Fix connection leak by request timers not cancelled in time

lib/ClientConnection.h

@@ -28,6 +28,7 @@
 #include <cstdint>
 #include <future>
 #include <optional>
+
 #ifdef USE_ASIO
 #include <asio/bind_executor.hpp>
 #include <asio/io_context.hpp>
@@ -52,8 +53,10 @@
 
 #include "AsioTimer.h"
 #include "Commands.h"
+#include "ExecutorService.h"
 #include "GetLastMessageIdResponse.h"
 #include "LookupDataResult.h"
+#include "PendingRequest.h"
 #include "SharedBuffer.h"
 #include "TimeUtils.h"
 #include "UtilAllocator.h"
@@ -66,9 +69,6 @@ class PulsarFriend;
 
 using TcpResolverPtr = std::shared_ptr<ASIO::ip::tcp::resolver>;
 
-class ExecutorService;
-using ExecutorServicePtr = std::shared_ptr<ExecutorService>;
-
 class ConnectionPool;
 class ClientConnection;
 typedef std::shared_ptr<ClientConnection> ClientConnectionPtr;
@@ -225,47 +225,6 @@ class PULSAR_PUBLIC ClientConnection : public std::enable_shared_from_this<Clien
     void handleKeepAliveTimeout(const ASIO_ERROR& ec);
 
    private:
-    struct PendingRequestData {
-        Promise<Result, ResponseData> promise;
-        DeadlineTimerPtr timer;
-        std::shared_ptr<std::atomic_bool> hasGotResponse{std::make_shared<std::atomic_bool>(false)};
-
-        void fail(Result result) {
-            cancelTimer(*timer);
-            promise.setFailed(result);
-        }
-    };
-
-    struct LookupRequestData {
-        LookupDataResultPromisePtr promise;
-        DeadlineTimerPtr timer;
-
-        void fail(Result result) {
-            cancelTimer(*timer);
-            promise->setFailed(result);
-        }
-    };
-
-    struct LastMessageIdRequestData {
-        GetLastMessageIdResponsePromisePtr promise;
-        DeadlineTimerPtr timer;
-
-        void fail(Result result) {
-            cancelTimer(*timer);
-            promise->setFailed(result);
-        }
-    };
-
-    struct GetSchemaRequest {
-        Promise<Result, SchemaInfo> promise;
-        DeadlineTimerPtr timer;
-
-        void fail(Result result) {
-            cancelTimer(*timer);
-            promise.setFailed(result);
-        }
-    };
-
     /*
      * handler for connectAsync
      * creates a ConnectionPtr which has a valid ClientConnection object
@@ -303,12 +262,6 @@ class PULSAR_PUBLIC ClientConnection : public std::enable_shared_from_this<Clien
     void newLookup(const SharedBuffer& cmd, uint64_t requestId, const char* requestType,
                    const LookupDataResultPromisePtr& promise);
 
-    void handleRequestTimeout(const ASIO_ERROR& ec, const PendingRequestData& pendingRequestData);
-
-    void handleLookupTimeout(const ASIO_ERROR&, const LookupRequestData&);
-
-    void handleGetLastMessageIdTimeout(const ASIO_ERROR&, const LastMessageIdRequestData& data);
-
     template <typename Handler>
     inline AllocHandler<Handler> customAllocReadHandler(Handler h) {
         return AllocHandler<Handler>(readHandlerAllocator_, h);
@@ -385,33 +338,49 @@ class PULSAR_PUBLIC ClientConnection : public std::enable_shared_from_this<Clien
     const std::chrono::milliseconds connectTimeout_;
     const DeadlineTimerPtr connectTimer_;
 
-    typedef std::map<long, PendingRequestData> PendingRequestsMap;
-    PendingRequestsMap pendingRequests_;
+    template <typename T>
+    using RequestMap = std::unordered_map<uint64_t, PendingRequestPtr<T>>;
 
