rmdir("/test", true).error_code();
 }