memgraph/src/storage/v2/property_value.hpp

447 lines
14 KiB
C++

#pragma once
#include <iostream>
#include <map>
#include <string>
#include <vector>
#include "utils/algorithm.hpp"
#include "utils/exceptions.hpp"
namespace storage {
/// An exception raised by the PropertyValue. Typically when trying to perform
/// operations (such as addition) on PropertyValues of incompatible Types.
class PropertyValueException : public utils::BasicException {
public:
using utils::BasicException::BasicException;
};
/// Encapsulation of a value and its type in a class that has no compile-time
/// info about the type.
///
/// Values can be of a number of predefined types that are enumerated in
/// PropertyValue::Type. Each such type corresponds to exactly one C++ type.
class PropertyValue {
public:
/// A value type, each type corresponds to exactly one C++ type.
enum class Type : uint8_t {
Null = 0,
Bool = 1,
Int = 2,
Double = 3,
String = 4,
List = 5,
Map = 6,
};
static bool AreComparableTypes(Type a, Type b) {
return (a == b) || (a == Type::Int && b == Type::Double) || (a == Type::Double && b == Type::Int);
}
/// Make a Null value
PropertyValue() : type_(Type::Null) {}
// constructors for primitive types
explicit PropertyValue(bool value) : type_(Type::Bool) { bool_v = value; }
explicit PropertyValue(int value) : type_(Type::Int) { int_v = value; }
explicit PropertyValue(int64_t value) : type_(Type::Int) { int_v = value; }
explicit PropertyValue(double value) : type_(Type::Double) { double_v = value; }
// copy constructors for non-primitive types
/// @throw std::bad_alloc
explicit PropertyValue(const std::string &value) : type_(Type::String) { new (&string_v) std::string(value); }
/// @throw std::bad_alloc
/// @throw std::length_error if length of value exceeds
/// std::string::max_length().
explicit PropertyValue(const char *value) : type_(Type::String) { new (&string_v) std::string(value); }
/// @throw std::bad_alloc
explicit PropertyValue(const std::vector<PropertyValue> &value) : type_(Type::List) {
new (&list_v) std::vector<PropertyValue>(value);
}
/// @throw std::bad_alloc
explicit PropertyValue(const std::map<std::string, PropertyValue> &value) : type_(Type::Map) {
new (&map_v) std::map<std::string, PropertyValue>(value);
}
// move constructors for non-primitive types
explicit PropertyValue(std::string &&value) noexcept : type_(Type::String) {
new (&string_v) std::string(std::move(value));
}
explicit PropertyValue(std::vector<PropertyValue> &&value) noexcept : type_(Type::List) {
new (&list_v) std::vector<PropertyValue>(std::move(value));
}
explicit PropertyValue(std::map<std::string, PropertyValue> &&value) noexcept : type_(Type::Map) {
new (&map_v) std::map<std::string, PropertyValue>(std::move(value));
}
// copy constructor
/// @throw std::bad_alloc
PropertyValue(const PropertyValue &other);
// move constructor
PropertyValue(PropertyValue &&other) noexcept;
// copy assignment
/// @throw std::bad_alloc
PropertyValue &operator=(const PropertyValue &other);
// move assignment
PropertyValue &operator=(PropertyValue &&other) noexcept;
// TODO: Implement copy assignment operators for primitive types.
// TODO: Implement copy and move assignment operators for non-primitive types.
~PropertyValue() { DestroyValue(); }
Type type() const { return type_; }
// type checkers
bool IsNull() const { return type_ == Type::Null; }
bool IsBool() const { return type_ == Type::Bool; }
bool IsInt() const { return type_ == Type::Int; }
bool IsDouble() const { return type_ == Type::Double; }
bool IsString() const { return type_ == Type::String; }
bool IsList() const { return type_ == Type::List; }
bool IsMap() const { return type_ == Type::Map; }
// value getters for primitive types
/// @throw PropertyValueException if value isn't of correct type.
bool ValueBool() const {
if (type_ != Type::Bool) {
throw PropertyValueException("The value isn't a bool!");
}
return bool_v;
}
/// @throw PropertyValueException if value isn't of correct type.
int64_t ValueInt() const {
if (type_ != Type::Int) {
throw PropertyValueException("The value isn't an int!");
}
return int_v;
}
/// @throw PropertyValueException if value isn't of correct type.
