Add a common TBlockEvents helper class for event interception (#7767)

Co-authored-by: kungurtsev <alexey66rus@gmail.com>

ydb/core/testlib/actors/block_events.cpp

@@ -0,0 +1 @@
+#include "block_events.h"

ydb/core/testlib/actors/block_events.h

@@ -0,0 +1,82 @@
+#include "test_runtime.h"
+
+#include <deque>
+#include <functional>
+
+namespace NActors {
+
+    /**
+     * Easy blocking for events under the test actor runtime
+     *
+     * Matching events are blocked just before they are processed and stashed
+     * into a deque.
+     */
+    template<class TEvType>
+    class TBlockEvents : public std::deque<typename TEvType::TPtr> {
+    public:
+        TBlockEvents(TTestActorRuntime& runtime, std::function<bool(typename TEvType::TPtr&)> condition = {})
+            : Runtime(runtime)
+            , Condition(std::move(condition))
+            , Holder(Runtime.AddObserver<TEvType>(
+                [this](typename TEvType::TPtr& ev) {
+                    this->Process(ev);
+                }))
+        {}
+
+        /**
+         * Unblocks up to count events at the front of the deque, allowing them
+         * to be handled by the destination actor.
+         */
+        TBlockEvents& Unblock(size_t count = -1) {
+            while (!this->empty() && count > 0) {
+                auto& ev = this->front();
+                if (!Stopped) {
+                    IEventHandle* ptr = ev.Get();
+                    UnblockedOnce.insert(ptr);
+                }
+                ui32 nodeId = ev->GetRecipientRewrite().NodeId();
+                ui32 nodeIdx = nodeId - Runtime.GetFirstNodeId();
+                Runtime.Send(ev.Release(), nodeIdx, /* viaActorSystem */ true);
+                this->pop_front();
+                --count;
+            }
+            return *this;
+        }
+
+        /**
+         * Stops blocking any new events. Events currently in the deque are
+         * not unblocked, but may be unblocked at a later time if needed.
+         */
+        TBlockEvents& Stop() {
+            UnblockedOnce.clear();
+            Holder.Remove();
+            Stopped = true;
+            return *this;
+        }
+
+    private:
+        void Process(typename TEvType::TPtr& ev) {
+            IEventHandle* ptr = ev.Get();
+            auto it = UnblockedOnce.find(ptr);
+            if (it != UnblockedOnce.end()) {
+                UnblockedOnce.erase(it);
+                return;
+            }
+
+            if (Condition && !Condition(ev)) {
+                return;
+            }
+
+            this->emplace_back(std::move(ev));
+        }
+
+    private:
+        TTestActorRuntime& Runtime;
+        std::function<bool(typename TEvType::TPtr&)> Condition;
+        TTestActorRuntime::TEventObserverHolder Holder;
+        THashSet<IEventHandle*> UnblockedOnce;
+        bool Stopped = false;
+    };
+
+
+} // namespace NActors

