Merge pull request #554 in ZP/z-push from...

Merge pull request #554 in ZP/z-push from bugfix/ZP-1247-unexpected-synckey-stateinvalidexception to develop

* commit '1d374d62':
  ZP-ZP-1247 Check for if a synckey was confirmed in the request.

src/lib/core/syncparameters.php

@@ -286,6 +286,17 @@ class SyncParameters extends StateObject {
         $this->checkCPO($this->currentCPO);
     }
 
+
+    /**
+     * Indicates if the confirmation status changed for the SyncKey.
+     *
+     * @access public
+     * @return boolean
+     */
+    public function HasConfirmationChanged() {
+        return $this->confirmationChanged;
+    }
+
     /**
      * Indicates if a exporter run is required. This is the case if the given folderstat is different from the saved one
      * or when the expiration time expired.

src/lib/request/sync.php

@@ -887,7 +887,7 @@ class Sync extends RequestProcessor {
 
             // Fir AS 14.0+ omit output for folder, if there were no incoming or outgoing changes and no Fetch
             if (Request::GetProtocolVersion() >= 14.0 && ! $spa->HasNewSyncKey() && $changecount == 0 && empty($actiondata["fetchids"]) && $status == SYNC_STATUS_SUCCESS &&
-                    ($newFolderStat === false || ! $spa->IsExporterRunRequired($newFolderStat))) {
+                    ! $spa->HasConfirmationChanged() && ($newFolderStat === false || ! $spa->IsExporterRunRequired($newFolderStat))) {
                 ZLog::Write(LOGLEVEL_DEBUG, sprintf("HandleSync: No changes found for %s folder id '%s'. Omitting output.", $spa->GetContentClass(), $spa->GetFolderId()));
                 continue;
             }
@@ -1208,12 +1208,14 @@ class Sync extends RequestProcessor {
                 self::$deviceManager->SetFolderSyncStatus($spa->GetFolderId(), DeviceManager::FLD_SYNC_COMPLETED);
 
                 // we should update the folderstat, but we recheck to see if it changed. If so, it's not updated to force another sync
-                $newFolderStatAfterExport = self::$backend->GetFolderStat(ZPush::GetAdditionalSyncFolderStore($spa->GetBackendFolderId()), $spa->GetBackendFolderId());
-                if ($newFolderStat === $newFolderStatAfterExport) {
-                    $this->setFolderStat($spa, $newFolderStat);
-                }
-                else {
-                    ZLog::Write(LOGLEVEL_DEBUG, "Sync() Folderstat differs after export, force another exporter run.");
+                if (self::$backend->HasFolderStats()) {
+                    $newFolderStatAfterExport = self::$backend->GetFolderStat(ZPush::GetAdditionalSyncFolderStore($spa->GetBackendFolderId()), $spa->GetBackendFolderId());
+                    if ($newFolderStat === $newFolderStatAfterExport) {
+                        $this->setFolderStat($spa, $newFolderStat);
+                    }
+                    else {
+                        ZLog::Write(LOGLEVEL_DEBUG, "Sync() Folderstat differs after export, force another exporter run.");
+                    }
                 }
             }
             else