refs #494 Use QFileSystemWatcher to watch for remote changes to the data store.

src/blackcore/datacache.cpp

@@ -27,9 +27,10 @@ namespace BlackCore
         }
 
         connect(this, &CValueCache::valuesChangedByLocal, this, &CDataCache::saveToStore);
+        connect(&m_watcher, &QFileSystemWatcher::fileChanged, this, [this] { loadFromStore(); });
 
-        connect(&m_reloadTimer, &QTimer::timeout, this, [this]() { loadFromStore(); });
-        m_reloadTimer.start(1000);
+        if (! QFile::exists(m_revisionFileName)) { QFile(m_revisionFileName).open(QFile::WriteOnly); }
+        m_watcher.addPath(m_revisionFileName);
         loadFromStore();
     }
 

src/blackcore/datacache.h

@@ -15,7 +15,7 @@
 #include "blackcore/blackcoreexport.h"
 #include "blackmisc/valuecache.h"
 #include <QUuid>
-#include <QTimer>
+#include <QFileSystemWatcher>
 
 namespace BlackCore
 {
@@ -46,7 +46,7 @@ namespace BlackCore
         //! \param defer Whether to defer applying the changes. Used when called by saveToStore.
         void loadFromStore(bool lock = true, bool defer = false);
 
-        QTimer m_reloadTimer;
+        QFileSystemWatcher m_watcher;
         QUuid m_revision;
         const QString m_revisionFileName { persistentStore() + "/.rev" };
         BlackMisc::CVariantMap m_deferredChanges;