ydb/library/cpp/json/json_writer.cpp

#include "json_writer.h"

#include <util/charset/utf8.h>
#include <util/generic/algorithm.h>
#include <util/string/cast.h>
#include <util/system/yassert.h>

namespace NJson {
    TJsonWriter::TJsonWriter(IOutputStream* out, bool formatOutput, bool sortkeys, bool validateUtf8)
        : Out(out)
        , Buf(NJsonWriter::HEM_UNSAFE)
        , DoubleNDigits(TJsonWriterConfig::DefaultDoubleNDigits)
        , FloatNDigits(TJsonWriterConfig::DefaultFloatNDigits)
        , FloatToStringMode(TJsonWriterConfig::DefaultFloatToStringMode)
        , SortKeys(sortkeys)
        , ValidateUtf8(validateUtf8)
        , DontEscapeStrings(false)
        , DontFlushInDestructor(false)
    {
        Buf.SetIndentSpaces(formatOutput ? 2 : 0);
    }

    TJsonWriter::TJsonWriter(IOutputStream* out, const TJsonWriterConfig& config, bool DFID)
        : Out(config.Unbuffered ? nullptr : out)
        , Buf(NJsonWriter::HEM_UNSAFE, config.Unbuffered ? out : nullptr)
        , DoubleNDigits(config.DoubleNDigits)
        , FloatNDigits(config.FloatNDigits)
        , FloatToStringMode(config.FloatToStringMode)
        , SortKeys(config.SortKeys)
        , ValidateUtf8(config.ValidateUtf8)
        , DontEscapeStrings(config.DontEscapeStrings)
        , DontFlushInDestructor(DFID)
    {
        Buf.SetIndentSpaces(config.FormatOutput ? 2 : 0);
        Buf.SetWriteNanAsString(config.WriteNanAsString);
    }

    TJsonWriter::~TJsonWriter() {
        // if we write to socket it's possible to get exception here
        // don't use exceptions in destructors
        if (!DontFlushInDestructor) {
            try {
                Flush();
            } catch (...) {
            }
        }
    }

    void TJsonWriter::Flush() {
        if (Out) {
            Buf.FlushTo(Out);
        }
    }

    void TJsonWriter::OpenMap() {
        Buf.BeginObject();
    }

    void TJsonWriter::CloseMap() {
        Buf.EndObject();
    }

    void TJsonWriter::OpenArray() {
        Buf.BeginList();
    }

    void TJsonWriter::CloseArray() {
        Buf.EndList();
    }

    void TJsonWriter::Write(const TStringBuf& value) {
        if (ValidateUtf8 && !IsUtf(value))
            throw yexception() << "JSON writer: invalid UTF-8";
        if (Buf.KeyExpected()) {
            Buf.WriteKey(value);
        } else {
            if (DontEscapeStrings) {
                Buf.UnsafeWriteValue(TString("\"") + value + '"');
            } else {
                Buf.WriteString(value);
            }
        }
    }

    void TJsonWriter::WriteNull() {
        Buf.WriteNull();
    }

    void TJsonWriter::Write(float value) {
        Buf.WriteFloat(value, FloatToStringMode, FloatNDigits);
    }

    void TJsonWriter::Write(double value) {
        Buf.WriteDouble(value, FloatToStringMode, DoubleNDigits);
    }

    void TJsonWriter::Write(long long value) {
        Buf.WriteLongLong(value);
    }

    void TJsonWriter::Write(unsigned long long value) {
        Buf.WriteULongLong(value);
    }

    void TJsonWriter::Write(bool value) {
        Buf.WriteBool(value);
    }

    namespace {
        struct TLessStrPtr {
            bool operator()(const TString* a, const TString* b) const {
                return *a < *b;
            }
        };
    }

    void TJsonWriter::Write(const TJsonValue* v) {
        Buf.WriteJsonValue(v, SortKeys, FloatToStringMode, DoubleNDigits);
    }

    void TJsonWriter::Write(const TJsonValue& v) {
        Buf.WriteJsonValue(&v, SortKeys, FloatToStringMode, DoubleNDigits);
    }

    TString WriteJson(const TJsonValue* value, bool formatOutput, bool sortkeys, bool validateUtf8) {
        TStringStream ss;
        WriteJson(&ss, value, formatOutput, sortkeys, validateUtf8);
        return ss.Str();
    }

    TString WriteJson(const TJsonValue& value, bool formatOutput, bool sortkeys, bool validateUtf8) {
        TStringStream ss;
        WriteJson(&ss, &value, formatOutput, sortkeys, validateUtf8);
        return ss.Str();
    }

    void WriteJson(IOutputStream* out, const TJsonValue* val, bool formatOutput, bool sortkeys, bool validateUtf8) {
        TJsonWriter w(out, formatOutput, sortkeys, validateUtf8);
        w.Write(val);
        w.Flush();
    }

    void WriteJson(IOutputStream* out, const TJsonValue* val, const TJsonWriterConfig& config) {
        TJsonWriter w(out, config, true);
        w.Write(val);
        w.Flush();
    }

}