-    typedef std::map<long, LookupRequestData> PendingLookupRequestsMap;
-    PendingLookupRequestsMap pendingLookupRequests_;
+    RequestMap<ResponseData> pendingRequests_;
+    RequestMap<LookupDataResultPtr> pendingLookupRequests_;
+    RequestMap<GetLastMessageIdResponse> pendingGetLastMessageIdRequests_;
+    RequestMap<NamespaceTopicsPtr> pendingGetNamespaceTopicsRequests_;
+    RequestMap<SchemaInfo> pendingGetSchemaRequests_;
 
-    typedef std::map<long, ProducerImplWeakPtr> ProducersMap;
+    typedef std::unordered_map<long, ProducerImplWeakPtr> ProducersMap;
     ProducersMap producers_;
 
-    typedef std::map<long, ConsumerImplWeakPtr> ConsumersMap;
+    typedef std::unordered_map<long, ConsumerImplWeakPtr> ConsumersMap;
     ConsumersMap consumers_;
 
     typedef std::map<uint64_t, Promise<Result, BrokerConsumerStatsImpl>> PendingConsumerStatsMap;
     PendingConsumerStatsMap pendingConsumerStatsMap_;
 
-    typedef std::map<long, LastMessageIdRequestData> PendingGetLastMessageIdRequestsMap;
-    PendingGetLastMessageIdRequestsMap pendingGetLastMessageIdRequests_;
-
-    typedef std::map<long, Promise<Result, NamespaceTopicsPtr>> PendingGetNamespaceTopicsMap;
-    PendingGetNamespaceTopicsMap pendingGetNamespaceTopicsRequests_;
-
-    typedef std::unordered_map<uint64_t, GetSchemaRequest> PendingGetSchemaMap;
-    PendingGetSchemaMap pendingGetSchemaRequests_;
-
     mutable std::mutex mutex_;
     typedef std::unique_lock<std::mutex> Lock;
 
+    // Note: this method must be called when holding `mutex_`
+    template <typename T, typename OnTimeout>
+    auto insertRequest(RequestMap<T>& pendingRequests, uint64_t requestId, OnTimeout onTimeout) {
+        auto request = std::make_shared<PendingRequest<T>>(
+            executor_->createTimer(operationsTimeout_),
+            [this, self{shared_from_this()}, requestId, onTimeout{std::move(onTimeout)},
+             &pendingRequests]() mutable {
+                {
+                    std::lock_guard lock{mutex_};
+                    if (auto it = pendingRequests.find(requestId); it != pendingRequests.end()) {
+                        pendingRequests.erase(it);
+                    }
+                }
+                onTimeout();
+            });
+        auto [iterator, inserted] = pendingRequests.emplace(requestId, request);
+        if (inserted) {
+            request->initialize();
+        }  // else: the request id is duplicated
+        return iterator->second;
+    }
+
     // Pending buffers to write on the socket
     std::deque<std::any> pendingWriteBuffers_;
     int pendingWriteOperations_ = 0;
@@ -435,7 +404,7 @@ class PULSAR_PUBLIC ClientConnection : public std::enable_shared_from_this<Clien
 
     void startConsumerStatsTimer(std::vector<uint64_t> consumerStatsRequests);
     uint32_t maxPendingLookupRequest_;
-    uint32_t numOfPendingLookupRequest_ = 0;
+    std::atomic_uint32_t numOfPendingLookupRequest_{0};
 
     bool isTlsAllowInsecureConnection_ = false;
 

lib/ExecutorService.h

@@ -28,12 +28,14 @@
 #include <asio/ip/tcp.hpp>
 #include <asio/post.hpp>
 #include <asio/ssl.hpp>
+#include <asio/steady_timer.hpp>
 #else
 #include <boost/asio/dispatch.hpp>
 #include <boost/asio/io_context.hpp>
 #include <boost/asio/ip/tcp.hpp>
 #include <boost/asio/post.hpp>
 #include <boost/asio/ssl.hpp>
+#include <boost/asio/steady_timer.hpp>
 #endif
 #include <chrono>
 #include <condition_variable>
@@ -68,6 +70,13 @@ class PULSAR_PUBLIC ExecutorService : public std::enable_shared_from_this<Execut
     // throws std::runtime_error if failed
     DeadlineTimerPtr createDeadlineTimer();
 
