OAR/Python: disable monitoring if oar modules cannot be imported properly

Signed-off-by: Nicola Vigano <nicola.vigano@esrf.fr>

zUtil_Python/dct_batch.py

@@ -12,7 +12,13 @@ import sys
 import dct_io_xml
 import dct_notification
 
-from oar import oar_utils
+try:
+    from oar import oar_utils
+    oar_available = True
+except ImportError as exc:
+    dct_io_xml.DCTOutput.printWarning(exc)
+    print("Turning of OAR services")
+    oar_available = False
 
 class DCTBatchConf(dct_io_xml.DCTXMLBase):
 
@@ -168,6 +174,9 @@ class DCTBatch(object):
         return functions
 
     def monitor_array(self, array, delay = 10, timeout = None):
+        if oar_available is not True:
+            raise EnvironmentError("OAR service is not available!")
+
         monitor = oar_utils.OARMonitorArray(array=array)
         result = monitor.monitor(delay=delay, timeout=timeout)
         if result is not None: