Bug fix: Allow empty multi instance resources

[Alex-EEE]

The client fails to register currently if a multi instance resource is created without any instances. This is allowed by the spec, in fact, it makes sense. The client may want to create a multi instance resource with no initial instances so that the server can PUT the resource instances later. (For example, our use case is just a simple place for our web team to store information specific to the IoT node in STRING format)

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Summary of changes

[teetak01]

Thanks, looks like a valid fix. Can you check the boxes in the template, and we will take a look how to patch this.

[Alex-EEE]

Ok, checked the boxes, and completed the fix with another commit.

[ristohuhtala]

Hi @Alex-EEE . @teetak01 assinged me to take this fix into our internal repository. After reviewing changes here are how those to methods will look like after this
M2MNsdlInterface::create_nsdl_resource_structure
if (res) { // if there are multiple instances supported if (multiple_instances) { const M2MResourceInstanceList &res_list = res->resource_instances(); if (!res_list.empty()) { M2MResourceInstanceList::const_iterator it; it = res_list.begin(); for ( ; it != res_list.end(); it++ ) { success = create_nsdl_resource((*it)); if (!success) { tr_error("M2MNsdlInterface::create_nsdl_resource_structure - instance creation failed"); return false; } } } } // Register the main Resource as well along with ResourceInstances success = create_nsdl_resource(res); }

M2MTLVDeserializer::deserialize_resource_instances
if(!found) { if(M2MTLVDeserializer::Post == operation) { error = M2MTLVDeserializer::NotAllowed; } else if(M2MTLVDeserializer::Put == operation) { // Create a new Resource Instance M2MResourceInstance *res_instance = resource.get_parent_object_instance().create_dynamic_resource_instance( resource.name(), "", resource.resource_instance_type(), true, til._id); if(res_instance) { res_instance->set_operation(M2MBase::PUT_ALLOWED); } } }

Edit: I am sorry, github seems to format code in comment to look really weird

[teetak01]

I'll close this now. We fixed the reported issue #71 in 4.7.1 release version.