ClickHouse/src/Functions/FunctionsJSON.cpp

1467 lines
53 KiB
C++

#include <type_traits>
#include <boost/tti/has_member_function.hpp>
#include <base/range.h>
#include <Common/CpuId.h>
#include <Common/typeid_cast.h>
#include <Common/assert_cast.h>
#include <Core/AccurateComparison.h>
#include <Core/Settings.h>
#include <Columns/ColumnConst.h>
#include <Columns/ColumnLowCardinality.h>
#include <Columns/ColumnDecimal.h>
#include <Columns/ColumnString.h>
#include <Columns/ColumnVector.h>
#include <Columns/ColumnFixedString.h>
#include <Columns/ColumnNullable.h>
#include <Columns/ColumnArray.h>
#include <Columns/ColumnTuple.h>
#include <DataTypes/Serializations/SerializationDecimal.h>
#include <DataTypes/DataTypesNumber.h>
#include <DataTypes/DataTypeLowCardinality.h>
#include <DataTypes/DataTypeString.h>
#include <DataTypes/DataTypesDecimal.h>
#include <DataTypes/DataTypeUUID.h>
#include <DataTypes/DataTypeEnum.h>
#include <DataTypes/DataTypeFactory.h>
#include <DataTypes/DataTypeNothing.h>
#include <DataTypes/DataTypeNullable.h>
#include <DataTypes/DataTypeArray.h>
#include <DataTypes/DataTypeTuple.h>
#include <Functions/FunctionFactory.h>
#include <Functions/IFunction.h>
#include <Common/JSONParsers/DummyJSONParser.h>
#include <Common/JSONParsers/SimdJSONParser.h>
#include <Common/JSONParsers/RapidJSONParser.h>
#include <Functions/FunctionHelpers.h>
#include <Interpreters/Context.h>
#include "config_functions.h"
namespace DB
{
namespace ErrorCodes
{
extern const int ILLEGAL_TYPE_OF_ARGUMENT;
extern const int ILLEGAL_COLUMN;
extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
}
template <typename T>
concept HasIndexOperator = requires (T t)
{
t[0];
};
/// Functions to parse JSONs and extract values from it.
/// The first argument of all these functions gets a JSON,
/// after that there are any number of arguments specifying path to a desired part from the JSON's root.
/// For example,
/// select JSONExtractInt('{"a": "hello", "b": [-100, 200.0, 300]}', 'b', 1) = -100
class FunctionJSONHelpers
{
public:
template <typename Name, template<typename> typename Impl, class JSONParser>
class Executor
{
public:
static ColumnPtr run(const ColumnsWithTypeAndName & arguments, const DataTypePtr & result_type, size_t input_rows_count)
{
MutableColumnPtr to{result_type->createColumn()};
to->reserve(input_rows_count);
if (arguments.empty())
throw Exception{"Function " + String(Name::name) + " requires at least one argument", ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH};
const auto & first_column = arguments[0];
if (!isString(first_column.type))
throw Exception{"The first argument of function " + String(Name::name) + " should be a string containing JSON, illegal type: " + first_column.type->getName(),
ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};
const ColumnPtr & arg_json = first_column.column;
const auto * col_json_const = typeid_cast<const ColumnConst *>(arg_json.get());
const auto * col_json_string
= typeid_cast<const ColumnString *>(col_json_const ? col_json_const->getDataColumnPtr().get() : arg_json.get());
if (!col_json_string)
throw Exception{"Illegal column " + arg_json->getName(), ErrorCodes::ILLEGAL_COLUMN};
const ColumnString::Chars & chars = col_json_string->getChars();
const ColumnString::Offsets & offsets = col_json_string->getOffsets();
size_t num_index_arguments = Impl<JSONParser>::getNumberOfIndexArguments(arguments);
std::vector<Move> moves = prepareMoves(Name::name, arguments, 1, num_index_arguments);
/// Preallocate memory in parser if necessary.
JSONParser parser;
if constexpr (has_member_function_reserve<void (JSONParser::*)(size_t)>::value)
{
size_t max_size = calculateMaxSize(offsets);
if (max_size)
parser.reserve(max_size);
}
Impl<JSONParser> impl;
/// prepare() does Impl-specific preparation before handling each row.
if constexpr (has_member_function_prepare<void (Impl<JSONParser>::*)(const char *, const ColumnsWithTypeAndName &, const DataTypePtr &)>::value)
impl.prepare(Name::name, arguments, result_type);
using Element = typename JSONParser::Element;
Element document;
bool document_ok = false;
if (col_json_const)
{
std::string_view json{reinterpret_cast<const char *>(chars.data()), offsets[0] - 1};
document_ok = parser.parse(json, document);
}
for (const auto i : collections::range(0, input_rows_count))
{
if (!col_json_const)
{
std::string_view json{reinterpret_cast<const char *>(&chars[offsets[i - 1]]), offsets[i] - offsets[i - 1] - 1};
document_ok = parser.parse(json, document);
}
bool added_to_column = false;
if (document_ok)
{
/// Perform moves.
Element element;
std::string_view last_key;
bool moves_ok = performMoves<JSONParser>(arguments, i, document, moves, element, last_key);
if (moves_ok)
added_to_column = impl.insertResultToColumn(*to, element, last_key);
}
/// We add default value (=null or zero) if something goes wrong, we don't throw exceptions in these JSON functions.
if (!added_to_column)
to->insertDefault();
}
return to;
}
};
private:
BOOST_TTI_HAS_MEMBER_FUNCTION(reserve)
BOOST_TTI_HAS_MEMBER_FUNCTION(prepare)
/// Represents a move of a JSON iterator described by a single argument passed to a JSON function.