double ValueDouble() const {
if (type_ != Type::Double) {
throw PropertyValueException("The value isn't a double!");
}
return double_v;
}
// const value getters for non-primitive types
/// @throw PropertyValueException if value isn't of correct type.
const std::string &ValueString() const {
if (type_ != Type::String) {
throw PropertyValueException("The value isn't a string!");
}
return string_v;
}
/// @throw PropertyValueException if value isn't of correct type.
const std::vector<PropertyValue> &ValueList() const {
if (type_ != Type::List) {
throw PropertyValueException("The value isn't a list!");
}
return list_v;
}
/// @throw PropertyValueException if value isn't of correct type.
const std::map<std::string, PropertyValue> &ValueMap() const {
if (type_ != Type::Map) {
throw PropertyValueException("The value isn't a map!");
}
return map_v;
}
// reference value getters for non-primitive types
/// @throw PropertyValueException if value isn't of correct type.
std::string &ValueString() {
if (type_ != Type::String) {
throw PropertyValueException("The value isn't a string!");
}
return string_v;
}
/// @throw PropertyValueException if value isn't of correct type.
std::vector<PropertyValue> &ValueList() {
if (type_ != Type::List) {
throw PropertyValueException("The value isn't a list!");
}
return list_v;
}
/// @throw PropertyValueException if value isn't of correct type.
std::map<std::string, PropertyValue> &ValueMap() {
if (type_ != Type::Map) {
throw PropertyValueException("The value isn't a map!");
}
return map_v;
}
private:
void DestroyValue() noexcept;
union {
bool bool_v;
int64_t int_v;
double double_v;
std::string string_v;
std::vector<PropertyValue> list_v;
std::map<std::string, PropertyValue> map_v;
};
Type type_;
};
// stream output
/// @throw anything std::ostream::operator<< may throw.
inline std::ostream &operator<<(std::ostream &os, const PropertyValue::Type type) {
switch (type) {
case PropertyValue::Type::Null:
return os << "null";
case PropertyValue::Type::Bool:
return os << "bool";
case PropertyValue::Type::Int:
return os << "int";
case PropertyValue::Type::Double:
return os << "double";
case PropertyValue::Type::String:
return os << "string";
case PropertyValue::Type::List:
return os << "list";
case PropertyValue::Type::Map:
return os << "map";
}
}
/// @throw anything std::ostream::operator<< may throw.
inline std::ostream &operator<<(std::ostream &os, const PropertyValue &value) {
switch (value.type()) {
case PropertyValue::Type::Null:
return os << "null";
case PropertyValue::Type::Bool:
return os << (value.ValueBool() ? "true" : "false");
case PropertyValue::Type::Int:
return os << value.ValueInt();
case PropertyValue::Type::Double:
return os << value.ValueDouble();
case PropertyValue::Type::String:
return os << value.ValueString();
case PropertyValue::Type::List:
os << "[";
utils::PrintIterable(os, value.ValueList());
return os << "]";
case PropertyValue::Type::Map:
os << "{";
utils::PrintIterable(os, value.ValueMap(), ", ",
[](auto &stream, const auto &pair) { stream << pair.first << ": " << pair.second; });
return os << "}";
}
}
// NOTE: The logic in this function *MUST* be equal to the logic in
// `PropertyStore::ComparePropertyValue`. If you change this operator make sure
// to change the function so that they have identical functionality.
