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// Copyright (C) 2019 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
// Qt-Security score:significant reason:default
#include <QtHttpServer/qhttpserverrouterrule.h>
#include <QtHttpServer/qhttpserverresponder.h>
#include <private/qhttpserverrouterrule_p.h>
#include <private/qhttpserverrequest_p.h>
#include <QtCore/qhash.h>
#include <QtCore/qmetaobject.h>
#include <QtCore/qloggingcategory.h>
#include <QtCore/qregularexpression.h>
#include <QtCore/qstringbuilder.h>
#include <QtCore/qdebug.h>
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 "<arg>"
placeholders, and multiple of them are supported in the path:
\code
server.route("/user/<arg>/history", [] (qint64 id){ return "hello user"; } );
server.route("/user/<arg>/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<typename ViewHandler>
void route(const char *path, const QHttpServerRequest::Methods methods, ViewHandler &&viewHandler)
{
auto rule = std::make_unique<QHttpServerRouterRule>(
path, methods, [this, viewHandler = std::forward<ViewHandler>(viewHandler)]
(QRegularExpressionMatch &match,
const QHttpServerRequest &request,
QHttpServerResponder &responder) mutable {
auto boundViewHandler = QHttpServerRouterRule::bindCaptured<ViewHandler>(
this, std::move(viewHandler), match);
boundViewHandler(); // Execute the handler
});
// Add rule to the router
router.addRule<ViewHandler>(std::move(rule));
}
// Valid:
route("/user/", [] (qint64 id) { } ); // Matches "/user/1", "/user/3", etc.
route("/user/<arg>/history", [] (qint64 id) { } ); // Matches "/user/1/history", "/user/2/history"
route("/user/<arg>/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 "<arg>" to a
specific type.
*/
/*! \fn template <typename Functor, typename ViewTraits = QHttpServerRouterViewTraits<Functor>> 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<QHttpServerRouterRule>(
"/<arg>/<arg>/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<ViewHandler>(std::move(rule));
\endcode
*/
/*! \fn template <typename Functor> 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 <typename Functor> 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<QHttpServerRequest *>(&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<QMetaType> metaTypes,
const QHash<QMetaType, QString> &converters)
{
Q_D(QHttpServerRouterRule);
QString pathRegexp = d->pathPattern;
const QLatin1StringView arg("<arg>");
for (auto metaType : metaTypes) {
if (metaType.id() >= QMetaType::User
&& !QMetaType::hasRegisteredConverterFunction(QMetaType::fromType<QString>(), metaType)) {
qCWarning(lcRouterRule,
"%s has not registered a converter to QString. "
"Use QHttpServerRouter::addConveter<Type>(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