/// For example, the call JSONExtractInt('{"a": "hello", "b": [-100, 200.0, 300]}', 'b', 1)
/// contains two moves: {MoveType::ConstKey, "b"} and {MoveType::ConstIndex, 1}.
/// Keys and indices can be nonconst, in this case they are calculated for each row.
enum class MoveType
{
Key,
Index,
ConstKey,
ConstIndex,
};
struct Move
{
explicit Move(MoveType type_, size_t index_ = 0) : type(type_), index(index_) {}
Move(MoveType type_, const String & key_) : type(type_), key(key_) {}
MoveType type;
size_t index = 0;
String key;
};
static std::vector<FunctionJSONHelpers::Move> prepareMoves(
const char * function_name,
const ColumnsWithTypeAndName & columns,
size_t first_index_argument,
size_t num_index_arguments)
{
std::vector<Move> moves;
moves.reserve(num_index_arguments);
for (const auto i : collections::range(first_index_argument, first_index_argument + num_index_arguments))
{
const auto & column = columns[i];
if (!isString(column.type) && !isInteger(column.type))
throw Exception{"The argument " + std::to_string(i + 1) + " of function " + String(function_name)
+ " should be a string specifying key or an integer specifying index, illegal type: " + column.type->getName(),
ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};
if (column.column && isColumnConst(*column.column))
{
const auto & column_const = assert_cast<const ColumnConst &>(*column.column);
if (isString(column.type))
moves.emplace_back(MoveType::ConstKey, column_const.getValue<String>());
else
moves.emplace_back(MoveType::ConstIndex, column_const.getInt(0));
}
else
{
if (isString(column.type))
moves.emplace_back(MoveType::Key, "");
else
moves.emplace_back(MoveType::Index, 0);
}
}
return moves;
}
/// Performs moves of types MoveType::Index and MoveType::ConstIndex.
template <typename JSONParser>
static bool performMoves(const ColumnsWithTypeAndName & arguments, size_t row,
const typename JSONParser::Element & document, const std::vector<Move> & moves,
typename JSONParser::Element & element, std::string_view & last_key)
{
typename JSONParser::Element res_element = document;
std::string_view key;
for (size_t j = 0; j != moves.size(); ++j)
{
switch (moves[j].type)
{
case MoveType::ConstIndex:
{
if (!moveToElementByIndex<JSONParser>(res_element, moves[j].index, key))
return false;
break;
}
case MoveType::ConstKey:
{
key = moves[j].key;
if (!moveToElementByKey<JSONParser>(res_element, key))
return false;
break;
}
case MoveType::Index:
{
Int64 index = (*arguments[j + 1].column)[row].get<Int64>();
if (!moveToElementByIndex<JSONParser>(res_element, index, key))
return false;
break;
}
case MoveType::Key:
{
key = std::string_view{(*arguments[j + 1].column).getDataAt(row)};
if (!moveToElementByKey<JSONParser>(res_element, key))
return false;
break;
}
}
}
element = res_element;
last_key = key;
return true;
}
template <typename JSONParser>
static bool moveToElementByIndex(typename JSONParser::Element & element, int index, std::string_view & out_key)
{
if (element.isArray())
{
auto array = element.getArray();
if (index >= 0)
--index;
else
index += array.size();
if (static_cast<size_t>(index) >= array.size())
return false;
element = array[index];
out_key = {};
return true;
}
if constexpr (HasIndexOperator<typename JSONParser::Object>)
{
if (element.isObject())
{
auto object = element.getObject();
if (index >= 0)
--index;
else
index += object.size();
if (static_cast<size_t>(index) >= object.size())
return false;
std::tie(out_key, element) = object[index];
return true;
}
}
return {};
}
/// Performs moves of types MoveType::Key and MoveType::ConstKey.
