Only build with offline updats if it's available

libdiscover/backends/PackageKitBackend/CMakeLists.txt

@@ -14,6 +14,11 @@ add_library(packagekit-backend MODULE PackageKitBackend.cpp
     LocalFilePKResource.cpp
     TransactionSet.cpp
 )
+
+if(packagekitqt5_VERSION VERSION_GREATER 0.9.7)
+    target_compile_definitions(packagekit-backend -DHAS_OFFLINE_UPDATES)
+endif()
+
 target_link_libraries(packagekit-backend PRIVATE Discover::Common Qt5::Core PK::packagekitqt5 KF5::ConfigGui KF5::KIOCore KF5::Archive AppStreamQt)
 
 install(TARGETS packagekit-backend DESTINATION ${PLUGIN_INSTALL_DIR}/discover)

libdiscover/backends/PackageKitBackend/PackageKitUpdater.cpp

@@ -140,10 +140,12 @@ void PackageKitUpdater::processProceedFunction()
 
 void PackageKitUpdater::proceed()
 {
-    if (!m_proceedFunctions.isEmpty()) {
+    if (!m_proceedFunctions.isEmpty())
         processProceedFunction();
-    } else if (qEnvironmentVariableIsSet("PK_OFFLINE_UPDATE"))
+#ifdef HAS_OFFLINE_UPDATES
+    else if (qEnvironmentVariableIsSet("PK_OFFLINE_UPDATE"))
         setupTransaction(PackageKit::Transaction::TransactionFlagOnlyTrusted | PackageKit::Transaction::TransactionFlagOnlyDownload);
+#endif
     else
         setupTransaction(PackageKit::Transaction::TransactionFlagOnlyTrusted);
 }
@@ -181,7 +183,11 @@ void PackageKitUpdater::finished(PackageKit::Transaction::Exit exit, uint /*time
     fetchLastUpdateTime();
 
     if (qEnvironmentVariableIsSet("PK_OFFLINE_UPDATE"))
+#ifdef HAS_OFFLINE_UPDATES
         PackageKit::Daemon::global()->offlineTrigger(PackageKit::Daemon::ActionReboot);
+#else
+        qWarning() << "PK_OFFLINE_UPDATE is set but discover was built against an old version of PackageKitQt that didn't support offline updates";
+#endif
 }
 
 void PackageKitUpdater::cancellableChanged()