utils_json.h

Go to the documentation of this file.

/*
 * Copyright (c) 2015, 2025, Oracle and/or its affiliates.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2.0,
 * as published by the Free Software Foundation.
 *
 * This program is designed to work with certain software (including
 * but not limited to OpenSSL) that is licensed under separate terms,
 * as designated in a particular file or component or in included license
 * documentation.  The authors of MySQL hereby grant you an additional
 * permission to link the program and your derivative works with the
 * separately licensed software that they have either included with
 * the program or referenced in the documentation.
 *
 * This program is distributed in the hope that it will be useful,  but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 * the GNU General Public License, version 2.0, for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */
 
#ifndef MYSQLSHDK_LIBS_UTILS_UTILS_JSON_H_
#define MYSQLSHDK_LIBS_UTILS_UTILS_JSON_H_
 
#ifdef RAPIDJSON_NO_SIZETYPEDEFINE
#include "my_rapidjson_size_t.h"
#endif
 
#include <rapidjson/rapidjson.h>
 
#include <rapidjson/document.h>
 
#include <cstdint>
#include <memory>
#include <optional>
#include <string>
#include <string_view>
 
// #include "mysqlshdk/include/mysqlshdk_export.h"
// #include "mysqlshdk/include/scripting/types.h"
#include "mysqlrouter/jit_executor_value.h"
 
namespace shcore {
 
class /*SHCORE_PUBLIC*/ JSON_dumper final {
 public:
  class Writer_base;
 
  explicit JSON_dumper(bool pprint = false, size_t binary_limit = 0);
  ~JSON_dumper();
 
  void start_array();
  void end_array();
  void start_object();
  void end_object();
 
  void append_value(const Value &value);
  void append_value(std::string_view key, const Value &value);
  void append(const Value &value);
  void append(std::string_view key, const Value &value);
 
  void append(const Dictionary_t &value);
  void append(std::string_view key, const Dictionary_t &value);
 
  void append(const Array_t &value);
  void append(std::string_view key, const Array_t &value);
 
  void append_null() const;
  void append_null(std::string_view key) const;
 
  void append_bool(bool data) const;
  void append_bool(std::string_view key, bool data) const;
  void append(bool data) const;
  void append(std::string_view key, bool data) const;
 
  void append_int(int data) const;
  void append_int(std::string_view key, int data) const;
  void append(int data) const;
  void append(std::string_view key, int data) const;
 
  void append_uint(unsigned int data) const;
  void append_uint(std::string_view key, unsigned int data) const;
  void append(unsigned int data) const;
  void append(std::string_view key, unsigned int data) const;
 
  void append_int64(int64_t data) const;
  void append_int64(std::string_view key, int64_t data) const;
 
  void append_uint64(uint64_t data) const;
  void append_uint64(std::string_view key, uint64_t data) const;
 
  void append(long int data) const;
  void append(std::string_view key, long int data) const;
 
  void append(unsigned long int data) const;
  void append(std::string_view key, unsigned long int data) const;
 
  void append(long long int data) const;
  void append(std::string_view key, long long int data) const;
 
  void append(unsigned long long int data) const;
  void append(std::string_view key, unsigned long long int data) const;
 
  void append_string(std::string_view data) const;
  void append_string(std::string_view key, std::string_view data) const;
  void append(std::string_view data) const;
  inline void append(const char *data) const { append_string(data); }
  void append(std::string_view key, std::string_view data) const;
  inline void append(std::string_view key, const char *data) const {
    append_string(key, data);
  }
 
  void append_float(double data) const;
  void append_float(std::string_view key, double data) const;
  void append(double data) const;
  void append(std::string_view key, double data) const;
 
  void append_json(const std::string &data) const;
 
  int deep_level() const { return _deep_level; }
 
  const std::string &str() const;
 
 private:
  int _deep_level{0};
  size_t _binary_limit{0};
 
  std::unique_ptr<Writer_base> _writer;
};
 
namespace json {
 
using JSON = rapidjson::Document;
 
/**
 * Parses a JSON string.
 *
 * NOTE: this does not throw exceptions, parsed document can be potentially
 * invalid.
 *
 * @param json JSON to be parsed.
 *
 * @returns parsed document
 */
JSON parse(std::string_view json);
 
/**
 * Parses a JSON string, input is expected to be a JSON object.
 *
 * @param json JSON to be parsed.
 *
 * @returns parsed document
 *
 * @throws std::runtime_error if parsing fails, or result is not a JSON object.
 */
JSON parse_object_or_throw(std::string_view json);
 
/**
 * Fetches a string value of a required field.
 *
 * @param json JSON object.
 * @param name Name of the field.
 * @param allow_empty Don't throw if value is an empty string.
 *
 * @returns string value
 *
 * @throws std::runtime_error if field does not exist or its value is not a
 * string
 */
std::string required(const JSON &json, const char *name,
                     bool allow_empty = false);
 
/**
 * Fetches an unsigned integer value of a required field.
 *
 * @param json JSON object.
 * @param name Name of the field.
 *
 * @returns unsigned integer value
 *
 * @throws std::runtime_error if field does not exist or its value is not an
 * unsigned integer
 */
uint64_t required_uint(const JSON &json, const char *name);
 
/**
 * Fetches a string value of an optional field.
 *
 * @param json JSON object.
 * @param name Name of the field.
 * @param allow_empty Don't throw if value is an empty string.
 *
 * @returns string value if JSON contains the specified field
 *
 * @throws std::runtime_error if value is not a string
 */
std::optional<std::string> optional(const JSON &json, const char *name,
                                    bool allow_empty = false);
 
/**
 * Fetches an unsigned integer value of an optional field.
 *
 * @param json JSON object.
 * @param name Name of the field.
 *
 * @returns unsigned integer value if JSON contains the specified field
 *
 * @throws std::runtime_error if value is not an unsigned integer
 */
std::optional<uint64_t> optional_uint(const JSON &json, const char *name);
 
/**
 * Converts a JSON object to a string.
 *
 * @param json A JSON object
 *
 * @returns String representation of a JSON object.
 */
std::string to_string(const JSON &json);
 
/**
 * Converts a JSON object to a nicely formatted string.
 *
 * @param json A JSON object
 *
 * @returns String representation of a JSON object.
 */
std::string to_pretty_string(const JSON &json);
 
}  // namespace json
 
}  // namespace shcore
 
#endif  // MYSQLSHDK_LIBS_UTILS_UTILS_JSON_H_