template <typename JSONParser>
static bool moveToElementByKey(typename JSONParser::Element & element, const std::string_view & key)
{
if (!element.isObject())
return false;
auto object = element.getObject();
return object.find(key, element);
}
static size_t calculateMaxSize(const ColumnString::Offsets & offsets)
{
size_t max_size = 0;
for (const auto i : collections::range(0, offsets.size()))
{
size_t size = offsets[i] - offsets[i - 1];
if (max_size < size)
max_size = size;
}
if (max_size)
--max_size;
return max_size;
}
};
template <typename Name, template<typename> typename Impl>
class ExecutableFunctionJSON : public IExecutableFunction, WithContext
{
public:
explicit ExecutableFunctionJSON(const NullPresence & null_presence_, bool allow_simdjson_, const DataTypePtr & json_return_type_)
: null_presence(null_presence_), allow_simdjson(allow_simdjson_), json_return_type(json_return_type_)
{
}
String getName() const override { return Name::name; }
bool useDefaultImplementationForNulls() const override { return false; }
bool useDefaultImplementationForConstants() const override { return true; }
ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr & result_type, size_t input_rows_count) const override
{
if (null_presence.has_null_constant)
return result_type->createColumnConstWithDefaultValue(input_rows_count);
ColumnsWithTypeAndName temporary_columns = null_presence.has_nullable ? createBlockWithNestedColumns(arguments) : arguments;
ColumnPtr temporary_result = chooseAndRunJSONParser(temporary_columns, json_return_type, input_rows_count);
if (null_presence.has_nullable)
return wrapInNullable(temporary_result, arguments, result_type, input_rows_count);
return temporary_result;
}
private:
ColumnPtr
chooseAndRunJSONParser(const ColumnsWithTypeAndName & arguments, const DataTypePtr & result_type, size_t input_rows_count) const
{
#if USE_SIMDJSON
if (allow_simdjson)
return FunctionJSONHelpers::Executor<Name, Impl, SimdJSONParser>::run(arguments, result_type, input_rows_count);
#endif
#if USE_RAPIDJSON
return FunctionJSONHelpers::Executor<Name, Impl, RapidJSONParser>::run(arguments, result_type, input_rows_count);
#else
return FunctionJSONHelpers::Executor<Name, Impl, DummyJSONParser>::run(arguments, result_type, input_rows_count);
#endif
}
NullPresence null_presence;
bool allow_simdjson;
DataTypePtr json_return_type;
};
template <typename Name, template<typename> typename Impl>
class FunctionBaseFunctionJSON : public IFunctionBase
{
public:
explicit FunctionBaseFunctionJSON(
const NullPresence & null_presence_,
bool allow_simdjson_,
DataTypes argument_types_,
DataTypePtr return_type_,
DataTypePtr json_return_type_)
: null_presence(null_presence_)
, allow_simdjson(allow_simdjson_)
, argument_types(std::move(argument_types_))
, return_type(std::move(return_type_))
, json_return_type(std::move(json_return_type_))
{
}
String getName() const override { return Name::name; }
const DataTypes & getArgumentTypes() const override
{
return argument_types;
}
const DataTypePtr & getResultType() const override
{
return return_type;
}
bool isSuitableForShortCircuitArgumentsExecution(const DataTypesWithConstInfo & /*arguments*/) const override { return true; }
ExecutableFunctionPtr prepare(const ColumnsWithTypeAndName &) const override
{
return std::make_unique<ExecutableFunctionJSON<Name, Impl>>(null_presence, allow_simdjson, json_return_type);
}
private:
NullPresence null_presence;
bool allow_simdjson;
DataTypes argument_types;
DataTypePtr return_type;
DataTypePtr json_return_type;
};
/// We use IFunctionOverloadResolver instead of IFunction to handle non-default NULL processing.
/// Both NULL and JSON NULL should generate NULL value. If any argument is NULL, return NULL.
template <typename Name, template<typename> typename Impl>
class JSONOverloadResolver : public IFunctionOverloadResolver, WithContext
{
public:
static constexpr auto name = Name::name;
String getName() const override { return name; }
static FunctionOverloadResolverPtr create(ContextPtr context_)
{
return std::make_unique<JSONOverloadResolver>(context_);
}
explicit JSONOverloadResolver(ContextPtr context_) : WithContext(context_) {}
bool isVariadic() const override { return true; }
size_t getNumberOfArguments() const override { return 0; }
bool useDefaultImplementationForNulls() const override { return false; }
FunctionBasePtr build(const ColumnsWithTypeAndName & arguments) const override
{
bool has_nothing_argument = false;
for (const auto & arg : arguments)
has_nothing_argument |= isNothing(arg.type);
DataTypePtr json_return_type = Impl<DummyJSONParser>::getReturnType(Name::name, createBlockWithNestedColumns(arguments));
NullPresence null_presence = getNullPresense(arguments);
DataTypePtr return_type;
if (has_nothing_argument)
return_type = std::make_shared<DataTypeNothing>();
else if (null_presence.has_null_constant)
return_type = makeNullable(std::make_shared<DataTypeNothing>());
else if (null_presence.has_nullable)
return_type = makeNullable(json_return_type);
else
return_type = json_return_type;
/// Top-level LowCardinality columns are processed outside JSON parser.
json_return_type = removeLowCardinality(json_return_type);
DataTypes argument_types;
argument_types.reserve(arguments.size());
for (const auto & argument : arguments)
argument_types.emplace_back(argument.type);
return std::make_unique<FunctionBaseFunctionJSON<Name, Impl>>(
null_presence, getContext()->getSettingsRef().allow_simdjson, argument_types, return_type, json_return_type);
}
};
struct NameJSONHas { static constexpr auto name{"JSONHas"}; };
struct NameIsValidJSON { static constexpr auto name{"isValidJSON"}; };
struct NameJSONLength { static constexpr auto name{"JSONLength"}; };
struct NameJSONKey { static constexpr auto name{"JSONKey"}; };
struct NameJSONType { static constexpr auto name{"JSONType"}; };
struct NameJSONExtractInt { static constexpr auto name{"JSONExtractInt"}; };
struct NameJSONExtractUInt { static constexpr auto name{"JSONExtractUInt"}; };
struct NameJSONExtractFloat { static constexpr auto name{"JSONExtractFloat"}; };
struct NameJSONExtractBool { static constexpr auto name{"JSONExtractBool"}; };
struct NameJSONExtractString { static constexpr auto name{"JSONExtractString"}; };
struct NameJSONExtract { static constexpr auto name{"JSONExtract"}; };
struct NameJSONExtractKeysAndValues { static constexpr auto name{"JSONExtractKeysAndValues"}; };
struct NameJSONExtractRaw { static constexpr auto name{"JSONExtractRaw"}; };
struct NameJSONExtractArrayRaw { static constexpr auto name{"JSONExtractArrayRaw"}; };
struct NameJSONExtractKeysAndValuesRaw { static constexpr auto name{"JSONExtractKeysAndValuesRaw"}; };
struct NameJSONExtractKeys { static constexpr auto name{"JSONExtractKeys"}; };
template <typename JSONParser>
class JSONHasImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char *, const ColumnsWithTypeAndName &) { return std::make_shared<DataTypeUInt8>(); }
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 1; }
static bool insertResultToColumn(IColumn & dest, const Element &, const std::string_view &)
{
ColumnVector<UInt8> & col_vec = assert_cast<ColumnVector<UInt8> &>(dest);
col_vec.insertValue(1);
return true;
}
};
template <typename JSONParser>
class IsValidJSONImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char * function_name, const ColumnsWithTypeAndName & arguments)
{
if (arguments.size() != 1)
{
/// IsValidJSON() shouldn't get parameters other than JSON.
