caching_backend: increased verbosity of error message when adding values to closed sections

and extended to the routines handling arrays

common/python/nomadcore/caching_backend.py

@@ -144,21 +144,27 @@ class CachingSectionManager(object):
         try:
             self.openSections[gI].addValue(valueMetaInfo, value)
         except:
-            raise Exception("Cannot add value to section %d (%d) of %s, as it is not open" % (gI, gIndex, self.metaInfo.name))
+            raise Exception("Cannot add value for metadata %s to section %d (%d) of %s, as it is not open" % (valueMetaInfo.name, gI, gIndex, self.metaInfo.name))
 
     def setArrayValues(self, valueMetaInfo, value, offset = None, gIndex = -1):
         if gIndex == -1:
             gI = self.lastSectionGIndex
         else:
             gI = gIndex
+        try:
             self.openSections[gI].setArrayValues(valueMetaInfo, value, offset)
+        except:
+            raise Exception("Cannot set array values for metadata %s to section %d (%d) of %s, as it is not open" % (valueMetaInfo.name, gI, gIndex, self.metaInfo.name))
 
     def addArrayValues(self, valueMetaInfo, value, offset = None, gIndex = -1):
         if gIndex == -1:
             gI = self.lastSectionGIndex
         else:
             gI = gIndex
+        try:
             self.openSections[gI].addArrayValues(valueMetaInfo, value)
+        except:
+            raise Exception("Cannot add array values for metadata %s to section %d (%d) of %s, as it is not open" % (valueMetaInfo.name, gI, gIndex, self.metaInfo.name))
 
 class CachingDataManager(object):
     def __init__(self, metaInfo, superSectionManager, cachingLevel):