Added enable flag for periodic task

core/include/userver/utils/periodic_task.hpp

@@ -124,6 +124,9 @@ class PeriodicTask final {
         /// PeriodicTask::Start() calls engine::current_task::GetTaskProcessor()
         /// to get the TaskProcessor.
         engine::TaskProcessor* task_processor{nullptr};
+
+        /// @brief enabled allows to enable/disable timer during run
+        bool enabled{true};
     };
 
     /// Signature of the task to be executed each period.

core/src/utils/periodic_task.cpp

@@ -22,8 +22,8 @@ namespace {
 
 auto TieSettings(const PeriodicTask::Settings& settings) {
     // Can't use Boost.Pfr, because Settings has custom constructors.
-    const auto& [f1, f2, f3, f4, f5, f6] = settings;
-    return std::tie(f1, f2, f3, f4, f5, f6);
+    const auto& [f1, f2, f3, f4, f5, f6, f7] = settings;
+    return std::tie(f1, f2, f3, f4, f5, f6, f7);
 }
 
 }  // namespace
@@ -98,6 +98,7 @@ void PeriodicTask::Stop() noexcept {
 }
 
 void PeriodicTask::SetSettings(Settings settings) {
+
     bool should_notify_task{};
     {
         auto writer = settings_.StartWrite();
@@ -106,7 +107,7 @@ void PeriodicTask::SetSettings(Settings settings) {
             return;
         }
         settings.flags = writer->flags;
-        should_notify_task = settings.period != writer->period || settings.exception_period != writer->exception_period;
+        should_notify_task = settings.period != writer->period || settings.exception_period != writer->exception_period || settings.enabled != writer->enabled;
         *writer = std::move(settings);
         writer.Commit();
     }
@@ -118,7 +119,13 @@ void PeriodicTask::SetSettings(Settings settings) {
 }
 
 void PeriodicTask::ForceStepAsync() {
+
     should_force_step_ = true;
+    auto writer = settings_.StartWrite();
+    if (!writer->enabled) {
+      writer->enabled = true;
+      writer.Commit();
+    }
     changed_event_.Send();
 }
 
@@ -145,11 +152,12 @@ void PeriodicTask::Run() {
         const auto before = std::chrono::steady_clock::now();
         bool no_exception = true;
 
-        if (!std::exchange(skip_step, false)) {
+        const auto settings = settings_.Read();
+        bool taskEnabled = settings->enabled;
+        if (!std::exchange(skip_step, false) && taskEnabled) {
             no_exception = Step();
         }
 
-        const auto settings = settings_.Read();
         auto period = settings->period;
         const auto exception_period = settings->exception_period.value_or(period);
 
@@ -162,12 +170,17 @@ void PeriodicTask::Run() {
             start = std::chrono::steady_clock::now();
         }
 
-        while (changed_event_.WaitForEventUntil(start + MutatePeriod(period))) {
+        while ((!taskEnabled && changed_event_.WaitForEvent()) || (taskEnabled && changed_event_.WaitForEventUntil(start + MutatePeriod(period)))) {
             if (should_force_step_.exchange(false)) {
-                break;
+              break;
             }
             // The config variable value has been changed, reload
             const auto settings = settings_.Read();
+            taskEnabled = settings->enabled;
+            if(!taskEnabled) {
+              break;
+            }
+
             period = settings->period;
             const auto exception_period = settings->exception_period.value_or(period);
             if (!no_exception) period = exception_period;

core/src/utils/periodic_task_test.cpp

@@ -418,4 +418,39 @@ UTEST_F(PeriodicTaskLog, ErrorLog) {
     task.Stop();
 }
 
+UTEST(PeriodicTask, EnableDisable) {
+    SimpleTaskData simple;
+
+    constexpr auto period = 3ms;
+    utils::PeriodicTask::Settings settings(period);
+
+    constexpr Count n = 10;
+
+    const auto start = std::chrono::steady_clock::now();
+    utils::PeriodicTask task("task", period, simple.GetTaskFunction());
+    EXPECT_TRUE(simple.WaitFor(period * n * kSlowRatio, [&simple]() { return simple.GetCount() > 5; }));
+    auto countBeforeStop = simple.GetCount();
+    settings.enabled = false;
+    task.SetSettings(settings);
+    EXPECT_FALSE(simple.WaitFor(period * n * kSlowRatio, [&simple]() { return simple.GetCount() > 10; }));
+    EXPECT_TRUE(countBeforeStop == simple.GetCount());
+    EXPECT_TRUE(task.IsRunning());
+    settings.enabled = true;
+    task.SetSettings(settings);
+    EXPECT_TRUE(simple.WaitFor(period * n * kSlowRatio, [&simple,countBeforeStop]() { return simple.GetCount() > 10; }));
+    EXPECT_TRUE(task.IsRunning());
+    auto countBeforeStop2 = simple.GetCount();
+    settings.enabled = false;
+    task.SetSettings(settings);
+    EXPECT_FALSE(simple.WaitFor(period * n * kSlowRatio, [&simple]() { return simple.GetCount() > 20; }));
+    EXPECT_TRUE(countBeforeStop2 == simple.GetCount());
+    EXPECT_TRUE(task.IsRunning());
+
+    task.ForceStepAsync();
+    EXPECT_TRUE(simple.WaitFor(period * n * kSlowRatio, [&simple]() { return simple.GetCount() > 30; }));
+
+    task.Stop();
+    EXPECT_TRUE(!task.IsRunning());
+}
+
 USERVER_NAMESPACE_END