throw Exception{"Function " + String(function_name) + " needs exactly one argument",
ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH};
}
return std::make_shared<DataTypeUInt8>();
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName &) { return 0; }
static bool insertResultToColumn(IColumn & dest, const Element &, const std::string_view &)
{
/// This function is called only if JSON is valid.
/// If JSON isn't valid then `FunctionJSON::Executor::run()` adds default value (=zero) to `dest` without calling this function.
ColumnVector<UInt8> & col_vec = assert_cast<ColumnVector<UInt8> &>(dest);
col_vec.insertValue(1);
return true;
}
};
template <typename JSONParser>
class JSONLengthImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char *, const ColumnsWithTypeAndName &)
{
return std::make_shared<DataTypeUInt64>();
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 1; }
static bool insertResultToColumn(IColumn & dest, const Element & element, const std::string_view &)
{
size_t size;
if (element.isArray())
size = element.getArray().size();
else if (element.isObject())
size = element.getObject().size();
else
return false;
ColumnVector<UInt64> & col_vec = assert_cast<ColumnVector<UInt64> &>(dest);
col_vec.insertValue(size);
return true;
}
};
template <typename JSONParser>
class JSONKeyImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char *, const ColumnsWithTypeAndName &)
{
return std::make_shared<DataTypeString>();
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 1; }
static bool insertResultToColumn(IColumn & dest, const Element &, const std::string_view & last_key)
{
if (last_key.empty())
return false;
ColumnString & col_str = assert_cast<ColumnString &>(dest);
col_str.insertData(last_key.data(), last_key.size());
return true;
}
};
template <typename JSONParser>
class JSONTypeImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char *, const ColumnsWithTypeAndName &)
{
static const std::vector<std::pair<String, Int8>> values = {
{"Array", '['},
{"Object", '{'},
{"String", '"'},
{"Int64", 'i'},
{"UInt64", 'u'},
{"Double", 'd'},
{"Bool", 'b'},
{"Null", 0}, /// the default value for the column.
};
return std::make_shared<DataTypeEnum<Int8>>(values);
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 1; }
static bool insertResultToColumn(IColumn & dest, const Element & element, const std::string_view &)
{
UInt8 type;
if (element.isInt64())
type = 'i';
else if (element.isUInt64())
type = 'u';
else if (element.isDouble())
type = 'd';
else if (element.isBool())
type = 'b';
else if (element.isString())
type = '"';
else if (element.isArray())
type = '[';
else if (element.isObject())
type = '{';
else if (element.isNull())
type = 0;
else
return false;
ColumnVector<Int8> & col_vec = assert_cast<ColumnVector<Int8> &>(dest);
col_vec.insertValue(type);
return true;
}
};
template <typename JSONParser, typename NumberType, bool convert_bool_to_integer = false>
class JSONExtractNumericImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char *, const ColumnsWithTypeAndName &)
{
return std::make_shared<DataTypeNumber<NumberType>>();
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 1; }
static bool insertResultToColumn(IColumn & dest, const Element & element, const std::string_view &)
{
NumberType value;
if (element.isInt64())
{
if (!accurate::convertNumeric(element.getInt64(), value))
return false;
}
else if (element.isUInt64())
{
if (!accurate::convertNumeric(element.getUInt64(), value))
return false;
}
else if (element.isDouble())
{
if constexpr (std::is_floating_point_v<NumberType>)
{
/// We permit inaccurate conversion of double to float.
/// Example: double 0.1 from JSON is not representable in float.
/// But it will be more convenient for user to perform conversion.
