add a callback register interface of Part (#2485)

* add a callback register interface of Part

* add one space

* clang-format

* do another clang format

Co-authored-by: Doodle <13706157+critical27@users.noreply.github.com>

src/kvstore/Part.cpp

@@ -175,7 +175,23 @@ void Part::setBlocking(bool sign) { blocking_ = sign; }
 void Part::onLostLeadership(TermID term) { VLOG(1) << "Lost the leadership for the term " << term; }
 
 void Part::onElected(TermID term) {
- VLOG(1) << "Being elected as the leader for the term " << term;
+ VLOG(1) << "Being elected as the leader for the term: " << term;
+ if (onElectedCallBacks_.empty()) {
+ return;
+ }
+
+ CallbackOptions opt;
+ opt.spaceId = spaceId_;
+ opt.partId = partId_;
+ opt.term = term_;
+
+ for (auto& cb : onElectedCallBacks_) {
+ cb(opt);
+ }
+}
+
+void Part::registerOnElected(OnElectedCallBack cb) {
+ onElectedCallBacks_.emplace_back(std::move(cb));
 }
 
 void Part::onDiscoverNewLeader(HostAddr nLeader) {

src/kvstore/Part.h

@@ -107,11 +107,22 @@ class Part : public raftex::RaftPart {
 
  nebula::cpp2::ErrorCode toResultCode(raftex::AppendLogResult res);
 
+ public:
+ struct CallbackOptions {
+ GraphSpaceID spaceId;
+ PartitionID partId;
+ TermID term;
+ };
+
+ using OnElectedCallBack = std::function<void(const CallbackOptions& opt)>;
+ void registerOnElected(OnElectedCallBack cb);
+
  protected:
  GraphSpaceID spaceId_;
  PartitionID partId_;
  std::string walPath_;
  NewLeaderCallback newLeaderCb_ = nullptr;
+ std::vector<OnElectedCallBack> onElectedCallBacks_;
 
  private:
  KVEngine* engine_ = nullptr;