Implement assignment lost

Author: LAN Xingcan

deps/librdkafka

@@ -392,6 +392,17 @@ KafkaConsumer.prototype.position = function(toppars) {
   return this._errorWrap(this._client.position(toppars), true);
 };
 
+/**
+ * Check whether the consumer considers the current assignment to have been
+ * lost invountarily.
+ *
+ * @throws Throws from native land if
+ * @returns {boolean} Whether the assignment have been lost or not
+ */
+KafkaConsumer.prototype.assimentLost = function() {
+  return this._client.assignmentLost();
+}
+
 /**
  * Unsubscribe from all currently subscribed topics
  *

lib/kafka-consumer.js

@@ -386,6 +386,20 @@ Baton KafkaConsumer::Position(std::vector<RdKafka::TopicPartition*> &toppars) {
   return Baton(err);
 }
 
+
+Baton KafkaConsumer::AssigmentLost() {
+  if (!IsConnected()) {
+    return Baton(RdKafka::ERR__STATE, "KafkaConsumer is not connected");
+  }
+
+  RdKafka::KafkaConsumer* consumer =
+    dynamic_cast<RdKafka::KafkaConsumer*>(m_client);
+
+  // XXX: Returning a bool by casting it to a pointer,
+  return Baton(reinterpret_cast<void*>(
+        static_cast<uintptr_t>(consumer->assignment_lost() ? true : false)));
+}
+
 Baton KafkaConsumer::Subscription() {
   if (!IsConnected()) {
     return Baton(RdKafka::ERR__STATE, "Consumer is not connected");
@@ -585,6 +599,7 @@ void KafkaConsumer::Init(v8::Local<v8::Object> exports) {
 
   Nan::SetPrototypeMethod(tpl, "committed", NodeCommitted);
   Nan::SetPrototypeMethod(tpl, "position", NodePosition);
+  Nan::SetPrototypeMethod(tpl, "assignemntLost", NodeAssignmentLost);
   Nan::SetPrototypeMethod(tpl, "assign", NodeAssign);
   Nan::SetPrototypeMethod(tpl, "incrementalAssign", NodeIncrementalAssign);
   Nan::SetPrototypeMethod(tpl, "unassign", NodeUnassign);
@@ -745,6 +760,20 @@ NAN_METHOD(KafkaConsumer::NodePosition) {
   RdKafka::TopicPartition::destroy(toppars);
 }
 
+NAN_METHOD(KafkaConsumer::NodeAssignmentLost) {
+
+  Nan::HandleScope scope;
+
+  KafkaConsumer* consumer = ObjectWrap::Unwrap<KafkaConsumer>(info.This());
+
+  Baton b = consumer->AssigmentLost();
+  if (b.err() != RdKafka::ERR_NO_ERROR) {
+    Nan::ThrowError(RdKafka::err2str(b.err()).c_str());
+  }
+  bool result = static_cast<bool>(reinterpret_cast<uintptr_t>(b.data<void*>()));
+  info.GetReturnValue().Set(Nan::New<v8::Boolean>(result));
+}
+
 NAN_METHOD(KafkaConsumer::NodeAssignments) {
   Nan::HandleScope scope;
 

src/kafka-consumer.cc

@@ -65,6 +65,7 @@ class KafkaConsumer : public Connection {
 
   Baton Committed(std::vector<RdKafka::TopicPartition*> &, int timeout_ms);
   Baton Position(std::vector<RdKafka::TopicPartition*> &);
+  Baton AssigmentLost();
 
   Baton RefreshAssignments();
 
@@ -101,7 +102,7 @@ class KafkaConsumer : public Connection {
   bool m_is_subscribed = false;
 
   void* m_consume_loop;
-  
+
   // Node methods
   static NAN_METHOD(NodeConnect);
   static NAN_METHOD(NodeSubscribe);
@@ -117,6 +118,7 @@ class KafkaConsumer : public Connection {
   static NAN_METHOD(NodeOffsetsStore);
   static NAN_METHOD(NodeCommitted);
   static NAN_METHOD(NodePosition);
+  static NAN_METHOD(NodeAssignmentLost);
   static NAN_METHOD(NodeSubscription);
   static NAN_METHOD(NodeSeek);
   static NAN_METHOD(NodeGetWatermarkOffsets);