+    template <typename Duration>
+    ASIO::steady_timer createTimer(const Duration &duration) {
+        auto timer = ASIO::steady_timer(io_context_);
+        timer.expires_after(duration);
+        return timer;
+    }
+
     // Execute the task in the event loop thread asynchronously, i.e. the task will be put in the event loop
     // queue and executed later.
     template <typename T>

lib/MockServer.h

@@ -81,6 +81,26 @@ class MockServer : public std::enable_shared_from_this<MockServer> {
                              proto::CommandConsumerStatsResponse response;
                              response.set_request_id(requestId);
                              connection->handleConsumerStatsResponse(response);
+                         } else if (request == "LOOKUP") {
+                             proto::CommandLookupTopicResponse response;
+                             response.set_request_id(requestId);
+                             response.set_response(proto::CommandLookupTopicResponse_LookupType_Connect);
+                             response.set_brokerserviceurl("pulsar://localhost:6650");
+                             connection->handleLookupTopicRespose(response);
+                         } else if (request == "GET_LAST_MESSAGE_ID") {
+                             proto::CommandGetLastMessageIdResponse response;
+                             response.set_request_id(requestId);
+                             response.mutable_last_message_id();
+                             connection->handleGetLastMessageIdResponse(response);
+                         } else if (request == "GET_TOPICS_OF_NAMESPACE") {
+                             proto::CommandGetTopicsOfNamespaceResponse response;
+                             response.set_request_id(requestId);
+                             connection->handleGetTopicOfNamespaceResponse(response);
+                         } else if (request == "GET_SCHEMA") {
+                             proto::CommandGetSchemaResponse response;
+                             response.set_request_id(requestId);
+                             response.mutable_schema()->set_type(proto::Schema_Type_String);
+                             connection->handleGetSchemaResponse(response);
                          } else {
                              proto::CommandSuccess success;
                              success.set_request_id(requestId);

lib/PendingRequest.h

@@ -0,0 +1,76 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+#pragma once
+
+#include <pulsar/Result.h>
+
+#include <atomic>
+#include <functional>
+#include <memory>
+
+#include "AsioDefines.h"
+#include "AsioTimer.h"
+#include "Future.h"
+
+namespace pulsar {
+
+template <typename T>
+class PendingRequest : public std::enable_shared_from_this<PendingRequest<T>> {
+   public:
+    PendingRequest(ASIO::steady_timer timer, std::function<void()> timeoutCallback)
+        : timer_(std::move(timer)), timeoutCallback_(std::move(timeoutCallback)) {}
+
+    void initialize() {
+        timer_.async_wait([this, weakSelf{this->weak_from_this()}](const auto& error) {
+            auto self = weakSelf.lock();
+            if (!self || error || timeoutDisabled_.load(std::memory_order_acquire)) {
+                return;
+            }
+            timeoutCallback_();
+            promise_.setFailed(ResultTimeout);
+        });
+    }
+
+    void complete(const T& value) {
+        promise_.setValue(value);
+        cancelTimer(timer_);
+    }
+
+    void fail(Result result) {
+        promise_.setFailed(result);
+        cancelTimer(timer_);
+    }
+
+    void disableTimeout() { timeoutDisabled_.store(true, std::memory_order_release); }
+
+    auto getFuture() const { return promise_.getFuture(); }
+
+    ~PendingRequest() { cancelTimer(timer_); }
+
+   private:
+    ASIO::steady_timer timer_;
+    Promise<Result, T> promise_;
+    std::function<void()> timeoutCallback_;
+    std::atomic_bool timeoutDisabled_{false};
+};
+
+template <typename T>
+using PendingRequestPtr = std::shared_ptr<PendingRequest<T>>;
+
+}  // namespace pulsar