Allow Thermostat delegate to provide timeout for atomic requests

Author: hasty

examples/thermostat/linux/include/thermostat-delegate-impl.h

@@ -44,6 +44,9 @@ class ThermostatDelegate : public Delegate
 public:
     static inline ThermostatDelegate & GetInstance() { return sInstance; }
 
+    System::Clock::Milliseconds16 GetAtomicWriteTimeout(DataModel::DecodableList<chip::AttributeId> attributeRequests,
+                                                        System::Clock::Milliseconds16 timeoutRequest) override;
+
     CHIP_ERROR GetPresetTypeAtIndex(size_t index, Structs::PresetTypeStruct::Type & presetType) override;
 
     uint8_t GetNumberOfPresets() override;

examples/thermostat/linux/thermostat-delegate-impl.cpp

@@ -148,6 +148,44 @@ CHIP_ERROR ThermostatDelegate::SetActivePresetHandle(const DataModel::Nullable<B
     return CHIP_NO_ERROR;
 }
 
+System::Clock::Milliseconds16
+ThermostatDelegate::GetAtomicWriteTimeout(DataModel::DecodableList<chip::AttributeId> attributeRequests,
+                                          System::Clock::Milliseconds16 timeoutRequest)
+{
+    auto attributeIdsIter = attributeRequests.begin();
+    bool requestedPresets = false, requestedSchedules = false;
+    while (attributeIdsIter.Next())
+    {
+        auto & attributeId = attributeIdsIter.GetValue();
+
+        switch (attributeId)
+        {
+        case Attributes::Presets::Id:
+            requestedPresets = true;
+            break;
+        case Attributes::Schedules::Id:
+            requestedSchedules = true;
+            break;
+        default:
+            return System::Clock::Milliseconds16(0);
+        }
+    }
+    if (attributeIdsIter.GetStatus() != CHIP_NO_ERROR)
+    {
+        return System::Clock::Milliseconds16(0);
+    }
+    auto timeout = System::Clock::Milliseconds16(0);
+    if (requestedPresets)
+    {
+        timeout += std::chrono::milliseconds(1000);
+    }
+    if (requestedSchedules)
+    {
+        timeout += std::chrono::milliseconds(3000);
+    }
+    return std::min(timeoutRequest, timeout);
+}
+
 void ThermostatDelegate::InitializePendingPresets()
 {
     mNextFreeIndexInPendingPresetsList = 0;

src/app/clusters/thermostat-server/thermostat-delegate.h

@@ -38,6 +38,16 @@ class Delegate
 
     virtual ~Delegate() = default;
 
+    /**
+     * @brief Get the maximum timeout for atomically writing to a set of attributes
+     *
+     * @param[in] attributeRequests The list of attributes to write to.
+     * @param[out] timeoutRequest The timeout proposed by the client.
+     * @return The maximum allowed timeout; zero if the request is invalid.
+     */
+    virtual System::Clock::Milliseconds16 GetAtomicWriteTimeout(DataModel::DecodableList<chip::AttributeId> attributeRequests,
+                                                                System::Clock::Milliseconds16 timeoutRequest) = 0;
+
     /**
      * @brief Get the preset type at a given index in the PresetTypes attribute
      *

src/app/clusters/thermostat-server/thermostat-server.cpp

@@ -1402,8 +1402,6 @@ void handleAtomicBegin(CommandHandler * commandObj, const ConcreteCommandPath &
         return;
     }
 
-    auto timeout = commandData.timeout.Value();
-
     if (!validAtomicAttributes(commandData, false))
     {
         commandObj->AddStatus(commandPath, imcode::InvalidCommand);
@@ -1420,12 +1418,17 @@ void handleAtomicBegin(CommandHandler * commandObj, const ConcreteCommandPath &
     // needs to keep track of a pending preset list now.
     delegate->InitializePendingPresets();
 
-    uint16_t maxTimeout = 5000;
-    timeout             = std::min(timeout, maxTimeout);
+    System::Clock::Milliseconds16 timeout =
+        delegate->GetAtomicWriteTimeout(commandData.attributeRequests, System::Clock::Milliseconds16(commandData.timeout.Value()));
 
-    ScheduleTimer(endpoint, System::Clock::Milliseconds16(timeout));
+    if (timeout == System::Clock::Milliseconds16(0))
+    {
+        commandObj->AddStatus(commandPath, imcode::InvalidCommand);
+        return;
+    }
+    ScheduleTimer(endpoint, timeout);
     gThermostatAttrAccess.SetAtomicWrite(endpoint, GetSourceScopedNodeId(commandObj), true);
-    sendAtomicResponse(commandObj, commandPath, imcode::Success, imcode::Success, imcode::Success, MakeOptional(timeout));
+    sendAtomicResponse(commandObj, commandPath, imcode::Success, imcode::Success, imcode::Success, MakeOptional(timeout.count()));
 }
 
 imcode commitPresets(Delegate * delegate, EndpointId endpoint)