value = element.getDouble();
}
else if (!accurate::convertNumeric(element.getDouble(), value))
return false;
}
else if (element.isBool() && is_integer<NumberType> && convert_bool_to_integer)
{
value = static_cast<NumberType>(element.getBool());
}
else
return false;
auto & col_vec = assert_cast<ColumnVector<NumberType> &>(dest);
col_vec.insertValue(value);
return true;
}
};
template <typename JSONParser>
using JSONExtractInt8Impl = JSONExtractNumericImpl<JSONParser, Int8>;
template <typename JSONParser>
using JSONExtractUInt8Impl = JSONExtractNumericImpl<JSONParser, UInt8>;
template <typename JSONParser>
using JSONExtractInt16Impl = JSONExtractNumericImpl<JSONParser, Int16>;
template <typename JSONParser>
using JSONExtractUInt16Impl = JSONExtractNumericImpl<JSONParser, UInt16>;
template <typename JSONParser>
using JSONExtractInt32Impl = JSONExtractNumericImpl<JSONParser, Int32>;
template <typename JSONParser>
using JSONExtractUInt32Impl = JSONExtractNumericImpl<JSONParser, UInt32>;
template <typename JSONParser>
using JSONExtractInt64Impl = JSONExtractNumericImpl<JSONParser, Int64>;
template <typename JSONParser>
using JSONExtractUInt64Impl = JSONExtractNumericImpl<JSONParser, UInt64>;
template <typename JSONParser>
using JSONExtractFloat32Impl = JSONExtractNumericImpl<JSONParser, Float32>;
template <typename JSONParser>
using JSONExtractFloat64Impl = JSONExtractNumericImpl<JSONParser, Float64>;
template <typename JSONParser>
class JSONExtractBoolImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char *, const ColumnsWithTypeAndName &)
{
return std::make_shared<DataTypeUInt8>();
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 1; }
static bool insertResultToColumn(IColumn & dest, const Element & element, const std::string_view &)
{
if (!element.isBool())
return false;
auto & col_vec = assert_cast<ColumnVector<UInt8> &>(dest);
col_vec.insertValue(static_cast<UInt8>(element.getBool()));
return true;
}
};
template <typename JSONParser>
class JSONExtractRawImpl;
template <typename JSONParser>
class JSONExtractStringImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char *, const ColumnsWithTypeAndName &)
{
return std::make_shared<DataTypeString>();
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 1; }
static bool insertResultToColumn(IColumn & dest, const Element & element, const std::string_view &)
{
if (element.isNull())
return false;
if (!element.isString())
return JSONExtractRawImpl<JSONParser>::insertResultToColumn(dest, element, {});
auto str = element.getString();
ColumnString & col_str = assert_cast<ColumnString &>(dest);
col_str.insertData(str.data(), str.size());
return true;
}
};
/// Nodes of the extract tree. We need the extract tree to extract from JSON complex values containing array, tuples or nullables.
template <typename JSONParser>
struct JSONExtractTree
{
using Element = typename JSONParser::Element;
class Node
{
public:
Node() = default;
virtual ~Node() = default;
virtual bool insertResultToColumn(IColumn &, const Element &) = 0;
};
template <typename NumberType>
class NumericNode : public Node
{
public:
bool insertResultToColumn(IColumn & dest, const Element & element) override
{
return JSONExtractNumericImpl<JSONParser, NumberType, true>::insertResultToColumn(dest, element, {});
}
};
class LowCardinalityNode : public Node
{
public:
LowCardinalityNode(DataTypePtr dictionary_type_, std::unique_ptr<Node> impl_)
: dictionary_type(dictionary_type_), impl(std::move(impl_)) {}
bool insertResultToColumn(IColumn & dest, const Element & element) override
{
auto from_col = dictionary_type->createColumn();
if (impl->insertResultToColumn(*from_col, element))
{
StringRef value = from_col->getDataAt(0);
assert_cast<ColumnLowCardinality &>(dest).insertData(value.data, value.size);
return true;
}
return false;
}
private:
DataTypePtr dictionary_type;
std::unique_ptr<Node> impl;
};
class UUIDNode : public Node
{
public:
bool insertResultToColumn(IColumn & dest, const Element & element) override
{
if (!element.isString())
return false;
auto uuid = parseFromString<UUID>(element.getString());
assert_cast<ColumnUUID &>(dest).insert(uuid);
return true;
}
};
template <typename DecimalType>
class DecimalNode : public Node
{
public:
explicit DecimalNode(DataTypePtr data_type_) : data_type(data_type_) {}
bool insertResultToColumn(IColumn & dest, const Element & element) override
{
if (!element.isDouble())
return false;
const auto * type = assert_cast<const DataTypeDecimal<DecimalType> *>(data_type.get());
auto result = convertToDecimal<DataTypeNumber<Float64>, DataTypeDecimal<DecimalType>>(element.getDouble(), type->getScale());
assert_cast<ColumnDecimal<DecimalType> &>(dest).insert(result);
return true;
}
private:
DataTypePtr data_type;
};
class StringNode : public Node
{
public:
bool insertResultToColumn(IColumn & dest, const Element & element) override
{
return JSONExtractStringImpl<JSONParser>::insertResultToColumn(dest, element, {});
}
};
class FixedStringNode : public Node
{
public:
bool insertResultToColumn(IColumn & dest, const Element & element) override
{
if (!element.isString())
return false;
auto & col_str = assert_cast<ColumnFixedString &>(dest);
auto str = element.getString();
if (str.size() > col_str.getN())
return false;
col_str.insertData(str.data(), str.size());
return true;
}
};
template <typename Type>
class EnumNode : public Node
{
public:
explicit EnumNode(const std::vector<std::pair<String, Type>> & name_value_pairs_) : name_value_pairs(name_value_pairs_)
{
for (const auto & name_value_pair : name_value_pairs)
{
name_to_value_map.emplace(name_value_pair.first, name_value_pair.second);
only_values.emplace(name_value_pair.second);
}
}
bool insertResultToColumn(IColumn & dest, const Element & element) override
{
auto & col_vec = assert_cast<ColumnVector<Type> &>(dest);
if (element.isInt64())
{
Type value;
if (!accurate::convertNumeric(element.getInt64(), value) || !only_values.contains(value))
return false;
col_vec.insertValue(value);
return true;
}
if (element.isUInt64())
{
Type value;
if (!accurate::convertNumeric(element.getUInt64(), value) || !only_values.contains(value))
return false;
col_vec.insertValue(value);
return true;
}
if (element.isString())
{
auto value = name_to_value_map.find(element.getString());
if (value == name_to_value_map.end())
return false;
col_vec.insertValue(value->second);
return true;
}
return false;
}
private:
std::vector<std::pair<String, Type>> name_value_pairs;
std::unordered_map<std::string_view, Type> name_to_value_map;
std::unordered_set<Type> only_values;
};
class NullableNode : public Node
{
public:
explicit NullableNode(std::unique_ptr<Node> nested_) : nested(std::move(nested_)) {}
bool insertResultToColumn(IColumn & dest, const Element & element) override
{
ColumnNullable & col_null = assert_cast<ColumnNullable &>(dest);
if (!nested->insertResultToColumn(col_null.getNestedColumn(), element))
return false;
col_null.getNullMapColumn().insertValue(0);
return true;
}
private:
std::unique_ptr<Node> nested;
};
class ArrayNode : public Node
{
public:
explicit ArrayNode(std::unique_ptr<Node> nested_) : nested(std::move(nested_)) {}
bool insertResultToColumn(IColumn & dest, const Element & element) override
{
if (!element.isArray())
return false;
auto array = element.getArray();
ColumnArray & col_arr = assert_cast<ColumnArray &>(dest);
auto & data = col_arr.getData();
size_t old_size = data.size();
bool were_valid_elements = false;
for (auto value : array)
{
if (nested->insertResultToColumn(data, value))
were_valid_elements = true;
else
data.insertDefault();
}
if (!were_valid_elements)
{
data.popBack(data.size() - old_size);
return false;
}
col_arr.getOffsets().push_back(data.size());
return true;
}
private:
std::unique_ptr<Node> nested;
};
class TupleNode : public Node
{
public:
TupleNode(std::vector<std::unique_ptr<Node>> nested_, const std::vector<String> & explicit_names_) : nested(std::move(nested_)), explicit_names(explicit_names_)
{
for (size_t i = 0; i != explicit_names.size(); ++i)
name_to_index_map.emplace(explicit_names[i], i);
}
bool insertResultToColumn(IColumn & dest, const Element & element) override
{
ColumnTuple & tuple = assert_cast<ColumnTuple &>(dest);
size_t old_size = dest.size();
bool were_valid_elements = false;
auto set_size = [&](size_t size)
{
for (size_t i = 0; i != tuple.tupleSize(); ++i)
{
auto & col = tuple.getColumn(i);
if (col.size() != size)
{
if (col.size() > size)
col.popBack(col.size() - size);
else
while (col.size() < size)
col.insertDefault();
}
}
};
if (element.isArray())
{
auto array = element.getArray();
auto it = array.begin();
for (size_t index = 0; (index != nested.size()) && (it != array.end()); ++index)
{
if (nested[index]->insertResultToColumn(tuple.getColumn(index), *it++))
were_valid_elements = true;
else
tuple.getColumn(index).insertDefault();
}
set_size(old_size + static_cast<size_t>(were_valid_elements));
return were_valid_elements;
}
if (element.isObject())
{
auto object = element.getObject();
if (name_to_index_map.empty())
{
auto it = object.begin();
for (size_t index = 0; (index != nested.size()) && (it != object.end()); ++index)
{
if (nested[index]->insertResultToColumn(tuple.getColumn(index), (*it++).second))
were_valid_elements = true;
else
tuple.getColumn(index).insertDefault();
}
}
else
{
for (const auto & [key, value] : object)
{
auto index = name_to_index_map.find(key);
if (index != name_to_index_map.end())
{
if (nested[index->second]->insertResultToColumn(tuple.getColumn(index->second), value))
were_valid_elements = true;
}
}
}
set_size(old_size + static_cast<size_t>(were_valid_elements));
return were_valid_elements;
}
return false;
}
private:
std::vector<std::unique_ptr<Node>> nested;
std::vector<String> explicit_names;
std::unordered_map<std::string_view, size_t> name_to_index_map;
};
static std::unique_ptr<Node> build(const char * function_name, const DataTypePtr & type)
{
switch (type->getTypeId())
{
case TypeIndex::UInt8: return std::make_unique<NumericNode<UInt8>>();
case TypeIndex::UInt16: return std::make_unique<NumericNode<UInt16>>();
case TypeIndex::UInt32: return std::make_unique<NumericNode<UInt32>>();
case TypeIndex::UInt64: return std::make_unique<NumericNode<UInt64>>();
case TypeIndex::Int8: return std::make_unique<NumericNode<Int8>>();
case TypeIndex::Int16: return std::make_unique<NumericNode<Int16>>();
case TypeIndex::Int32: return std::make_unique<NumericNode<Int32>>();
case TypeIndex::Int64: return std::make_unique<NumericNode<Int64>>();
case TypeIndex::Float32: return std::make_unique<NumericNode<Float32>>();
case TypeIndex::Float64: return std::make_unique<NumericNode<Float64>>();
case TypeIndex::String: return std::make_unique<StringNode>();
case TypeIndex::FixedString: return std::make_unique<FixedStringNode>();
case TypeIndex::UUID: return std::make_unique<UUIDNode>();
case TypeIndex::LowCardinality:
{
auto dictionary_type = typeid_cast<const DataTypeLowCardinality *>(type.get())->getDictionaryType();
auto impl = build(function_name, dictionary_type);
return std::make_unique<LowCardinalityNode>(dictionary_type, std::move(impl));
}
