Setting errors on nested model

save.js

document.save()
    .then(() => {
        ... some succcess logic handler ...
    })
    .catch((error) => {
        // mark propertiesModel as invalid - pass errors from server
        if (Ember.typeOf(error.errors) === 'array') {
            let store, modelClass, serverErrors, propertiesServerErrors

            store = this.get('store')
            modelClass = store.modelFor('document')
            serverErrors = store.serializerFor('document').extractErrors(store, modelClass, error, currentDocument.id)
            propertiesServerErrors = extractPropertiesErrors(serverErrors)

            let propertiesModelErrors = currentDocument.get('propertiesModel.errors')
            for (let attributeName in propertiesServerErrors) {
                if (propertiesServerErrors.hasOwnProperty(attributeName)) {
                    propertiesModelErrors.add(attributeName, propertiesServerErrors[attributeName])
                }
            }
        }
    })