The qx-json header file provides various utilities for JSON data manipulation. More...

#include "qx/core/qx_core_export.h"
#include <QString>
#include <QJsonValueRef>
#include <QJsonObject>
#include <QJsonArray>
#include <QJsonDocument>
#include <QFile>
#include <QFileInfo>
#include "qx/core/qx-abstracterror.h"
#include "qx/core/qx-error.h"
#include "qx/utility/qx-macros.h"
#include "qx/utility/qx-concepts.h"

Include dependency graph for qx-json.h:

Classes
class	QxJson::Array
	The array class represents a JSON array node for use in error contexts. More...

class	QxJson::ArrayElement
	The array element key class represents a JSON Array element node for use in error contexts. More...

class	QxJson::Document
	The document class represents a JSON document node for use in error contexts. More...

class	QxJson::File
	The file class represents a JSON file node for use in error contexts. More...

class	Qx::JsonError
	The JsonError class is used to report errors related to JSON manipulation. More...

class	QxJson::Object
	The object class represents a JSON object node for use in error contexts. More...

class	QxJson::ObjectKey
	The object key class represents a JSON Object key node for use in error contexts. More...

class	Qx::QJsonParseErrorAdapter
	Allows QJsonParseError to be used via the Qx::Error interface. More...

Namespaces
namespace	Qx
	The `Qx` namespace is the main namespace through which all non-global functionality of the Qx library is accessed.

namespace	QxJson
	The `QxJson` namespace encapsulates the user-extensible implementation of Qx's JSON parsing facilities.

Concepts
concept	QxJson::qjson_type

concept	QxJson::json_struct_inside

concept	QxJson::json_struct_outside

concept	QxJson::json_struct

concept	QxJson::json_convertible

concept	QxJson::json_override_convertible

concept	QxJson::json_keyable

concept	QxJson::json_collective

concept	QxJson::json_associative

concept	QxJson::json_containing

concept	QxJson::json_optional

concept	Qx::json_root
	Specifies that a type is a valid analogue for a JSON document root element.

Macros
#define	QX_JSON_MEMBER(member) QxJsonPrivate::makeMemberMetadata<#member>(&StructT::member)

#define	QX_JSON_MEMBER_ALIASED(member, key) QxJsonPrivate::makeMemberMetadata<key>(&StructT::member)

#define	QX_JSON_MEMBER_OVERRIDE(Struct, member, ...)

#define	QX_JSON_STRUCT(...) __QX_JSON_META_STRUCT_INSIDE(std::make_tuple(QX_FOR_EACH_DELIM(QX_JSON_MEMBER, __VA_ARGS__)))

#define	QX_JSON_STRUCT_OUTSIDE(Struct, ...) __QX_JSON_META_STRUCT_OUTSIDE(Struct, std::make_tuple(QX_FOR_EACH_DELIM(QX_JSON_MEMBER, __VA_ARGS__)))

#define	QX_JSON_STRUCT_OUTSIDE_X(Struct, ...) __QX_JSON_META_STRUCT_OUTSIDE(Struct, std::make_tuple(__VA_ARGS__))

#define	QX_JSON_STRUCT_X(...) __QX_JSON_META_STRUCT_INSIDE(std::make_tuple(__VA_ARGS__))

Typedefs
using	QxJson::ContextNode = std::variant<File, Document, Object, ObjectKey, Array, ArrayElement>

Functions
QString	Qx::asString (const QJsonValue &value)

QList< QJsonValue >	Qx::findAllValues (const QJsonValue &rootValue, QStringView key)

template<typename Key , class Value >
Key	QxJson::keygen (const Value &value)=delete
	The keygen template function acts as an interface through which the derivation of a key for a given type when used in associative containers is defined.

template<typename T > requires QxJson::json_containing<T>
JsonError	Qx::parseJson (T &parsed, const QJsonArray &array)

template<typename T > requires json_root<T>
JsonError	Qx::parseJson (T &parsed, const QJsonDocument &doc)

template<typename T > requires QxJson::json_struct<T>
JsonError	Qx::parseJson (T &parsed, const QJsonObject &obj)

template<typename T > requires json_root<T>
JsonError	Qx::parseJson (T &parsed, const QString &filePath)

template<typename T > requires json_root<T>
JsonError	Qx::parseJson (T &parsed, QFile &file)

Detailed Description

The mechanisms of this file introduce a highly flexible, simple to use, declarative mechanism for parsing JSON data into user structs and other types.