case TypeIndex::Decimal256: return std::make_unique<DecimalNode<Decimal256>>(type);
case TypeIndex::Decimal128: return std::make_unique<DecimalNode<Decimal128>>(type);
case TypeIndex::Decimal64: return std::make_unique<DecimalNode<Decimal64>>(type);
case TypeIndex::Decimal32: return std::make_unique<DecimalNode<Decimal32>>(type);
case TypeIndex::Enum8:
return std::make_unique<EnumNode<Int8>>(static_cast<const DataTypeEnum8 &>(*type).getValues());
case TypeIndex::Enum16:
return std::make_unique<EnumNode<Int16>>(static_cast<const DataTypeEnum16 &>(*type).getValues());
case TypeIndex::Nullable:
{
return std::make_unique<NullableNode>(build(function_name, static_cast<const DataTypeNullable &>(*type).getNestedType()));
}
case TypeIndex::Array:
{
return std::make_unique<ArrayNode>(build(function_name, static_cast<const DataTypeArray &>(*type).getNestedType()));
}
case TypeIndex::Tuple:
{
const auto & tuple = static_cast<const DataTypeTuple &>(*type);
const auto & tuple_elements = tuple.getElements();
std::vector<std::unique_ptr<Node>> elements;
elements.reserve(tuple_elements.size());
for (const auto & tuple_element : tuple_elements)
elements.emplace_back(build(function_name, tuple_element));
return std::make_unique<TupleNode>(std::move(elements), tuple.haveExplicitNames() ? tuple.getElementNames() : Strings{});
}
default:
throw Exception{"Function " + String(function_name) + " doesn't support the return type schema: " + type->getName(), ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};
}
}
};
template <typename JSONParser>
class JSONExtractImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char * function_name, const ColumnsWithTypeAndName & arguments)
{
if (arguments.size() < 2)
throw Exception{"Function " + String(function_name) + " requires at least two arguments", ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH};
const auto & col = arguments.back();
const auto * col_type_const = typeid_cast<const ColumnConst *>(col.column.get());
if (!col_type_const || !isString(col.type))
throw Exception{"The last argument of function " + String(function_name)
+ " should be a constant string specifying the return data type, illegal value: " + col.name,
ErrorCodes::ILLEGAL_COLUMN};
return DataTypeFactory::instance().get(col_type_const->getValue<String>());
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 2; }
void prepare(const char * function_name, const ColumnsWithTypeAndName &, const DataTypePtr & result_type)
{
extract_tree = JSONExtractTree<JSONParser>::build(function_name, result_type);
}
bool insertResultToColumn(IColumn & dest, const Element & element, const std::string_view &)
{
return extract_tree->insertResultToColumn(dest, element);
}
protected:
std::unique_ptr<typename JSONExtractTree<JSONParser>::Node> extract_tree;
};
template <typename JSONParser>
class JSONExtractKeysAndValuesImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char * function_name, const ColumnsWithTypeAndName & arguments)
{
if (arguments.size() < 2)
throw Exception{"Function " + String(function_name) + " requires at least two arguments", ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH};
const auto & col = arguments.back();
const auto * col_type_const = typeid_cast<const ColumnConst *>(col.column.get());
if (!col_type_const || !isString(col.type))
throw Exception{"The last argument of function " + String(function_name)
+ " should be a constant string specifying the values' data type, illegal value: " + col.name,
ErrorCodes::ILLEGAL_COLUMN};
DataTypePtr key_type = std::make_unique<DataTypeString>();
DataTypePtr value_type = DataTypeFactory::instance().get(col_type_const->getValue<String>());
DataTypePtr tuple_type = std::make_unique<DataTypeTuple>(DataTypes{key_type, value_type});
return std::make_unique<DataTypeArray>(tuple_type);
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 2; }
void prepare(const char * function_name, const ColumnsWithTypeAndName &, const DataTypePtr & result_type)
{
const auto tuple_type = typeid_cast<const DataTypeArray *>(result_type.get())->getNestedType();
const auto value_type = typeid_cast<const DataTypeTuple *>(tuple_type.get())->getElements()[1];
extract_tree = JSONExtractTree<JSONParser>::build(function_name, value_type);
}
bool insertResultToColumn(IColumn & dest, const Element & element, const std::string_view &)
{
if (!element.isObject())
return false;
auto object = element.getObject();
auto & col_arr = assert_cast<ColumnArray &>(dest);
auto & col_tuple = assert_cast<ColumnTuple &>(col_arr.getData());
size_t old_size = col_tuple.size();
auto & col_key = assert_cast<ColumnString &>(col_tuple.getColumn(0));
auto & col_value = col_tuple.getColumn(1);
for (const auto & [key, value] : object)
{
if (extract_tree->insertResultToColumn(col_value, value))
col_key.insertData(key.data(), key.size());
}
if (col_tuple.size() == old_size)
return false;
col_arr.getOffsets().push_back(col_tuple.size());
return true;
}
private:
std::unique_ptr<typename JSONExtractTree<JSONParser>::Node> extract_tree;
};
template <typename JSONParser>
class JSONExtractRawImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char *, const ColumnsWithTypeAndName &)
{
return std::make_shared<DataTypeString>();
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 1; }
static bool insertResultToColumn(IColumn & dest, const Element & element, const std::string_view &)
{
ColumnString & col_str = assert_cast<ColumnString &>(dest);
auto & chars = col_str.getChars();
WriteBufferFromVector<ColumnString::Chars> buf(chars, AppendModeTag());
traverse(element, buf);
buf.finalize();
