Method extract

plugins/experimental/txn_box/plugin/src/query.cc:177–192

}

Feature
QueryValueExtractor::extract(Context &ctx, const Spec &spec)
{
  auto qs = this->query_string(ctx);
  if (qs.empty()) {
    return NIL_FEATURE;
  }
  auto &&[name, value] = ts::query_value_for(qs, spec._data.text, true); // case insensitive
  if (value.size() == 0) {
    if (value.data() == nullptr || value.data() == name.end()) {
      return NIL_FEATURE; // key not present or value not present
    }
    return FeatureView::Literal("");
  }
  return FeatureView::Direct(value);
}

// --