intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 410 insertions, 0 deletions

diff --git a/library/cpp/messagebus/oldmodule/module.h b/library/cpp/messagebus/oldmodule/module.h
new file mode 100644
index 0000000000..8d1c4a5d52
--- /dev/null
+++ b/library/cpp/messagebus/oldmodule/module.h
@@ -0,0 +1,410 @@
+#pragma once
+
+///////////////////////////////////////////////////////////////////////////
+/// \file
+/// \brief Application interface for modules
+
+/// NBus::TBusModule provides foundation for implementation of asynchnous
+/// modules that communicate with multiple external or local sessions
+/// NBus::TBusSession.
+
+/// To implement the module some virtual functions needs to be overridden:
+
+/// NBus::TBusModule::CreateExtSession() creates and registers an
+/// external session that receives incoming messages as input for module
+/// processing.
+
+/// When new incoming message arrives the new NBus::TBusJob is created.
+/// NBus::TBusJob is somewhat similar to a thread, it maintains all the state
+/// during processing of one incoming message. Default implementation of
+/// NBus::TBusJob will maintain all send and received messages during
+/// lifetime of this job. Each message, status and reply can be found
+/// within NBus::TJobState using NBus::TBusJob::GetState(). If your module
+/// needs to maintain an additional information during lifetime of the job
+/// you can derive your own class from NBus::TBusJob and override job
+/// factory method NBus::IJobFactory::CreateJobInstance() to create your instances.
+
+/// Processing of a given message starts with a call to NBus::TBusModule::Start()
+/// handler that should be overridden in the module implementation. Within
+/// the callback handler module can perform any computation and access any
+/// datastore tables that it needs. The handler can also access any module
+/// variables. However, same handler can be called from multiple threads so,
+/// it is recommended that handler only access read-only module level variables.
+
+/// Handler should use NBus::TBusJob::Send() to send messages to other client
+/// sessions and it can use NBus::TBusJob::Reply() to send reply to the main
+/// job message. When handler is done, it returns the pointer to the next handler to call
+/// when all pending messages have cleared. If handler
+/// returns pointer to itself the module will reschedule execution of this handler
+/// for a later time. This should be done in case NBus::TBusJob::Send() returns
+/// error (not MESSAGE_OK)
+
+#include "startsession.h"
+
+#include <library/cpp/messagebus/ybus.h>
+
+#include <util/generic/noncopyable.h>
+#include <util/generic/object_counter.h>
+
+namespace NBus {
+    class TBusJob;
+    class TBusModule;
+
+    namespace NPrivate {
+        struct TCallJobHandlerWorkItem;
+        struct TBusModuleImpl;
+        struct TModuleServerHandler;
+        struct TModuleClientHandler;
+        struct TJobRunner;
+    }
+
+    class TJobHandler {
+    protected:
+        typedef TJobHandler (TBusModule::*TBusHandlerPtr)(TBusJob* job, TBusMessage* mess);
+        TBusHandlerPtr MyPtr;
+
+    public:
+        template <class B>
+        TJobHandler(TJobHandler (B::*fptr)(TBusJob* job, TBusMessage* mess)) {
+            MyPtr = static_cast<TBusHandlerPtr>(fptr);
+        }
+        TJobHandler(TBusHandlerPtr fptr = nullptr) {
+            MyPtr = fptr;
+        }
+        TJobHandler(const TJobHandler&) = default;
+        TJobHandler& operator =(const TJobHandler&) = default;
+        bool operator==(TJobHandler h) const {
+            return MyPtr == h.MyPtr;
+        }
+        bool operator!=(TJobHandler h) const {
+            return MyPtr != h.MyPtr;
+        }
+        bool operator!() const {
+            return !MyPtr;
+        }
+        TJobHandler operator()(TBusModule* b, TBusJob* job, TBusMessage* mess) {
+            return (b->*MyPtr)(job, mess);
+        }
+    };
+
+    typedef void (TBusModule::*TReplyHandler)(TBusJob* job, EMessageStatus status, TBusMessage* mess, TBusMessage* reply);
+
+    ////////////////////////////////////////////////////
+    /// \brief Pending message state
+
+    struct TJobState {
+        friend class TBusJob;
+        friend class ::TCrawlerModule;
+
+        TReplyHandler Handler;
+        EMessageStatus Status;
+        TBusMessage* Message;
+        TBusMessage* Reply;
+        TBusClientSession* Session;
+        size_t NumRetries;
+        size_t MaxRetries;
+        // If != NULL then use it as destination.
