Method UpdateMetadata

IO/CellGrid/vtkCompositeCellGridReader.cxx:215–436

};

bool vtkCompositeCellGridReader::UpdateMetadata()
{
  if (this->MetadataTime.GetMTime() >= this->GetMTime())
  {
    return false;
  }

  MetadataGuard meta(this);
  if (!this->FileName)
  { // Make sure we have a file to read.
    return false;
  }

  // All files listed in this->FileName must be absolute or are assumed
  // relative to the location of this->FileName. Get the absolute path
  // for this->FileName so we can turn relative paths into absolute ones.
  std::string err;
  auto realFileName = vtksys::SystemTools::GetRealPath(this->FileName, &err);
  if (!err.empty())
  {
    vtkErrorMacro("Could not determine location of \"" << this->FileName << "\".");
    return false;
  }
  std::vector<std::string> pathParts;
  vtksys::SystemTools::SplitPath(realFileName, pathParts);
  if (pathParts.size() < 2)
  {
    vtkErrorMacro("Could not determine parent directory of \"" << this->FileName << "\".");
    return false;
  }
  pathParts.pop_back(); // Drop the filename so we are left with the parent directory.

  // Check the file's validity.
  std::ifstream file(this->FileName);
  if (!file.good())
  {
    vtkErrorMacro("Cannot read file \"" << this->FileName << "\".");
    return false;
  }

  // Read the file into nlohmann json.
  nlohmann::json jj;
  try
  {
    jj = nlohmann::json::parse(file);
  }
  catch (...)
  {
    vtkErrorMacro("Cannot parse file \"" << this->FileName << "\".");
    return false;
  }

  vtkLogScopeF(TRACE, "UpdateMetadata");
  bool isComposite = true;
  auto jtype = jj.find("data-type");
  if (jtype == jj.end())
  {
    vtkErrorMacro("Data type is missing.");