inline bool operator==(const PropertyValue &first, const PropertyValue &second) noexcept {
if (!PropertyValue::AreComparableTypes(first.type(), second.type())) return false;
switch (first.type()) {
case PropertyValue::Type::Null:
return true;
case PropertyValue::Type::Bool:
return first.ValueBool() == second.ValueBool();
case PropertyValue::Type::Int:
if (second.type() == PropertyValue::Type::Double) {
return first.ValueInt() == second.ValueDouble();
} else {
return first.ValueInt() == second.ValueInt();
}
case PropertyValue::Type::Double:
if (second.type() == PropertyValue::Type::Double) {
return first.ValueDouble() == second.ValueDouble();
} else {
return first.ValueDouble() == second.ValueInt();
}
case PropertyValue::Type::String:
return first.ValueString() == second.ValueString();
case PropertyValue::Type::List:
return first.ValueList() == second.ValueList();
case PropertyValue::Type::Map:
return first.ValueMap() == second.ValueMap();
}
}
inline bool operator<(const PropertyValue &first, const PropertyValue &second) noexcept {
if (!PropertyValue::AreComparableTypes(first.type(), second.type())) return first.type() < second.type();
switch (first.type()) {
case PropertyValue::Type::Null:
return false;
case PropertyValue::Type::Bool:
return first.ValueBool() < second.ValueBool();
case PropertyValue::Type::Int:
if (second.type() == PropertyValue::Type::Double) {
return first.ValueInt() < second.ValueDouble();
} else {
return first.ValueInt() < second.ValueInt();
}
case PropertyValue::Type::Double:
if (second.type() == PropertyValue::Type::Double) {
return first.ValueDouble() < second.ValueDouble();
} else {
return first.ValueDouble() < second.ValueInt();
}
case PropertyValue::Type::String:
return first.ValueString() < second.ValueString();
case PropertyValue::Type::List:
return first.ValueList() < second.ValueList();
case PropertyValue::Type::Map:
return first.ValueMap() < second.ValueMap();
}
}
inline PropertyValue::PropertyValue(const PropertyValue &other) : type_(other.type_) {
switch (other.type_) {
case Type::Null:
return;
case Type::Bool:
this->bool_v = other.bool_v;
return;
case Type::Int:
this->int_v = other.int_v;
return;
case Type::Double:
this->double_v = other.double_v;
return;
case Type::String:
new (&string_v) std::string(other.string_v);
return;
case Type::List:
new (&list_v) std::vector<PropertyValue>(other.list_v);
return;
case Type::Map:
new (&map_v) std::map<std::string, PropertyValue>(other.map_v);
return;
}
}
inline PropertyValue::PropertyValue(PropertyValue &&other) noexcept : type_(other.type_) {
switch (other.type_) {
case Type::Null:
break;
case Type::Bool:
this->bool_v = other.bool_v;
break;
case Type::Int:
this->int_v = other.int_v;
break;
case Type::Double:
this->double_v = other.double_v;
break;
case Type::String:
new (&string_v) std::string(std::move(other.string_v));
break;
case Type::List:
new (&list_v) std::vector<PropertyValue>(std::move(other.list_v));
break;
case Type::Map:
new (&map_v) std::map<std::string, PropertyValue>(std::move(other.map_v));
break;
}
// reset the type of other
other.DestroyValue();
other.type_ = Type::Null;
}
inline PropertyValue &PropertyValue::operator=(const PropertyValue &other) {
if (this == &other) return *this;
DestroyValue();
type_ = other.type_;
switch (other.type_) {
case Type::Null:
break;
case Type::Bool:
this->bool_v = other.bool_v;
break;
case Type::Int:
this->int_v = other.int_v;
break;
case Type::Double:
this->double_v = other.double_v;
break;
case Type::String:
new (&string_v) std::string(other.string_v);
break;
case Type::List:
new (&list_v) std::vector<PropertyValue>(other.list_v);
break;
case Type::Map:
new (&map_v) std::map<std::string, PropertyValue>(other.map_v);
break;
}
return *this;
}
inline PropertyValue &PropertyValue::operator=(PropertyValue &&other) noexcept {
if (this == &other) return *this;
DestroyValue();
type_ = other.type_;
switch (other.type_) {
case Type::Null:
break;
case Type::Bool:
this->bool_v = other.bool_v;
break;
case Type::Int:
this->int_v = other.int_v;
break;
case Type::Double:
this->double_v = other.double_v;
break;
case Type::String:
new (&string_v) std::string(std::move(other.string_v));
break;
case Type::List:
new (&list_v) std::vector<PropertyValue>(std::move(other.list_v));
break;
case Type::Map:
new (&map_v) std::map<std::string, PropertyValue>(std::move(other.map_v));
break;
}
// reset the type of other
other.DestroyValue();
other.type_ = Type::Null;
return *this;
}
inline void PropertyValue::DestroyValue() noexcept {
switch (type_) {
// destructor for primitive types does nothing
case Type::Null:
case Type::Bool:
case Type::Int:
case Type::Double:
return;
// destructor for non primitive types since we used placement new
case Type::String:
// Clang fails to compile ~std::string. It seems it is a bug in some
// versions of clang. Using namespace std statement solves the issue.
using namespace std;
string_v.~string();
return;
case Type::List:
list_v.~vector();
return;
case Type::Map:
map_v.~map();
return;
}
}
} // namespace storage