// Copyright (C) 2019 The Qt Company Ltd. // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only #include #include #include #include #include #include #include #include #include QT_BEGIN_NAMESPACE Q_STATIC_LOGGING_CATEGORY(lcRouterRule, "qt.httpserver.router.rule") /*! \class QHttpServerRouterRule \since 6.4 \brief The QHttpServerRouterRule is the base class for QHttpServerRouter rules. \inmodule QtHttpServer QHttpServerRouterRule defines the relationship between a request path, an HTTP method, and the corresponding handler callback. A QHttpServerRouter is a collection of these rules, executing the appropriate handler when a request matches both the path and method. The handler is responsible for generating the response. \section1 Paths and Patterns Each QHttpServerRouterRule includes a path or pattern that determines which requests it can handle. Paths may contain placeholders that are passed to the handler. The examples below illustrate path patterns using the QHttpServer::route() convenience method, though they can also be set using the QHttpServerRouterRule constructor. In the simplest case the path is a string with a leading \c "/": \code QHttpServer server; server.route("/user", [] () { return "hello user"; } ); \endcode This path pattern defines a rule that directs all requests to \c "/user" to the specified handler, which in this case is a simple lambda function. (Note that when using QHttpServerRouterRule directly, the handler syntax differs—see below.) A trailing \c "/" in the path pattern allows the rule to match additional paths with arguments after the \c "/". When using the QHttpServer::route() convenience method, the argument is automatically passed to the lambda function: \code server.route("/user/", [] ( qint64 id ) { return "hello user"; } ); \endcode This would match request paths such as \c "/user/1", \c "/user/2", and so on. \section2 Capturing Arguments in the Path You can place arguments anywhere in the path pattern using the \c "" placeholders, and multiple of them are supported in the path: \code server.route("/user//history", [] (qint64 id){ return "hello user"; } ); server.route("/user//history/", [] (qint64 id, qint64 page){ return "hello user"; } ); \endcode For example, this would match a request like \c "/user/1/history/2". Any data type registered in QHttpServerRouter::converters() can be used in both the callback function and the corresponding placeholders in the path. \section1 Request Method The request method corresponds to one of the values in QHttpServerRequest::Method. If no method is specified when constructing a rule, it will match requests of any known method. \section1 Handler Signature A handler is a callback function with the following signature: \code void (*)(const QRegularExpressionMatch &, const QHttpServerRequest &, QHttpServerResponder &); \endcode \list \li The first argument receives any matched capture groups from the path. \li The second argument contains request details. \li The third argument is used to send the response. \endlist \section1 Adding Rules to QHttpServerRouter The example below demonstrates how to create and register a new rule with a handler in \l QHttpServerRouter: \code template void route(const char *path, const QHttpServerRequest::Methods methods, ViewHandler &&viewHandler) { auto rule = std::make_unique( path, methods, [this, viewHandler = std::forward(viewHandler)] (QRegularExpressionMatch &match, const QHttpServerRequest &request, QHttpServerResponder &responder) mutable { auto boundViewHandler = QHttpServerRouterRule::bindCaptured( this, std::move(viewHandler), match); boundViewHandler(); // Execute the handler }); // Add rule to the router router.addRule(std::move(rule)); } // Valid: route("/user/", [] (qint64 id) { } ); // Matches "/user/1", "/user/3", etc. route("/user//history", [] (qint64 id) { } ); // Matches "/user/1/history", "/user/2/history" route("/user//history/", [] (qint64 id, qint64 page) { } ); // Matches "/user/1/history/1", "/user/2/history/2" \endcode \note This is a low-level API. For higher-level alternatives, see \l QHttpServer. \note Regular expressions are not supported in path patterns, but you can use \l QHttpServerRouter::addConverter() to match \c "" to a specific type. */ /*! \fn template > static typename ViewTraits::BindableType QHttpServerRouterRule::bindCaptured(QObject *receiver, Functor &&slot, const QRegularExpressionMatch &match) const Binds the given \a receiver and \a slot with arguments extracted from the URL. The function returns a bound callable that takes any remaining arguments required by the handler, supplying them to \a slot after the URL-derived values. Each captured value from the URL (as a string) is converted to the corresponding parameter type in the handler based on its position, ensuring it can be passed as \a match. \code 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( "///log", [&router, &pageView] (QRegularExpressionMatch &match, const QHttpServerRequest &request, QHttpServerResponder &&responder) { // Bind and call viewHandler with match's captured string and quint32: QHttpServerRouterRule::bindCaptured(pageView, match)(); }); router.addRule(std::move(rule)); \endcode */ /*! \fn template