+        TNetAddr Addr;
+        bool UseAddr;
+        bool OneWay;
+
+    private:
+        TJobState(TReplyHandler handler,
+                  EMessageStatus status,
+                  TBusMessage* mess, TBusClientSession* session, TBusMessage* reply, size_t maxRetries = 0,
+                  const TNetAddr* addr = nullptr, bool oneWay = false)
+            : Handler(handler)
+            , Status(status)
+            , Message(mess)
+            , Reply(reply)
+            , Session(session)
+            , NumRetries(0)
+            , MaxRetries(maxRetries)
+            , OneWay(oneWay)
+        {
+            if (!!addr) {
+                Addr = *addr;
+            }
+            UseAddr = !!addr;
+        }
+
+    public:
+        TString GetStatus(unsigned flags);
+    };
+
+    using TJobStateVec = TVector<TJobState>;
+
+    /////////////////////////////////////////////////////////
+    /// \brief Execution item = thread
+
+    /// Maintains internal state of document in computation
+    class TBusJob {
+        TObjectCounter<TBusJob> ObjectCounter;
+
+    private:
+        void CheckThreadCurrentJob();
+
+    public:
+        /// given a module and starter message
+        TBusJob(TBusModule* module, TBusMessage* message);
+
+        /// destructor will free all the message that were send and received
+        virtual ~TBusJob();
+
+        TBusMessage* GetMessage() const {
+            return Message;
+        }
+
+        TNetAddr GetPeerAddrNetAddr() const;
+
+        /// send message to any other session or application
+        /// If addr is set then use it as destination.
+        void Send(TBusMessageAutoPtr mess, TBusClientSession* session, TReplyHandler rhandler, size_t maxRetries, const TNetAddr& addr);
+        void Send(TBusMessageAutoPtr mess, TBusClientSession* session, TReplyHandler rhandler = nullptr, size_t maxRetries = 0);
+
+        void SendOneWayTo(TBusMessageAutoPtr req, TBusClientSession* session, const TNetAddr& addr);
+        void SendOneWayWithLocator(TBusMessageAutoPtr req, TBusClientSession* session);
+
+        /// send reply to the starter message
+        virtual void SendReply(TBusMessageAutoPtr reply);
+
+        /// set the flag to terminate job at the earliest convenience
+        void Cancel(EMessageStatus status);
+
+        /// helper to put item on finished list of states
+        /// It should not be a part of public API,
+        /// so prohibit it for all except current users.
+    private:
+        friend class ::TCrawlerModule;
+        void PutState(const TJobState& state) {
+            Finished.push_back(state);
+        }
+
+    public:
+        /// retrieve all pending messages
+        void GetPending(TJobStateVec* stateVec) {
+            Y_ASSERT(stateVec);
+            *stateVec = Pending;
+        }
+
+        /// helper function to find state of previously sent messages
+        template <class MessageType>
+        TJobState* GetState(int* startFrom = nullptr) {
+            for (int i = startFrom ? *startFrom : 0; i < int(Finished.size()); i++) {
+                TJobState* call = &Finished[i];
+                if (call->Reply != nullptr && dynamic_cast<MessageType*>(call->Reply)) {
+                    if (startFrom) {
+                        *startFrom = i;
+                    }
+                    return call;
+                }
+                if (call->Message != nullptr && dynamic_cast<MessageType*>(call->Message)) {
+                    if (startFrom) {
+                        *startFrom = i;
+                    }
+                    return call;
+                }
+            }
+            return nullptr;
+        }
+
+        /// helper function to find response for previously sent messages
+        template <class MessageType>
+        MessageType* Get(int* startFrom = nullptr) {
+            for (int i = startFrom ? *startFrom : 0; i < int(Finished.size()); i++) {
+                TJobState& call = Finished[i];
+                if (call.Reply != nullptr && dynamic_cast<MessageType*>(call.Reply)) {
+                    if (startFrom) {
+                        *startFrom = i;
+                    }
+                    return static_cast<MessageType*>(call.Reply);
+                }
+                if (call.Message != nullptr && dynamic_cast<MessageType*>(call.Message)) {
+                    if (startFrom) {
+                        *startFrom = i;
+                    }
+                    return static_cast<MessageType*>(call.Message);
+                }
+            }
+            return nullptr;
+        }
+
+        /// helper function to find status for previously sent message
+        template <class MessageType>
+        EMessageStatus GetStatus(int* startFrom = nullptr) {
+            for (int i = startFrom ? *startFrom : 0; i < int(Finished.size()); i++) {
+                TJobState& call = Finished[i];
+                if (call.Message != nullptr && dynamic_cast<MessageType*>(call.Message)) {
+                    if (startFrom) {
+                        *startFrom = i;
+                    }
+                    return call.Status;
+                }
+            }
+            return MESSAGE_UNKNOWN;
+        }
+
+        /// helper function to clear state of previosly sent messages
+        template <class MessageType>
+        void Clear() {
+            for (size_t i = 0; i < Finished.size();) {
+                // `Finished.size() - i` decreases with each iteration
+                //  we either increment i, or remove element from Finished.
