From ccecd5996a7b5c5b3281860186b30048a2ee4763 Mon Sep 17 00:00:00 2001
From: Smilencer <527646889@qq.com>
Date: Wed, 30 Sep 2020 04:21:23 -0500
Subject: [PATCH] feat(hotkey): Add an interface of on_detect_hotkey (#634)

---
 include/dsn/dist/replication/replication_app_base.h | 7 +++++++
 src/replica/replica.cpp                             | 6 ++++++
 src/replica/replica.h                               | 2 ++
 src/replica/replica_stub.cpp                        | 2 +-
 4 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/include/dsn/dist/replication/replication_app_base.h b/include/dsn/dist/replication/replication_app_base.h
index dbe35f24c9..b22cf98b11 100644
--- a/include/dsn/dist/replication/replication_app_base.h
+++ b/include/dsn/dist/replication/replication_app_base.h
@@ -242,6 +242,13 @@ class replication_app_base : public replica_base
 
     virtual ingestion_status::type get_ingestion_status() { return ingestion_status::IS_INVALID; }
 
+    virtual void on_detect_hotkey(const detect_hotkey_request &req,
+                                  /*out*/ detect_hotkey_response &resp)
+    {
+        resp.err = dsn::ERR_OBJECT_NOT_FOUND;
+        resp.__set_err_hint("on_detect_hotkey implementation not found");
+    }
+
 public:
     //
     // utility functions to be used by app
diff --git a/src/replica/replica.cpp b/src/replica/replica.cpp
index e0de73e2e5..17f5a54773 100644
--- a/src/replica/replica.cpp
+++ b/src/replica/replica.cpp
@@ -459,5 +459,11 @@ void replica::init_table_level_latency_counters()
         }
     }
 }
+
+void replica::on_detect_hotkey(const detect_hotkey_request &req, detect_hotkey_response &resp)
+{
+    _app->on_detect_hotkey(req, resp);
+}
+
 } // namespace replication
 } // namespace dsn
diff --git a/src/replica/replica.h b/src/replica/replica.h
index 83dd756d19..a031aad721 100644
--- a/src/replica/replica.h
+++ b/src/replica/replica.h
@@ -383,6 +383,8 @@ class replica : public serverlet<replica>, public ref_counter, public replica_ba
 
     void init_table_level_latency_counters();
 
+    void on_detect_hotkey(const detect_hotkey_request &req, /*out*/ detect_hotkey_response &resp);
+
 private:
     friend class ::dsn::replication::test::test_checker;
     friend class ::dsn::replication::mutation_queue;
diff --git a/src/replica/replica_stub.cpp b/src/replica/replica_stub.cpp
index 4d98671013..fe126db68c 100644
--- a/src/replica/replica_stub.cpp
+++ b/src/replica/replica_stub.cpp
@@ -2784,7 +2784,7 @@ void replica_stub::on_detect_hotkey(detect_hotkey_rpc rpc)
 
     replica_ptr rep = get_replica(request.pid);
     if (rep != nullptr) {
-        response.err = ERR_OK;
+        rep->on_detect_hotkey(request, response);
     } else {
         response.err = ERR_OBJECT_NOT_FOUND;
         response.err_hint = fmt::format("not find the replica {} \n", request.pid);