sdrangel/httpserver/httpsession.h

125 wiersze
3.0 KiB
C++

/**
@file
@author Stefan Frings
*/
#ifndef HTTPSESSION_H
#define HTTPSESSION_H
#include <QByteArray>
#include <QVariant>
#include <QReadWriteLock>
#include "httpglobal.h"
#include "export.h"
namespace qtwebapp {
/**
This class stores data for a single HTTP session.
A session can store any number of key/value pairs. This class uses implicit
sharing for read and write access. This class is thread safe.
@see HttpSessionStore should be used to create and get instances of this class.
*/
class HTTPSERVER_API HttpSession {
public:
/**
Constructor.
@param canStore The session can store data, if this parameter is true.
Otherwise all calls to set() and remove() do not have any effect.
*/
HttpSession(bool canStore=false);
/**
Copy constructor. Creates another HttpSession object that shares the
data of the other object.
*/
HttpSession(const HttpSession& other);
/**
Copy operator. Detaches from the current shared data and attaches to
the data of the other object.
*/
HttpSession& operator= (const HttpSession& other);
/**
Destructor. Detaches from the shared data.
*/
virtual ~HttpSession();
/** Get the unique ID of this session. This method is thread safe. */
QByteArray getId() const;
/**
Null sessions cannot store data. All calls to set() and remove()
do not have any effect.This method is thread safe.
*/
bool isNull() const;
/** Set a value. This method is thread safe. */
void set(const QByteArray& key, const QVariant& value);
/** Remove a value. This method is thread safe. */
void remove(const QByteArray& key);
/** Get a value. This method is thread safe. */
QVariant get(const QByteArray& key) const;
/** Check if a key exists. This method is thread safe. */
bool contains(const QByteArray& key) const;
/**
Get a copy of all data stored in this session.
Changes to the session do not affect the copy and vice versa.
This method is thread safe.
*/
QMap<QByteArray,QVariant> getAll() const;
/**
Get the timestamp of last access. That is the time when the last
HttpSessionStore::getSession() has been called.
This method is thread safe.
*/
qint64 getLastAccess() const;
/**
Set the timestamp of last access, to renew the timeout period.
Called by HttpSessionStore::getSession().
This method is thread safe.
*/
void setLastAccess();
private:
struct HttpSessionData {
/** Unique ID */
QByteArray id;
/** Timestamp of last access, set by the HttpSessionStore */
qint64 lastAccess;
/** Reference counter */
int refCount;
/** Used to synchronize threads */
QReadWriteLock lock;
/** Storage for the key/value pairs; */
QMap<QByteArray,QVariant> values;
};
/** Pointer to the shared data. */
HttpSessionData* dataPtr;
};
} // end of namespace
#endif // HTTPSESSION_H