+                TJobState& call = Finished[i];
+                if (call.Message != nullptr && dynamic_cast<MessageType*>(call.Message)) {
+                    ClearState(call);
+                } else {
+                    ++i;
+                }
+            }
+        }
+
+        /// helper function to clear state in order to try again
+        void ClearState(TJobState& state);
+
+        /// clears all message states
+        void ClearAllMessageStates();
+
+        /// returns true if job is done
+        bool IsDone();
+
+        /// return human reabable status of this job
+        virtual TString GetStatus(unsigned flags);
+
+        /// set sleep time for job
+        void Sleep(int milliSeconds);
+
+        void CallJobHandlerOnly();
+
+    private:
+        bool CallJobHandler();
+        void DoCallReplyHandler(TJobState&);
+        /// send out all Pending jobs, failed sends will be migrated to Finished
+        bool SendPending();
+        bool AnyPendingToSend();
+
+    public:
+        /// helper to call from OnReply() and OnError()
+        int CallReplyHandler(EMessageStatus status, TBusMessage* mess, TBusMessage* reply);
+
+    public:
+        TJobHandler Handler;   ///< job handler to be executed within next CallJobHandler()
+        EMessageStatus Status; ///< set != MESSAGE_OK if job should terminate asap
+    private:
+        NPrivate::TJobRunner* Runner;
+        TBusMessage* Message;
+        THolder<TBusMessage> MessageHolder;
+        TOnMessageContext OnMessageContext; // starter
+    public:
+        bool ReplySent;
+
+    private:
+        friend class TBusModule;
+        friend struct NPrivate::TBusModuleImpl;
+        friend struct NPrivate::TCallJobHandlerWorkItem;
+        friend struct NPrivate::TModuleServerHandler;
+        friend struct NPrivate::TModuleClientHandler;
+        friend struct NPrivate::TJobRunner;
+
+        TJobStateVec Pending;  ///< messages currently outstanding via Send()
+        TJobStateVec Finished; ///< messages that were replied to
+        TBusModule* Module;
+        NPrivate::TBusModuleImpl* ModuleImpl; ///< module which created the job
+        TBusInstant SleepUntil;               ///< time to wakeup, 0 if no sleep
+    };
+
+    ////////////////////////////////////////////////////////////////////
+    /// \brief Classes to implement basic module functionality
+
+    class IJobFactory {
+    protected:
+        virtual ~IJobFactory() {
+        }
+
+    public:
+        /// job factory method, override to create custom jobs
+        virtual TBusJob* CreateJobInstance(TBusMessage* message) = 0;
+    };
+
+    struct TBusModuleConfig {
+        unsigned StarterMaxInFlight;
+
+        struct TSecret {
+            TDuration SchedulePeriod;
+
+            TSecret();
+        };
+        TSecret Secret;
+
+        TBusModuleConfig();
+    };
+
+    namespace NPrivate {
+        struct TBusModuleInternal: public TAtomicRefCount<TBusModuleInternal> {
+            virtual TVector<TBusClientSessionPtr> GetClientSessionsInternal() = 0;
+            virtual TVector<TBusServerSessionPtr> GetServerSessionsInternal() = 0;
+            virtual TBusMessageQueue* GetQueue() = 0;
+
+            virtual TString GetNameInternal() = 0;
+
+            virtual TString GetStatusSingleLine() = 0;
+
+            virtual ~TBusModuleInternal() {
+            }
+        };
+    }
+
+    class TBusModule: public IJobFactory, TNonCopyable {
+        friend class TBusJob;
+
+        TObjectCounter<TBusModule> ObjectCounter;
+
+        TIntrusivePtr<NPrivate::TBusModuleImpl> Impl;
+
+    public:
+        /// Each module should have a name which is used as protocol service
+        TBusModule(const char* name);
+        ~TBusModule() override;
+
+        const char* GetName() const;
+
+        void SetConfig(const TBusModuleConfig& config);
+
+        /// get status of all jobs in flight
+        TString GetStatus(unsigned flags = 0);
+
+        /// called when application is about to start
+        virtual bool StartInput();
+        /// called when application is about to exit
+        virtual bool Shutdown();
+
+        // this default implementation just creates TBusJob object
+        TBusJob* CreateJobInstance(TBusMessage* message) override;
+
+        EMessageStatus StartJob(TAutoPtr<TBusMessage> message);
+
+        /// creates private sessions, calls CreateExtSession(), should be called before StartInput()
+        bool CreatePrivateSessions(TBusMessageQueue* queue);
+
+        virtual void OnClientConnectionEvent(const TClientConnectionEvent& event);
+
+    public:
+        /// entry point into module, first function to call
+        virtual TJobHandler Start(TBusJob* job, TBusMessage* mess) = 0;
+
+    protected:
+        /// override this function to create destination session
+        virtual TBusServerSessionPtr CreateExtSession(TBusMessageQueue& queue) = 0;
+
+    public:
+        int GetModuleSessionInFlight() const;
+
+        TIntrusivePtr<NPrivate::TBusModuleInternal> GetInternal();
+
+    protected:
+        TBusServerSessionPtr CreateDefaultDestination(TBusMessageQueue& queue, TBusProtocol* proto, const TBusServerSessionConfig& config, const TString& name = TString());
+        TBusClientSessionPtr CreateDefaultSource(TBusMessageQueue& queue, TBusProtocol* proto, const TBusClientSessionConfig& config, const TString& name = TString());
+        TBusStarter* CreateDefaultStarter(TBusMessageQueue& unused, const TBusSessionConfig& config);
+    };
+
+}