For example, the following JSON data:

{
    "title": "Sample JSON Data",
    "info": {
        "rating": 10,
        "cool": true
    },
    "reviews": [
        "Wicked!",
        "Awesome!",
        "Fantastic!"
    ]
}

can easily be parsed into a corresponding set of C++ data structures like so:

#include <qx/core/qx-json.h>
 
struct Info
{
    int rating;
    bool cool;
    
    QX_JSON_STRUCT(rating, cool);
};
 
struct MyJson
{
    QString title;
    Info info;
    QList<QString> reviews;
    
    QX_JSON_STRUCT(title, info, reviews);
};
 
int main()
{
    QFile jsonFile("data.json");
    MyJson myJsonDoc;
 
    // Parse into custom structures
    Qx::JsonError je = Qx::parseJson(myJsonDoc, jsonFile);
    Q_ASSERT(!je.isValid());
}

See also: QX_JSON_STRUCT(), and QxJson.

Macro Definition Documentation

◆ QX_JSON_MEMBER

#define QX_JSON_MEMBER ( member ) QxJsonPrivate::makeMemberMetadata<#member>(&StructT::member)

Used to denote a JSON struct member whose name matches its key when using QX_JSON_STRUCT_X().

See also: QX_JSON_STRUCT_X()

◆ QX_JSON_MEMBER_ALIASED

#define QX_JSON_MEMBER_ALIASED	(		member,
			key ) QxJsonPrivate::makeMemberMetadata<key>(&StructT::member)

Used to denote a JSON struct member with a key that is different from its name when using QX_JSON_STRUCT_X().

key is to be a string literal.

See also: QX_JSON_STRUCT_X()

◆ QX_JSON_MEMBER_OVERRIDE

#define QX_JSON_MEMBER_OVERRIDE	(	Struct,
		member,
		... )

Value:

namespace QxJson \
{ \
    template<> \
    struct MemberOverrideCoverter<Struct, #member> \
    { \
        __VA_ARGS__\
    }; \
}

Used to define a member/key specific value parsing override for a JSON-tried struct. The specified member will be parsed using the provided function instead of a potentially available generic one for that type.

Must be used in namespace scope, outside of the struct definition.

struct MySpecialStruct
{
    int number;
    QString name;
    
    QX_JSON_STRUCT(number, name);     
}
 
QX_JSON_MEMBER_OVERRIDE(MySpecialStruct, name,
    static Qx::JsonError fromJson(QString& member, const QJsonValue& jv)
    {
        member = "OverridenName";
        return Qx::JsonError();
    }
)

◆ QX_JSON_STRUCT

#define QX_JSON_STRUCT ( ... ) __QX_JSON_META_STRUCT_INSIDE(std::make_tuple(QX_FOR_EACH_DELIM(QX_JSON_MEMBER, __VA_ARGS__)))

Specifies that a struct is a JSON-tied struct, which enables support for automatic parsing of a corresponding JSON object.

The name of each included member must match the name their corresponding JSON key.

struct MyStruct
{
    int number;
    QString name;
    
    QX_JSON_STRUCT(number, name);
}

See also: QX_JSON_STRUCT_OUTSIDE() and QX_JSON_STRUCT_X()

◆ QX_JSON_STRUCT_OUTSIDE

#define QX_JSON_STRUCT_OUTSIDE	(		Struct,
			... ) __QX_JSON_META_STRUCT_OUTSIDE(Struct, std::make_tuple(QX_FOR_EACH_DELIM(QX_JSON_MEMBER, __VA_ARGS__)))

Same as QX_JSON_STRUCT(), but is used outside of a struct instead of inside.

struct MyStruct
{
    int number;
    QString name;
}
 
// At global scope
QX_JSON_STRUCT_OUTSIDE(number, name);

This is useful for hiding the JSON parsing implementation details of a public struct within a different source file.

See also: QX_JSON_STRUCT()

◆ QX_JSON_STRUCT_OUTSIDE_X

#define QX_JSON_STRUCT_OUTSIDE_X	(		Struct,
			... ) __QX_JSON_META_STRUCT_OUTSIDE(Struct, std::make_tuple(__VA_ARGS__))

Same as QX_JSON_STRUCT_X(), but is used outside of a struct instead of inside.

See also: QX_JSON_STRUCT_OUTSIDE()

◆ QX_JSON_STRUCT_X

#define QX_JSON_STRUCT_X ( ... ) __QX_JSON_META_STRUCT_INSIDE(std::make_tuple(__VA_ARGS__))

Same as QX_JSON_STRUCT(), but allows for customization of member keys.

Each member must be wrapped in QX_JSON_MEMBER() or QX_JSON_MEMBER_ALIASED().

struct MyStruct
{
    int number;
    QString name;
    
    QX_JSON_STRUCT_X(
        QX_JSON_MEMBER(number),
        QX_JSON_MEMBER_ALIASED(name, "aliasName")
    );
}

Classes

Namespaces

Concepts

Macros

Typedefs

Functions