Add support for session inactivity timeouts

8 files changed, 83 insertions, 12 deletions

diff --git a/src/eventqueue.cpp b/src/eventqueue.cpp
index bb4bc41..aeba7d4 100644
--- a/src/eventqueue.cpp
+++ b/src/eventqueue.cpp
@@ -346,7 +346,7 @@ json_object *EventQueue::jsonTextUpdateEvent(const EventEntry &event) const
 
 json_object *EventQueue::toJsonWidgetType(QWidget *widget) const
 {
-    if (!widget || m_session->m_server->shouldSkipUpdate(widget->metaObject()->className()))
+    if (!widget || m_session && m_session->m_server->shouldSkipUpdate(widget->metaObject()->className()))
         return json_object_new_string("skippedwidget");
     if (qobject_cast<QLineEdit *>(widget))
         return json_object_new_string("lineedit");
diff --git a/src/eventqueue.h b/src/eventqueue.h
index 7d93e1b..13dc055 100644
--- a/src/eventqueue.h
+++ b/src/eventqueue.h
@@ -55,7 +55,7 @@ public:
     bool isEmpty() { return events.isEmpty(); }
     static QByteArray pngCompress(const QImage &image);
     //private:
-    Session *m_session; 
+    QPointer<Session> m_session;
     QQueue<EventEntry> events;
     QHash<quintptr, QImage> images;
     QHash<quintptr, QByteArray> compressedImages;
diff --git a/src/sessionserver.cpp b/src/sessionserver.cpp
index 37ff160..77a189f 100644
--- a/src/sessionserver.cpp
+++ b/src/sessionserver.cpp
@@ -5,7 +5,6 @@
 
 #include <json.h>
 
-
 QWidget *sharedRoot = 0;
 
 SessionServer::SessionServer(QWidget *widget, Session *session, Server *server)
@@ -14,8 +13,11 @@ SessionServer::SessionServer(QWidget *widget, Session *session, Server *server)
         sharedRoot = new QWidget();
         sharedRoot->resize(1000, 1000);
         sharedRoot->setAttribute(Qt::WA_DontShowOnScreen);
+        sharedRoot->setAttribute(Qt::WA_ForceUpdatesDisabled);
+        sharedRoot->setAttribute(Qt::WA_OpaquePaintEvent);
         sharedRoot->show();
     }
+
     widget->setParent(sharedRoot);
     widget->move(0,0);
     rootWidget = widget;
@@ -23,6 +25,7 @@ SessionServer::SessionServer(QWidget *widget, Session *session, Server *server)
     widgetEventHandler = new WidgetEventHandler(widget, server);
         
     rootWidget->setAttribute(Qt::WA_DontShowOnScreen);
+    rootWidget->setAttribute(Qt::WA_OpaquePaintEvent);
 
     // try to avoid creating the backingstore
     rootWidget->setAttribute(Qt::WA_PaintOnScreen);
diff --git a/src/webclient.cpp b/src/webclient.cpp
index 2777e4f..8a507d8 100644
--- a/src/webclient.cpp
+++ b/src/webclient.cpp
@@ -44,6 +44,11 @@ void WebClient::setActiveSessionLimitHtml(const QString &html)
     this->server->activeSessionLimitHtml = html.toUtf8();
 }
 
+void WebClient::setInactiveSessionTimeout(int seconds)
+{
+    this->server->inactiveSessionTimeout = seconds;
+}
+
 void WebClient::newSession_internal(Session *session)
 {
     QWidget *rootWidget = 0;
diff --git a/src/webclient.h b/src/webclient.h
index ccbd6c5..5779a65 100644
--- a/src/webclient.h
+++ b/src/webclient.h
@@ -23,6 +23,7 @@ public:
 
     void setActiveSessionLimit(int sessionLimit);
     void setActiveSessionLimitHtml(const QString &html);
+    void setInactiveSessionTimeout(int seconds);
 
