Move ::WriteAttribute validation inside Interaction Model Write Handling

src/app/WriteHandler.cpp

@@ -788,9 +788,13 @@ DataModel::ActionReturnStatus WriteHandler::CheckWriteAllowed(const Access::Subj
     {
         // NOTE: explicit cast/check only for attribute path and nothing else.
         //
-        //       In particular `request.path` is a DATA path (contains a list index)
-        //       and we do not want mLastSuccessfullyWrittenPath to be auto-cast to a
+        //       Specifically we DO NOT use `operator==` because `aPath` is a
+        //       DATA path (contains a list index) and we do not want
+        //       mLastSuccessfullyWrittenPath to be auto-cast to a
         //       data path with a empty list and fail the compare.
+        //
+        //       This inline endpoint/cluster/attribute compare results in
+        //       smaller code as well.
         if ((aPath.mEndpointId == mLastSuccessfullyWrittenPath->mEndpointId) &&
             (aPath.mClusterId == mLastSuccessfullyWrittenPath->mClusterId) &&
             (aPath.mAttributeId == mLastSuccessfullyWrittenPath->mAttributeId))
@@ -830,6 +834,9 @@ CHIP_ERROR WriteHandler::WriteClusterData(const Access::SubjectDescriptor & aSub
     // the write is done via the DataModel interface
     VerifyOrReturnError(mDataModelProvider != nullptr, CHIP_ERROR_INCORRECT_STATE);
 
+    ChipLogDetail(DataManagement, "Writing attribute: Cluster=" ChipLogFormatMEI " Endpoint=0x%x AttributeId=" ChipLogFormatMEI,
+                  ChipLogValueMEI(aPath.mClusterId), aPath.mEndpointId, ChipLogValueMEI(aPath.mAttributeId));
+
     DataModel::ActionReturnStatus status = CheckWriteAllowed(aSubject, aPath);
     if (status.IsSuccess())
     {

src/app/data-model-provider/MetadataLookup.cpp

@@ -73,7 +73,7 @@ Protocols::InteractionModel::Status ValidateClusterPath(ProviderMetadataTree * p
         return successStatus;
     }
 
-    // if we get here, the path is invalid.
+    // If we get here, the cluster identified by the path does not exist.
     auto endpoints = provider->EndpointsIgnoreError();
     for (auto & endpointEntry : endpoints)
     {

src/app/data-model-provider/MetadataLookup.h

@@ -66,10 +66,10 @@ class AttributeFinder
     ReadOnlyBuffer<AttributeEntry> mAttributes;
 };
 
-/// Validates that `path` exists within the given provider
+/// Validates that the cluster identified by `path` exists within the given provider.
 ///
-/// If `endpointID` is not valid, will return Status::UnsupportedEndpoint
-/// If `clusterId` is not valid, will return Status::UnsupportedCluster
+/// If the endpoint identified by the path does not exist, will return Status::UnsupportedEndpoint.
+/// If the endpoint exists but does not have the cluster identified by the path, will return Status::UnsupportedCluster.
 ///
 /// otherwise, it will return successStatus.
 Protocols::InteractionModel::Status ValidateClusterPath(ProviderMetadataTree * provider, const ConcreteClusterPath & path,

src/app/data-model-provider/Provider.h

@@ -72,7 +72,7 @@ class Provider : public ProviderMetadataTree
     ///
     /// When this is invoked, caller is expected to have already done some validations:
     ///    - cluster `data version` has been checked for the incoming request if applicable
-    ///    - validation of ACL/timed interaction flags/writability
+    ///    - validation of ACL/timed interaction flags/writability, if those checks are desired.
     virtual ActionReturnStatus WriteAttribute(const WriteAttributeRequest & request, AttributeValueDecoder & decoder) = 0;
 
     /// `handler` is used to send back the reply.

src/data-model-providers/codegen/CodegenDataModelProvider_Write.cpp

@@ -91,9 +91,6 @@ std::optional<CHIP_ERROR> TryWriteViaAccessInterface(const ConcreteDataAttribute
 DataModel::ActionReturnStatus CodegenDataModelProvider::WriteAttribute(const DataModel::WriteAttributeRequest & request,
                                                                        AttributeValueDecoder & decoder)
 {
-    ChipLogDetail(DataManagement, "Writing attribute: Cluster=" ChipLogFormatMEI " Endpoint=0x%x AttributeId=" ChipLogFormatMEI,
-                  ChipLogValueMEI(request.path.mClusterId), request.path.mEndpointId, ChipLogValueMEI(request.path.mAttributeId));
-
     auto metadata = Ember::FindAttributeMetadata(request.path);
 
     // Explicit failure in finding a suitable metadata