exampleObjectHandling.cpp

#include <iostream>
#include "velocypack/vpack.h"
#include "velocypack/velocypack-exception-macros.h"

using namespace arangodb::velocypack;

int main(int, char* []) {
  VELOCYPACK_GLOBAL_EXCEPTION_TRY

  // create an object with a few members
  Builder b;

  b(Value(ValueType::Object));
  b.add("foo", Value(42));
  b.add("bar", Value("some string value"));
  b.add("baz", Value(ValueType::Object));
  b.add("qux", Value(true));
  b.add("bart", Value("this is a string"));
  b.close();
  b.add("quux", Value(ValueType::Array));
  b.add(Value(1));
  b.add(Value(2));
  b.add(Value(3));
  b.close();
  b.close();

  // a Slice is a lightweight accessor for a VPack value
  Slice s(b.start());

  // get all object keys. returns a vector of strings
  for (auto const& key : Collection::keys(s)) {
    // print key
    std::cout << "Object has key '" << key << "'" << std::endl;
  }

  // get all object values. returns a Builder object with an Array inside
  Builder values = Collection::values(s);
  for (auto const& value : ArrayIterator(values.slice())) {
    std::cout << "Object value is: " << value << ", as JSON: " << value.toJson()
              << std::endl;
  }

  // recursively visit all members in the Object
  // PostOrder here means we'll be visiting compound members before
  // we're diving into their subvalues
  Collection::visitRecursive(s, Collection::PostOrder,
                             [](Slice const& key, Slice const& value) -> bool {
    if (!key.isNone()) {
      // we are visiting an Object member
      std::cout << "Visiting Object member: " << key.copyString()
                << ", value: " << value.toJson() << std::endl;
    } else {
      // we are visiting an Array member
      std::cout << "Visiting Array member: " << value.toJson() << std::endl;
    }
    // to continue visiting, return true. to abort visiting, return false
    return true;
  });
  
  VELOCYPACK_GLOBAL_EXCEPTION_CATCH
}