     enum WidgetHint { StaticWidget, NoDisplayWidget };
     void setWidgetHint(QWidget *widget, WidgetHint hint);
diff --git a/src/webclientserver.cpp b/src/webclientserver.cpp
index f29abf0..762664b 100644
--- a/src/webclientserver.cpp
+++ b/src/webclientserver.cpp
@@ -49,11 +49,11 @@ void HttpRequest::parseText()
        if (line.startsWith("GET")) {
              m_path = QUrl::fromPercentEncoding(line.mid(4).split(' ').at(0)).toAscii(); // ### assumes well-formed string
        } else if (line.startsWith("POST")) {
-             m_path = QUrl::fromPercentEncoding(line.mid(5).split(' ').at(0)).toAscii(); // ### assumes well-formed string
+              m_path = QUrl::fromPercentEncoding(line.mid(5).split(' ').at(0)).toAscii(); // ### assumes well-formed string
        } else if (line.startsWith("Cookie:")) {
-//            qDebug() << "cookie line" << line.simplified();
+//            DEBUG << "cookie line" << line.simplified();
             m_cookies = line.mid(7).simplified(); // remove "Cookie:"
-//            qDebug() << "cookies text" << m_cookies;
+//            DEBUG << "cookies text" << m_cookies;
             foreach (const QByteArray cookieText, m_cookies.split(';')){
                 if (cookieText.contains('=')) {
                     QList<QByteArray> cookieParts = cookieText.split('=');
@@ -159,7 +159,7 @@ QByteArray HttpResponse::toText()
 Session::Session(Server *server, int sessionId)
 :m_sessionId(sessionId), m_idleSocket(0), m_server(server)
 {
-
+    lastActivityTime = QDateTime::currentDateTime();
 }
 
 int Session::sessionId()
@@ -198,7 +198,7 @@ Server::Server(quint16 port)
     this->port = port;
     connect(this, SIGNAL(newConnection()), SLOT(connectionAvailable()));
     listen(QHostAddress::Any, port);
-    qDebug() << QString("Server running on: http://" + QHostInfo::localHostName() + ":" + QString::number(port) + "/");
+    DEBUG << QString("Server running on: http://" + QHostInfo::localHostName() + ":" + QString::number(port) + "/");
     qsrand(QDateTime::currentDateTime().toTime_t());
     nextCookieId = qrand();
     dynamicBytesWritten = 0;
@@ -208,7 +208,10 @@ Server::Server(quint16 port)
     totalSessions = 0;
     activeSessionLimit = INT_MAX;
     activeSessionLimitHtml = "<html><body>Active session limit exceeded.</body></html>";
+    inactiveSessionTimeout = 60 * 10;
 
+    connect(&purgeInactiveSessionsTimer, SIGNAL(timeout()), SLOT(purgeInactiveSessions()));
+    purgeInactiveSessionsTimer.start(1000 / 1);
 // This didn't work out. Disable for now.
     sendUpdatesForPlainQWidgets = true;
 //    skipUpdatesClasses.insert("QWidget");
@@ -293,7 +296,7 @@ void Server::dataOnSocket()
 
     if (session == 0) { 
         // ### accept unknown sessions for now, TODO do authentication here.
-        DEBUG << "new session for" << sessionId;
+        DEBUG << "create new session";
         
         if (totalSessions >= activeSessionLimit) {
             dynamicBytesWritten += activeSessionLimitHtml.size();
@@ -320,6 +323,8 @@ void Server::dataOnSocket()
  //       DEBUG << "found session for" << sessionId;
     }
 
+    session->lastActivityTime = QDateTime::currentDateTime();
+
     // Strip away the page ids: "-pageId="
 /*
     int index = request.m_path.indexOf("-pageId=");
@@ -372,12 +377,62 @@ void Server::dataOnSocket()
 //    DEBUG << "socket write response done";
 }
 