chars.push_back(0);
col_str.getOffsets().push_back(chars.size());
return true;
}
private:
static void traverse(const Element & element, WriteBuffer & buf)
{
if (element.isInt64())
{
writeIntText(element.getInt64(), buf);
return;
}
if (element.isUInt64())
{
writeIntText(element.getUInt64(), buf);
return;
}
if (element.isDouble())
{
writeFloatText(element.getDouble(), buf);
return;
}
if (element.isBool())
{
if (element.getBool())
writeCString("true", buf);
else
writeCString("false", buf);
return;
}
if (element.isString())
{
writeJSONString(element.getString(), buf, formatSettings());
return;
}
if (element.isArray())
{
writeChar('[', buf);
bool need_comma = false;
for (auto value : element.getArray())
{
if (std::exchange(need_comma, true))
writeChar(',', buf);
traverse(value, buf);
}
writeChar(']', buf);
return;
}
if (element.isObject())
{
writeChar('{', buf);
bool need_comma = false;
for (auto [key, value] : element.getObject())
{
if (std::exchange(need_comma, true))
writeChar(',', buf);
writeJSONString(key, buf, formatSettings());
writeChar(':', buf);
traverse(value, buf);
}
writeChar('}', buf);
return;
}
if (element.isNull())
{
writeCString("null", buf);
return;
}
}
static const FormatSettings & formatSettings()
{
static const FormatSettings the_instance = []
{
FormatSettings settings;
settings.json.escape_forward_slashes = false;
return settings;
}();
return the_instance;
}
};
template <typename JSONParser>
class JSONExtractArrayRawImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char *, const ColumnsWithTypeAndName &)
{
return std::make_shared<DataTypeArray>(std::make_shared<DataTypeString>());
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 1; }
static bool insertResultToColumn(IColumn & dest, const Element & element, const std::string_view &)
{
if (!element.isArray())
return false;
auto array = element.getArray();
ColumnArray & col_res = assert_cast<ColumnArray &>(dest);
for (auto value : array)
JSONExtractRawImpl<JSONParser>::insertResultToColumn(col_res.getData(), value, {});
col_res.getOffsets().push_back(col_res.getOffsets().back() + array.size());
return true;
}
};
template <typename JSONParser>
class JSONExtractKeysAndValuesRawImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char *, const ColumnsWithTypeAndName &)
{
DataTypePtr string_type = std::make_unique<DataTypeString>();
DataTypePtr tuple_type = std::make_unique<DataTypeTuple>(DataTypes{string_type, string_type});
return std::make_unique<DataTypeArray>(tuple_type);
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 1; }
bool insertResultToColumn(IColumn & dest, const Element & element, const std::string_view &)
{
if (!element.isObject())
return false;
auto object = element.getObject();
auto & col_arr = assert_cast<ColumnArray &>(dest);
auto & col_tuple = assert_cast<ColumnTuple &>(col_arr.getData());
auto & col_key = assert_cast<ColumnString &>(col_tuple.getColumn(0));
auto & col_value = assert_cast<ColumnString &>(col_tuple.getColumn(1));
for (const auto & [key, value] : object)
{
col_key.insertData(key.data(), key.size());
JSONExtractRawImpl<JSONParser>::insertResultToColumn(col_value, value, {});
}
col_arr.getOffsets().push_back(col_arr.getOffsets().back() + object.size());
return true;
}
};
template <typename JSONParser>
class JSONExtractKeysImpl
{
public:
using Element = typename JSONParser::Element;
static DataTypePtr getReturnType(const char *, const ColumnsWithTypeAndName &)
{
return std::make_unique<DataTypeArray>(std::make_shared<DataTypeString>());
}
static size_t getNumberOfIndexArguments(const ColumnsWithTypeAndName & arguments) { return arguments.size() - 1; }
bool insertResultToColumn(IColumn & dest, const Element & element, const std::string_view &)
{
if (!element.isObject())
return false;
auto object = element.getObject();
ColumnArray & col_res = assert_cast<ColumnArray &>(dest);
auto & col_key = assert_cast<ColumnString &>(col_res.getData());
for (const auto & [key, value] : object)
{
col_key.insertData(key.data(), key.size());
}
col_res.getOffsets().push_back(col_res.getOffsets().back() + object.size());
return true;
}
};
void registerFunctionsJSON(FunctionFactory & factory)
{
factory.registerFunction<JSONOverloadResolver<NameJSONHas, JSONHasImpl>>();
factory.registerFunction<JSONOverloadResolver<NameIsValidJSON, IsValidJSONImpl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONLength, JSONLengthImpl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONKey, JSONKeyImpl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONType, JSONTypeImpl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONExtractInt, JSONExtractInt64Impl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONExtractUInt, JSONExtractUInt64Impl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONExtractFloat, JSONExtractFloat64Impl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONExtractBool, JSONExtractBoolImpl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONExtractString, JSONExtractStringImpl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONExtract, JSONExtractImpl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONExtractKeysAndValues, JSONExtractKeysAndValuesImpl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONExtractRaw, JSONExtractRawImpl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONExtractArrayRaw, JSONExtractArrayRawImpl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONExtractKeysAndValuesRaw, JSONExtractKeysAndValuesRawImpl>>();
factory.registerFunction<JSONOverloadResolver<NameJSONExtractKeys, JSONExtractKeysImpl>>();
}
}