QHttpServerRouterRule::QHttpServerRouterRule(const QString &pathPattern, const QHttpServerRequest::Methods methods, const QObject *receiver, Functor &&slot) Creates a routing rule for \a pathPattern and \a methods, connecting it to the specified \a receiver and \a slot. \list \li The \a slot can be a function pointer, non-mutable lambda, or any other copyable callable with \c const call operator. \li If \a slot is callable, \a receiver acts as its context object. \li The handler remains valid until the \a receiver is destroyed. \endlist The rule can handle any combination of available HTTP methods. \sa QHttpServerRequest::Methods */ /*! \fn template QHttpServerRouterRule::QHttpServerRouterRule(const QString &pathPattern, const QObject *receiver, Functor &&slot) \overload This overload constructs a routing rule for \a pathPattern and associates it with \a receiver and \a slot. \list \li It defaults to \l QHttpServerRequest::Method::AnyKnown, meaning it will match any recognized HTTP method. \li The \a slot can be a function pointer, non-mutable lambda, or any other copyable callable with \c const call operator. \li If \a slot is callable, \a receiver acts as its context object. \li The handler remains valid until the \a receiver is destroyed. \endlist */ QHttpServerRouterRule::QHttpServerRouterRule(const QString &pathPattern, const QHttpServerRequest::Methods methods, const QObject *context, QtPrivate::QSlotObjectBase *slotObjRaw) : QHttpServerRouterRule(new QHttpServerRouterRulePrivate{ pathPattern, methods, QtPrivate::SlotObjUniquePtr(slotObjRaw), QPointer(context), {}}) { Q_ASSERT(slotObjRaw); } /*! \internal */ QHttpServerRouterRule::QHttpServerRouterRule(QHttpServerRouterRulePrivate *d) : d_ptr(d) { } /*! Destroys a QHttpServerRouterRule. */ QHttpServerRouterRule::~QHttpServerRouterRule() { } /*! Retrieves the context object associated with this rule. This object serves as the receiver responsible for handling the request. */ const QObject *QHttpServerRouterRule::contextObject() const { Q_D(const QHttpServerRouterRule); return d->context; } /*! Validates the Request Method. Returns \c true if the specified HTTP method is valid. */ bool QHttpServerRouterRule::hasValidMethods() const { Q_D(const QHttpServerRouterRule); return d->methods & QHttpServerRequest::Method::AnyKnown; } /*! Executes the rule. Processes the given \a request by checking if it matches this rule. \list \li This function is called by QHttpServerRouter when a new \a request is received. \li If the \a request matches the rule, it handles the request by sending a response through the provided \a responder and returns \c true. \li If there is no match, it returns \c false. \endlist */ bool QHttpServerRouterRule::exec(const QHttpServerRequest &request, QHttpServerResponder &responder) const { Q_D(const QHttpServerRouterRule); if (!d->routerHandler) return false; QRegularExpressionMatch match; if (!matches(request, &match)) return false; void *args[] = { nullptr, &match, const_cast(&request), &responder }; Q_ASSERT(d->routerHandler); d->routerHandler->call(nullptr, args); return true; } /*! Determines whether the provided \a request meets the conditions of this rule. \list \li This virtual function is called by \l exec() to evaluate the \a request. \li If the request matches, the details are stored in \a match (which \e{must not} be \c nullptr), and the function returns \c true. \li Otherwise, it returns \c false. \endlist */ bool QHttpServerRouterRule::matches(const QHttpServerRequest &request, QRegularExpressionMatch *match) const { Q_D(const QHttpServerRouterRule); if (d->methods && !(d->methods & request.method())) return false; *match = d->pathRegexp.match(request.url().path()); return (match->hasMatch() && d->pathRegexp.captureCount() == match->lastCapturedIndex()); } /*! \internal */ bool QHttpServerRouterRule::createPathRegexp(std::initializer_list metaTypes, const QHash &converters) { Q_D(QHttpServerRouterRule); QString pathRegexp = d->pathPattern; const QLatin1StringView arg(""); for (auto metaType : metaTypes) { if (metaType.id() >= QMetaType::User && !QMetaType::hasRegisteredConverterFunction(QMetaType::fromType(), metaType)) { qCWarning(lcRouterRule, "%s has not registered a converter to QString. " "Use QHttpServerRouter::addConveter(converter).", metaType.name()); return false; } auto it = converters.constFind(metaType); if (it == converters.end()) { qCWarning(lcRouterRule, "Can not find converter for type: %s", metaType.name()); return false; } if (it->isEmpty()) continue; const auto index = pathRegexp.indexOf(arg); const QString ®exp = QLatin1Char('(') % *it % QLatin1Char(')'); if (index == -1) pathRegexp.append(regexp); else pathRegexp.replace(index, arg.size(), regexp); } if (pathRegexp.indexOf(arg) != -1) { qCWarning(lcRouterRule) << "not enough types or one of the types is not supported, regexp:" << pathRegexp << ", pattern:" << d->pathPattern << ", types:" << metaTypes; return false; } if (!pathRegexp.startsWith(QLatin1Char('^'))) pathRegexp = QLatin1Char('^') % pathRegexp; if (!pathRegexp.endsWith(QLatin1Char('$'))) pathRegexp += u'$'; qCDebug(lcRouterRule) << "url pathRegexp:" << pathRegexp; d->pathRegexp.setPattern(pathRegexp); d->pathRegexp.optimize(); return true; } QT_END_NAMESPACE