Remove GroupKeyCodec.

It's not needed; all that code already exists in Structs::GroupKey.

The XML change is to fix a compile issue due to the type being wrong,
but pretty much all the XML is wrong there.
project-chip#13176 tracks
addressing that.

src/app/clusters/group-key-mgmt-server/group-key-mgmt-server.cpp

@@ -40,59 +40,6 @@ using namespace chip::app::Clusters;
 
 namespace {
 
-struct GroupKeyCodec
-{
-    static const TLV::Tag kTagFabric = TLV::ContextTag(to_underlying(GroupKeyManagement::Structs::GroupKey::Fields::kFabricIndex));
-    static const TLV::Tag kTagGroup  = TLV::ContextTag(to_underlying(GroupKeyManagement::Structs::GroupKey::Fields::kGroupId));
-    static const TLV::Tag kTagKeyset =
-        TLV::ContextTag(to_underlying(GroupKeyManagement::Structs::GroupKey::Fields::kGroupKeySetID));
-
-    chip::FabricIndex mFabric = 0;
-    GroupDataProvider::GroupKey mMapping;
-
-    GroupKeyCodec() = default;
-    GroupKeyCodec(chip::FabricIndex fabric_index, const GroupDataProvider::GroupKey & mapping) :
-        mFabric(fabric_index), mMapping(mapping)
-    {}
-
-    CHIP_ERROR Encode(TLV::TLVWriter & writer, TLV::Tag tag) const
-    {
-        TLV::TLVType outer;
-        ReturnErrorOnFailure(writer.StartContainer(tag, TLV::kTLVType_Structure, outer));
-
-        // FabricIndex
-        ReturnErrorOnFailure(DataModel::Encode(writer, kTagFabric, mFabric));
-        // GroupId
-        ReturnErrorOnFailure(DataModel::Encode(writer, kTagGroup, mMapping.group_id));
-        // GroupKeySetID
-        ReturnErrorOnFailure(DataModel::Encode(writer, kTagKeyset, mMapping.keyset_id));
-
-        ReturnErrorOnFailure(writer.EndContainer(outer));
-        return CHIP_NO_ERROR;
-    }
-
-    CHIP_ERROR Decode(TLV::TLVReader & reader)
-    {
-        TLV::TLVType outer;
-
-        VerifyOrReturnError(TLV::kTLVType_Structure == reader.GetType(), CHIP_ERROR_WRONG_TLV_TYPE);
-        ReturnErrorOnFailure(reader.EnterContainer(outer));
-
-        // FabricIndex
-        ReturnErrorOnFailure(reader.Next(kTagFabric));
-        ReturnErrorOnFailure(reader.Get(mFabric));
-        // GroupId
-        ReturnErrorOnFailure(reader.Next(kTagGroup));
-        ReturnErrorOnFailure(reader.Get(mMapping.group_id));
-        // GroupKeySetID
-        ReturnErrorOnFailure(reader.Next(kTagKeyset));
-        ReturnErrorOnFailure(reader.Get(mMapping.keyset_id));
-
-        ReturnErrorOnFailure(reader.ExitContainer(outer));
-        return CHIP_NO_ERROR;
-    }
-};
-
 struct GroupTableCodec
 {
     static const TLV::Tag kTagFabric = TLV::ContextTag(to_underlying(GroupKeyManagement::Structs::GroupInfo::Fields::kFabricIndex));
@@ -203,7 +150,10 @@ class GroupKeyManagementAttributeAccess : public AttributeAccessInterface
             GroupDataProvider::GroupKey mapping;
             while (iter->Next(mapping))
             {
-                encoder.Encode(GroupKeyCodec(fabric_index, mapping));
+                GroupKeyManagement::Structs::GroupKey::Type key = { .fabricIndex   = fabric_index,
+                                                                    .groupId       = mapping.group_id,
+                                                                    .groupKeySetID = mapping.keyset_id };
+                encoder.Encode(key);
             }
             iter->Release();
             return CHIP_NO_ERROR;
@@ -215,7 +165,7 @@ class GroupKeyManagementAttributeAccess : public AttributeAccessInterface
     {
         auto fabric_index = aDecoder.AccessingFabricIndex();
         auto provider     = GetGroupDataProvider();
-        DataModel::DecodableList<GroupKeyCodec> list;
+        GroupKeyManagement::Attributes::GroupKeyMap::TypeInfo::DecodableType list;
         size_t new_count;
 
         VerifyOrReturnError(nullptr != provider, CHIP_ERROR_INTERNAL);
@@ -230,9 +180,10 @@ class GroupKeyManagementAttributeAccess : public AttributeAccessInterface
         size_t i  = 0;
         while (iter.Next())
         {
-            const GroupKeyCodec & value = iter.GetValue();
-            VerifyOrReturnError(fabric_index == value.mFabric, CHIP_ERROR_INVALID_FABRIC_ID);
-            ReturnErrorOnFailure(provider->SetGroupKeyAt(value.mFabric, i++, value.mMapping));
+            const auto & value = iter.GetValue();
+            VerifyOrReturnError(fabric_index == value.fabricIndex, CHIP_ERROR_INVALID_FABRIC_ID);
+            ReturnErrorOnFailure(
+                provider->SetGroupKeyAt(value.fabricIndex, i++, GroupDataProvider::GroupKey(value.groupId, value.groupKeySetID)));
         }
         ReturnErrorOnFailure(iter.GetStatus());
         return CHIP_NO_ERROR;

src/app/zap-templates/zcl/data-model/chip/group-key-mgmt-cluster.xml

@@ -19,7 +19,7 @@ limitations under the License.
 
   <struct name="GroupKey">
     <cluster code="0x003F"/>
-    <item fieldId="0" name="fabricIndex" type="INT16U"/>
+    <item fieldId="0" name="fabricIndex" type="fabric_idx"/>
     <item fieldId="1" name="groupId" type="INT16U"/>
     <item fieldId="2" name="groupKeySetID" type="INT16U"/>
   </struct>
@@ -96,4 +96,4 @@ limitations under the License.
     </command>
 
   </cluster>
-</configurator>
+</configurator>