+void Server::purgeInactiveSessions()
+{
+    DEBUG << "purgeInactiveSessions";
+    QDateTime now = QDateTime::currentDateTime();
+
+    // find where we left off the last time, restart from
+    // the beginning if not found.
+    QHash<int, Session *>::iterator it = activeSessions.find(lastSessionVisited);
+    if (it == activeSessions.end())
+        it = activeSessions.begin();
+
+    const int maxSessonsToExamine = 50; // avoid pausing to long.
+    int i = 0;
+    while (it != activeSessions.end()) {
+        if (i > maxSessonsToExamine) {
+            lastSessionVisited = it.key();
+            return;
+        }
+
+        Session *session = it.value();
+        DEBUG << "last act" <<  session << session->lastActivityTime;
+        int inactiveSeconds = now.toTime_t() - session->lastActivityTime.toTime_t();
+        DEBUG << "inactive" << inactiveSeconds;
+        if (inactiveSeconds > inactiveSessionTimeout) {
+            QHash<int, Session *>::iterator itToDelete = it;
+
+            // get the next key so the search can continue after the
+            // erase. (all iterators are invalidated.)
+            ++it;
+            if (it == activeSessions.end()) {
+                delete itToDelete.value();
+                activeSessions.erase(itToDelete);
+                it = activeSessions.end();
+            } else {
+                int newKey = it.key();
+                delete itToDelete.value();
+                activeSessions.erase(itToDelete);
+                it = activeSessions.find(newKey);
+            }
+            continue; // it has been repositioned. (i has not been incremented -
+                      // there is no limit to how many session we can delete in one go.)
+        }
+        ++it;
+        ++i;
+    }
+
+    // reached the end, restart for next time.
+    lastSessionVisited = -1; //actually a valid session value, but most likely a miss.
+}
+
 QByteArray Server::createStatiticsPage()
 {
     const double ec2DataRate=0.02 / (1000 * 1000 * 1000) ; // cost per byte
     const double ec2InstanceRate = 0.1; // cost per hour
     const double upHours = (QDateTime::currentDateTime().toTime_t() - serverStart.toTime_t() / (60.0 * 60.0));
-    qDebug() << "up" << upHours << QDateTime::currentDateTime().toTime_t();
+    DEBUG << "up" << upHours << QDateTime::currentDateTime().toTime_t();
     QByteArray stats;
     stats += "<b> Statistics </b><br><br>";
     stats += "<table border=1>";
diff --git a/src/webclientserver.h b/src/webclientserver.h
index 032b101..4c45f31 100644
--- a/src/webclientserver.h
+++ b/src/webclientserver.h
@@ -74,7 +74,7 @@ public:
     HttpRequest m_idleRequest;
     HttpResponse m_idleResponse;
     Server *m_server;
-
+    QDateTime lastActivityTime;
 };
 
 class FileServer : public QObject
@@ -107,9 +107,13 @@ public slots:
 private slots:
     void connectionAvailable();
     void dataOnSocket();
+private slots:
+    void purgeInactiveSessions();
 private:
     void printRequest(const QList<QByteArray> &request);
     QHash<int, Session *> activeSessions;
+    QTimer purgeInactiveSessionsTimer; // kills inactive sessions
+    int lastSessionVisited;
     int nextCookieId;
     quint16 port;
     FileServer fileServer;
@@ -125,6 +129,7 @@ private:
 public:
     int activeSessionLimit;
     QByteArray activeSessionLimitHtml;
+    int inactiveSessionTimeout;
     bool sendUpdatesForPlainQWidgets;
     bool shouldSkipUpdate(const QByteArray &className);
     QSet<QByteArray> skipUpdatesClasses;
diff --git a/src/widgeteventhandler.cpp b/src/widgeteventhandler.cpp
index 3568c43..b77dc6c 100644
--- a/src/widgeteventhandler.cpp
+++ b/src/widgeteventhandler.cpp
@@ -108,7 +108,9 @@ void WidgetEventHandler::addPendingUpdate(QWidget* widget, const QRect &rect)
 bool WidgetEventHandler::eventFilter(QObject *object, QEvent *event)
 {
     QWidget *widget = qobject_cast<QWidget *>(object);
-
+    extern QWidget *sharedRoot;
+    if (widget == sharedRoot)
+        return true;
     if (event->type() == QEvent::Paint) {
         if (server->shouldSkipUpdate(widget->metaObject()->className())) {
            // qDebug() << "skip plain widget" << widget;