commit 1bde0c619b73979fa01171aaae85262db939e29d
Author: Aleix Pol <aleixpol@kde.org>
Date:   Tue Apr 9 23:26:44 2019 +0200

    Add debug information when a backend is being slow
    
    This can help us detect what's wrong whenever a backend gets stuck,
    which seems to happen every now and then.

diff --git a/libdiscover/resources/AbstractResourcesBackend.cpp b/libdiscover/resources/AbstractResourcesBackend.cpp
index e5d56e20..44dafc15 100644
--- a/libdiscover/resources/AbstractResourcesBackend.cpp
+++ b/libdiscover/resources/AbstractResourcesBackend.cpp
@@ -72,6 +72,18 @@ void ResultsStream::finish()
 AbstractResourcesBackend::AbstractResourcesBackend(QObject* parent)
     : QObject(parent)
 {
+    QTimer* fetchingChangedTimer = new QTimer(this);
+    fetchingChangedTimer->setInterval(3000);
+    fetchingChangedTimer->setSingleShot(true);
+    connect(fetchingChangedTimer, &QTimer::timeout, this, [this]{ qDebug() << "took really long to fetch" << this; });
+
+    connect(this, &AbstractResourcesBackend::fetchingChanged, this, [this, fetchingChangedTimer]{
+//         Q_ASSERT(isFetching() != fetchingChangedTimer->isActive());
+        if (isFetching())
+            fetchingChangedTimer->start();
+        else
+            fetchingChangedTimer->stop();
+    });
 }
 
 Transaction* AbstractResourcesBackend::installApplication(AbstractResource* app)