Function writeTreeXSD

src/xml_parsing.cpp:1473–1742

}

std::string writeTreeXSD(const BehaviorTreeFactory& factory)
{
  // There are 2 forms of representation for a node:
  // compact: <Sequence .../>  and explicit: <Control ID="Sequence" ... />
  // Only the compact form is supported because the explicit form doesn't
  // make sense with XSD since we would need to allow any attribute.
  // Prepare the data

  std::map<std::string, const TreeNodeManifest*> ordered_models;
  for(const auto& [registration_id, model] : factory.manifests())
  {
    ordered_models.insert({ registration_id, &model });
  }

  XMLDocument doc;

  // Add the XML declaration
  XMLDeclaration* declaration = doc.NewDeclaration("xml version=\"1.0\" "
                                                   "encoding=\"UTF-8\"");
  doc.InsertFirstChild(declaration);

  // Create the root element with namespace and attributes
  // To validate a BT XML file with `schema.xsd` in the same directory:
  // <root BTCPP_format="4" main_tree_to_execute="MainTree"
  //   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  //   xsi:noNamespaceSchemaLocation="schema.xsd">
  XMLElement* schema_element = doc.NewElement("xs:schema");
  schema_element->SetAttribute("xmlns:xs", "http://www.w3.org/2001/XMLSchema");
  schema_element->SetAttribute("elementFormDefault", "qualified");
  doc.InsertEndChild(schema_element);

  auto parse_and_insert = [&doc](XMLElement* parent_elem, const char* str) {
    XMLDocument tmp_doc;
    tmp_doc.Parse(str);
    if(tmp_doc.Error())
    {
      std::cerr << "Internal error parsing existing XML: " << tmp_doc.ErrorStr()
                << std::endl;
      return;
    }
    for(auto child = tmp_doc.FirstChildElement(); child != nullptr;
        child = child->NextSiblingElement())
    {
      parent_elem->InsertEndChild(child->DeepClone(&doc));
    }
  };

  // Common elements.
  XMLComment* comment = doc.NewComment("Define the common elements");
  schema_element->InsertEndChild(comment);

  // TODO: add <xs:whiteSpace value="preserve"/> for `inputPortType` and `outputPortType`.
  parse_and_insert(schema_element, R"(
    <xs:simpleType name="blackboardType">
        <xs:restriction base="xs:string">
            <xs:pattern value="\{.*\}"/>
        </xs:restriction>
    </xs:simpleType>