Added PCRE notification filtering/blocking

README.md

@@ -54,6 +54,50 @@ menu - Preferences - LXQt Settings - Desktop Notifications and is provided by th
 [Configuration Center](https://github.com/lxqt/lxqt-config#configuration-center)
 of [lxqt-config](https://github.com/lxqt/lxqt-config) as well.
 
+### Filtering
+It is possible to filter/suppress notifications with a [PCRE](https://www.pcre.org) by setting the
+`application_pcre_filter`, `body_pcre_filter`, or `summary_pcre_filter` in the
+`lxqt/notifications.conf`. These variables can be set with any valid PCRE with 
+each section being checked against its respective PCRE filter. If any of the
+PCREs are captured in the application, body, or summary then the message will 
+not be shown. The following example `lxqt/notifications.conf` any notification with the
+summary containing the words "hello", "goodbye", or "nope" will not be shown:
+```text
+[General]
+...
+application_pcre_filter=
+body_pcre_filter=
+summary_pcre_filter=(?:hello|goodbye|nope)
+...
+```
+https://regex101.com/r/nhtRtx/1
+
+#### Filtering Examples
+Filter/block all notifications from the applications: `noisy_app1`,
+`noisy_app2`, and `noisy_app3`.
+Add the following to lxqt/notification.conf:
+```text
+[General]
+...
+applicaiton_pcre_filter=(?:noisy_app1|noisy_app2|noisy_app3)
+body_pcre_filter=
+summary_pcre_filter=
+...
+```
+
+Filter/block all notifications containing the strings: `This is a test` and
+`This is another test`
+```text
+[General]
+...
+applicaiton_pcre_filter=
+body_pcre_filter=
+summary_pcre_filter=^(?=.*(?:This is a test|This is another test)).*$
+...
+```
+https://regex101.com/r/thW0qo/1
+
+
 ## Translations
 
 Translations can be done in [LXQt-Weblate](https://translate.lxqt-project.org/projects/lxqt-configuration/lxqt-notificationd)

src/notificationlayout.cpp

@@ -33,6 +33,7 @@
 #include <QBrush>
 #include <QSettings>
 #include <QStandardPaths>
+#include <QRegularExpression>
 
 NotificationLayout::NotificationLayout(QWidget *parent)
     : QWidget(parent),
@@ -71,16 +72,47 @@ void NotificationLayout::setSizes(int space, int width)
     }
 }
 
+void NotificationLayout::setPCREFilter(QRegularExpression& re, const QString& pattern) {
+    re.setPattern(pattern);
+    qWarning() << "Unable to compile regexp from pattern " << pattern << ", error: "
+        << re.errorString() << ", at position " << re.patternErrorOffset();
+}
+
+bool NotificationLayout::filter(const QString& input, const QRegularExpression& re) {
+    if (re.pattern().isEmpty() || !re.isValid())
+        return false;
+
+    return re.match(input).hasMatch();
+}
+
 void NotificationLayout::addNotification(uint id, const QString &application,
                                         const QString &summary, const QString &body,
                                         const QString &icon, int timeout,
                                         const QStringList& actions, const QVariantMap& hints,
                                         bool noSave)
 {
-//    qDebug() << "NotificationLayout::addNotification" << id << application << summary << body << icon << timeout;
+
+    bool applicationPCRECaptured = filter(application, m_application_pcre_filter);
+    bool bodyPCRECaptured = filter(summary, m_body_pcre_filter);
+    bool summaryPCRECaptured = filter(summary, m_summary_pcre_filter);
+    qInfo() << "New notification: ";
+    qInfo() << "  application: " << application;
+    qInfo() << "  application PCRE: " << m_application_pcre_filter;
+    qInfo() << "  application PCRE captured: " << QString::fromStdString( (applicationPCRECaptured ? "true" : "false"));
+    qInfo() << "  body: " << body;
+    qInfo() << "  body PCRE: " << m_body_pcre_filter;
+    qInfo() << "  body PCRE captured: " << QString::fromStdString( (bodyPCRECaptured ? "true" : "false"));
+    qInfo() << "  summary: " << summary;
+    qInfo() << "  summary PCRE: " << m_summary_pcre_filter;
+    qInfo() << "  summary PCRE captured: " << QString::fromStdString( (summaryPCRECaptured ? "true" : "false"));
+
     bool showNotification(!m_doNotDisturb
                           // always show our test notifications
                           || application == QL1S("lxqt-config-notificationd"));
+    showNotification = showNotification && !applicationPCRECaptured;
+    showNotification = showNotification && !bodyPCRECaptured;
+    showNotification = showNotification && !summaryPCRECaptured;
+    qInfo() << "  showNotification: " << QString::fromStdString( (showNotification ? "true" : "false"));
     if (m_notifications.contains(id))
     {
         // TODO/FIXME: it can be deleted by timer in this block. Locking?

src/notificationlayout.h

@@ -29,6 +29,7 @@
 #define NotificationLayout_H
 
 #include "notification.h"
+#include <QRegularExpression>
 
 
 class NotificationLayout : public QWidget
@@ -54,6 +55,20 @@ class NotificationLayout : public QWidget
         m_doNotDisturb = value;
     }
 
+    void setPCREFilter(QRegularExpression& re, const QString& pattern);
+
+    void setApplicationPCREFilter(const QString& pcre) {
+        setPCREFilter(m_application_pcre_filter, pcre);
+    }
+
+    void setBodyPCREFilter(const QString& pcre) {
+        setPCREFilter(m_body_pcre_filter, pcre);
+    }
+
+    void setSummaryPCREFilter(const QString& pcre) {
+        setPCREFilter(m_summary_pcre_filter, pcre);
+    }
+
     void setBlackList(const QStringList &l) {
         m_blackList = l;
     }
@@ -107,6 +122,9 @@ public slots:
     QVBoxLayout *m_layout;
     int m_unattendedMaxNum;
     bool m_doNotDisturb;
+    QRegularExpression m_application_pcre_filter;
+    QRegularExpression m_body_pcre_filter;
+    QRegularExpression m_summary_pcre_filter;
     QStringList m_blackList;
     QString m_cacheFile;
     QString m_cacheDateFormat;
@@ -117,6 +135,8 @@ public slots:
      */
     void checkHeight();
 
+    bool filter(const QString& input, const QRegularExpression& re);
+
 private slots:
     /*! \c Notification's timer timeouted, so closing the notifiaction
      */

src/notifyd.cpp

@@ -166,6 +166,9 @@ void Notifyd::reloadSettings()
             m_settings->value(QSL("screenWithMouse"),false).toBool(),
             m_doNotDisturb ? QStringList() : m_settings->value(QSL("blackList")).toStringList());
     m_area->layout()->setDoNotDisturb(m_doNotDisturb);
+    m_area->layout()->setApplicationPCREFilter(m_settings->value(QL1S("application_pcre_filter")).toString());
+    m_area->layout()->setBodyPCREFilter(m_settings->value(QL1S("body_pcre_filter")).toString());
+    m_area->layout()->setSummaryPCREFilter(m_settings->value(QL1S("summary_pcre_filter")).toString());
 
     if (m_trayIcon.isNull())
     {