QHttpServerRouter Class

Provides functions to bind a URL to a ViewHandler. More...

Header: #include <QHttpServerRouter>
CMake: find_package(Qt6 REQUIRED COMPONENTS HttpServer)
target_link_libraries(mytarget PRIVATE Qt6::HttpServer)
qmake: QT += httpserver
Since: Qt 6.4

Public Functions

QHttpServerRouter()
~QHttpServerRouter()
bool addConverter(QAnyStringView regexp)
void addConverter(QMetaType metaType, QAnyStringView regexp)
bool addRule(std::unique_ptr<QHttpServerRouterRule> rule)
typename ViewTraits::BindableType bindCaptured(ViewHandler &&handler, const QRegularExpressionMatch &match) const
void clearConverters()
const QHash<QMetaType, QString> &converters() const
bool handleRequest(const QHttpServerRequest &request, QTcpSocket *socket) const
void removeConverter(QMetaType metaType)

Detailed Description

You can register ViewHandler as a callback for requests to a specific URL. Variable parts in the route can be specified by the arguments in ViewHandler.

Note: This is a low-level routing API for an HTTP server.

See the following example:

auto pageView = [] (const quint64 page) {
    qDebug() << "page" << page;
};
using ViewHandler = decltype(pageView);

QHttpServerRouter router;

// register callback pageView on request "/page/<number>"
// for example: "/page/10", "/page/15"
router.addRoute<ViewHandler>(
    new QHttpServerRouterRule("/page/", [=] (QRegularExpressionMatch &match,
                                             const QHttpServerRequest &,
                                             QTcpSocket *) {
    auto boundView = router.bindCaptured(pageView, match);

    // it calls pageView
    boundView();
}));

Member Function Documentation

QHttpServerRouter::QHttpServerRouter()

Creates a QHttpServerRouter object with default converters.

See also converters().

QHttpServerRouter::~QHttpServerRouter()

Destroys a QHttpServerRouter.

template <typename Type> bool QHttpServerRouter::addConverter(QAnyStringView regexp)

Adds a new converter for type Type matching regular expression regexp, and returns true if this was successful, otherwise returns false.

Automatically try to register an implicit converter from QString to Type. If there is already a converter of type Type, that converter's regexp is replaced with regexp.

struct CustomArg {
    int data = 10;

    CustomArg() {} ;
    CustomArg(const QString &urlArg) : data(urlArg.toInt()) {}
};
Q_DECLARE_METATYPE(CustomArg);

QHttpServerRouter router;
router.addConverter<CustomArg>(u"[+-]?\\d+"));

auto pageView = [] (const CustomArg &customArg) {
    qDebug("data: %d", customArg.data);
};
using ViewHandler = decltype(pageView);

auto rule = std::make_unique<QHttpServerRouterRule>(
    "/<arg>/<arg>/log",
    [&router, &pageView] (QRegularExpressionMatch &match,
                          const QHttpServerRequest &request,
                          QTcpSocket *socket) {
    // Bind and call viewHandler with match's captured string and quint32:
    router.bindCaptured(pageView, match)();
});

router.addRule<ViewHandler>(std::move(rule));

void QHttpServerRouter::addConverter(QMetaType metaType, QAnyStringView regexp)

Adds a new converter for type type matching regular expression regexp.

If there is already a converter of type type, that converter's regexp is replaced with regexp.

template <typename ViewHandler, typename ViewTraits> bool QHttpServerRouter::addRule(std::unique_ptr<QHttpServerRouterRule> rule)

Adds a new rule and returns true if this was successful.

Inside addRule, we determine ViewHandler arguments and generate a list of their QMetaType::Type ids. Then we parse the URL and replace each <arg> with a regexp for its type from the list.

QHttpServerRouter router;

using ViewHandler = decltype([] (const QString &page, const quint32 num) { });

auto rule = std::make_unique<QHttpServerRouterRule>(
    "/<arg>/<arg>/log",
    [] (QRegularExpressionMatch &match,
        const QHttpServerRequest &request,
        QTcpSocket *socket) {
});

router.addRule<ViewHandler>(std::move(rule));

template <typename ViewHandler, typename ViewTraits> typename ViewTraits::BindableType QHttpServerRouter::bindCaptured(ViewHandler &&handler, const QRegularExpressionMatch &match) const

Supplies the handler with arguments derived from a URL. Returns the bound function that accepts whatever remaining arguments the handler may take, supplying them to the handler after the URL-derived values. Each match of the regex applied to the URL (as a string) is converted to the type of the handler's parameter at its position, so that it can be passed as match.

QHttpServerRouter router;

auto pageView = [] (const QString &page, const quint32 num) {
    qDebug("page: %s, num: %d", qPrintable(page), num);
};
using ViewHandler = decltype(pageView);

auto rule = std::make_unique<QHttpServerRouterRule>(
    "/<arg>/<arg>/log",
    [&router, &pageView] (QRegularExpressionMatch &match,
                          const QHttpServerRequest &request,
                          QTcpSocket *socket) {
    // Bind and call viewHandler with match's captured string and quint32:
    router.bindCaptured(pageView, match)();
});

router.addRule<ViewHandler>(std::move(rule));

void QHttpServerRouter::clearConverters()

Removes all converters.

Note: clearConverters() does not set up default converters.

See also converters().

const QHash<QMetaType, QString> &QHttpServerRouter::converters() const

Returns a map of converter type and regexp.

The following converters are available by default:

ConstantDescription
QMetaType::Int 
QMetaType::Long 
QMetaType::LongLong 
QMetaType::Short 
QMetaType::UInt 
QMetaType::ULong 
QMetaType::ULongLong 
QMetaType::UShort 
QMetaType::Double 
QMetaType::Float 
QMetaType::QString 
QMetaType::QByteArray 
QMetaType::QUrl 
QMetaType::VoidAn empty converter.

bool QHttpServerRouter::handleRequest(const QHttpServerRequest &request, QTcpSocket *socket) const

Handles each new request for the HTTP server using socket.

Iterates through the list of rules to find the first that matches, then executes this rule, returning true. Returns false if no rule matches the request.

void QHttpServerRouter::removeConverter(QMetaType metaType)

Removes the converter for type type.

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