ValidatingWriter.hh

#ifndef avro_ValidatingWriter_hh__
#define avro_ValidatingWriter_hh__

#include <boost/noncopyable.hpp>

#include "Writer.hh"
#include "Validator.hh"
#include "AvroTraits.hh"

namespace avro {

class ValidSchema;
class OutputStreamer;


class ValidatingWriter : private boost::noncopyable
{

  public:

    ValidatingWriter(const ValidSchema &schema, OutputStreamer &out);

    template<typename T>
    void writeValue(T val) {
        checkSafeToPut(type_to_avro<T>::type);
        writer_.writeValue(val);
        validator_.advance();
    }

    void writeValue(const std::string &val) {
        checkSafeToPut(type_to_avro<std::string>::type);
        writer_.writeValue(val);
        validator_.advance();
    }

    void writeBytes(const void *val, size_t size);

    template <size_t N>
    void writeFixed(const uint8_t (&val)[N]) {
        checkSafeToPut(AVRO_FIXED);
        checkSizeExpected(N);
        writer_.writeFixed(val);
        validator_.advance();
    }

    template <size_t N>
    void writeFixed(const boost::array<uint8_t, N> &val) {
        checkSafeToPut(AVRO_FIXED);
        checkSizeExpected(val.size());
        writer_.writeFixed(val);
        validator_.advance();
    }

    void writeRecord();

    void writeArrayBlock(int64_t size);
    void writeArrayEnd();

    void writeMapBlock(int64_t size);
    void writeMapEnd();

    void writeUnion(int64_t choice);

    void writeEnum(int64_t choice);

  private:

    void writeCount(int64_t count);

    void checkSafeToPut(Type type) const {
        if(! validator_.typeIsExpected(type)) {
            throw Exception("Type does not match schema");
        }
    }

    void checkSizeExpected(int size) const {
        if(validator_.nextSizeExpected() != size) {
            throw Exception("Wrong size of for fixed");
        }
    }

    Validator validator_;
    Writer writer_;

};

} // namespace avro

#endif