ydb/core/testlib/actors/test_runtime_ut.cpp

@@ -1,4 +1,5 @@
 #include <ydb/core/testlib/actors/test_runtime.h>
+#include <ydb/core/testlib/actors/block_events.h>
 #include <ydb/core/base/appdata.h>
 #include <ydb/library/actors/core/event_local.h>
 #include <ydb/library/actors/core/events.h>
@@ -717,6 +718,114 @@ Y_UNIT_TEST_SUITE(TActorTest) {
         runtime.WaitFor("value = 42", [&]{ return value == 42; });
         UNIT_ASSERT_VALUES_EQUAL(value, 42);
     }
-};
+
+    Y_UNIT_TEST(TestBlockEvents) {
+        enum EEv {
+            EvTrigger = EventSpaceBegin(TEvents::ES_PRIVATE)
+        };
+
+        struct TEvTrigger : public TEventLocal<TEvTrigger, EvTrigger> {
+            int Value;
+
+            TEvTrigger(int value)
+                : Value(value)
+            {}
+        };
+
+        class TTargetActor : public TActorBootstrapped<TTargetActor> {
+        public:
+            TTargetActor(std::vector<int>* ptr)
+                : Ptr(ptr)
+            {}
+
+            void Bootstrap() {
+                Become(&TThis::StateWork);
+            }
+
+        private:
+            STFUNC(StateWork) {
+                switch (ev->GetTypeRewrite()) {
+                    hFunc(TEvTrigger, Handle);
+                }
+            }
+
+            void Handle(TEvTrigger::TPtr& ev) {
+                Ptr->push_back(ev->Get()->Value);
+            }
+
+        private:
+            std::vector<int>* Ptr;
+        };
+
+        class TSourceActor : public TActorBootstrapped<TSourceActor> {
+        public:
+            TSourceActor(const TActorId& target)
+                : Target(target)
+            {}
+
+            void Bootstrap() {
+                Become(&TThis::StateWork);
+                Schedule(TDuration::Seconds(1), new TEvents::TEvWakeup);
+            }
+
+        private:
+            STFUNC(StateWork) {
+                switch (ev->GetTypeRewrite()) {
+                    hFunc(TEvents::TEvWakeup, Handle);
+                }
+            }
+
+            void Handle(TEvents::TEvWakeup::TPtr&) {
+                Send(Target, new TEvTrigger(++Counter));
+                Schedule(TDuration::Seconds(1), new TEvents::TEvWakeup);
+            }
+
+        private:
+            TActorId Target;
+            int Counter = 0;
+        };
+
+        TTestActorRuntime runtime(2);
+        runtime.Initialize(MakeEgg());
+
+        std::vector<int> values;
+        auto target = runtime.Register(new TTargetActor(&values), /* nodeIdx */ 1);
+        auto source = runtime.Register(new TSourceActor(target), /* nodeIdx */ 1);
+        runtime.EnableScheduleForActor(source);
+
+        TBlockEvents<TEvTrigger> block(runtime, [&](TEvTrigger::TPtr& ev){ return ev->GetRecipientRewrite() == target; });
+        runtime.WaitFor("blocked 3 events", [&]{ return block.size() >= 3; });
+        UNIT_ASSERT_VALUES_EQUAL(block.size(), 3u);
+        UNIT_ASSERT_VALUES_EQUAL(values.size(), 0u);
+
+        block.Unblock(2);
+        UNIT_ASSERT_VALUES_EQUAL(block.size(), 1u);
+        UNIT_ASSERT_VALUES_EQUAL(values.size(), 0u);
+
+        runtime.WaitFor("blocked 1 more event", [&]{ return block.size() >= 2; });
+        UNIT_ASSERT_VALUES_EQUAL(block.size(), 2u);
+        UNIT_ASSERT_VALUES_EQUAL(values.size(), 2u);
+        UNIT_ASSERT_VALUES_EQUAL(values.at(0), 1);
+        UNIT_ASSERT_VALUES_EQUAL(values.at(1), 2);
+        values.clear();
+
+        block.Stop();
+        runtime.WaitFor("processed 2 more events", [&]{ return values.size() >= 2; });
+        UNIT_ASSERT_VALUES_EQUAL(block.size(), 2u);
+        UNIT_ASSERT_VALUES_EQUAL(values.size(), 2u);
+        UNIT_ASSERT_VALUES_EQUAL(values.at(0), 5);
+        UNIT_ASSERT_VALUES_EQUAL(values.at(1), 6);
+        values.clear();
+
+        block.Unblock();
+        UNIT_ASSERT_VALUES_EQUAL(block.size(), 0u);
+        UNIT_ASSERT_VALUES_EQUAL(values.size(), 0u);
+        runtime.WaitFor("processed 3 more events", [&]{ return values.size() >= 3; });
+        UNIT_ASSERT_VALUES_EQUAL(values.size(), 3u);
+        UNIT_ASSERT_VALUES_EQUAL(values.at(0), 3);
+        UNIT_ASSERT_VALUES_EQUAL(values.at(1), 4);
+        UNIT_ASSERT_VALUES_EQUAL(values.at(2), 7);
+    }
+}
 
 }

ydb/core/testlib/actors/ya.make

@@ -1,7 +1,10 @@
 LIBRARY()
 
 SRCS(
+    block_events.cpp
+    block_events.h
     test_runtime.cpp
+    test_runtime.h
 )
 
 PEERDIR(

ydb/core/tx/datashard/datashard_ut_read_iterator.cpp

@@ -4,6 +4,7 @@
 #include "read_iterator.h"
 
 #include <ydb/core/testlib/tablet_helpers.h>
+#include <ydb/core/testlib/actors/block_events.h>
 #include <ydb/core/formats/arrow/arrow_helpers.h>
 #include <ydb/core/formats/arrow/converter.h>
 #include <ydb/core/kqp/ut/common/kqp_ut_common.h>
@@ -4627,58 +4628,6 @@ Y_UNIT_TEST_SUITE(DataShardReadIteratorConsistency) {
             "result2: " << result2);
     }
 
-    template<class TEvType>
-    class TBlockEvents : public std::deque<typename TEvType::TPtr> {
-    public:
-        TBlockEvents(TTestActorRuntime& runtime, std::function<bool(typename TEvType::TPtr&)> condition = {})
-            : Runtime(runtime)
-            , Condition(std::move(condition))
-            , Holder(Runtime.AddObserver<TEvType>(
-                [this](typename TEvType::TPtr& ev) {
-                    this->Process(ev);
-                }))
-        {}
-
-        TBlockEvents& Unblock(size_t count = -1) {
-            while (!this->empty() && count > 0) {
-                auto& ev = this->front();
-                IEventHandle* ptr = ev.Get();
-                UnblockedOnce.insert(ptr);
-                Runtime.Send(ev.Release(), 0, /* viaActorSystem */ true);
-                this->pop_front();
-                --count;
-            }
-            return *this;
-        }
-
-        void Stop() {
-            UnblockedOnce.clear();
-            Holder.Remove();
-        }
-
-    private:
-        void Process(typename TEvType::TPtr& ev) {
-            IEventHandle* ptr = ev.Get();
-            auto it = UnblockedOnce.find(ptr);
-            if (it != UnblockedOnce.end()) {
-                UnblockedOnce.erase(it);
-                return;
-            }
-
-            if (Condition && !Condition(ev)) {
-                return;
-            }
-
-            this->emplace_back(std::move(ev));
-        }
-
-    private:
-        TTestActorRuntime& Runtime;
-        std::function<bool(typename TEvType::TPtr&)> Condition;
-        TTestActorRuntime::TEventObserverHolder Holder;
-        THashSet<IEventHandle*> UnblockedOnce;
-    };
-
     Y_UNIT_TEST(Bug_7674_IteratorDuplicateRows) {
         TPortManager pm;
         TServerSettings serverSettings(pm.GetPort(2134));