Improve error messages (fix #15)

sardana_tango/ctrl/TangoAttrCTCtrl.py

@@ -141,11 +141,11 @@ class TangoAttrCTController(ReadTangoAttributes, CounterTimerController):
     +) TangoAttribute - Tango attribute to retrieve the value of the counter
     +) Formula - Formula to evaluate using 'VALUE' as the tango attribute value
     As examples you could have:
-    ch1.TangoExtraAttribute = 'my/tango/device/attribute1'
+    ch1.TangoAttribute = 'my/tango/device/attribute1'
     ch1.Formula = '-1 * VALUE'
-    ch2.TangoExtraAttribute = 'my/tango/device/attribute2'
+    ch2.TangoAttribute = 'my/tango/device/attribute2'
     ch2.Formula = 'math.sqrt(VALUE)'
-    ch3.TangoExtraAttribute = 'my_other/tango/device/attribute1'
+    ch3.TangoAttribute = 'my_other/tango/device/attribute1'
     ch3.Formula = 'math.cos(VALUE)'
     """
 

sardana_tango/ctrl/TangoAttrIORCtrl.py

@@ -76,9 +76,9 @@ class TangoAttrIORController(IORegisterController):
     Each IORegisters _MUST_HAVE_ extra attributes:
     +) TangoAttribute - Tango attribute to retrieve the value of the IORegister
         As examples you could have:
-        ch1.TangoExtraAttribute = 'my/tango/device/attribute1'
-        ch2.TangoExtraAttribute = 'my/tango/device/attribute2'
-        ch3.TangoExtraAttribute = 'my_other/tango/device/attribute1'
+        ch1.TangoAttribute = 'my/tango/device/attribute1'
+        ch2.TangoAttribute = 'my/tango/device/attribute2'
+        ch3.TangoAttribute = 'my_other/tango/device/attribute1'
     Each IORegisters _MAY_HAVE_ extra attributes:
     +) Labels - Human readable tag followed to the corresponding position
             (integer) value.
@@ -169,9 +169,9 @@ def StateOne(self, axis):
                     "Not yet configured the Tango Attribute, "
                     "or cannot proxy it")
         if not lcalibration == 0 and not llabels == lcalibration:
-            return(State.Disable,
-                   "Bad configuration of the extra attributes, "
-                   "this cannot be operated")
+            return (State.Disable,
+                    "Bad configuration of the extra attributes, "
+                    "this cannot be operated")
         else:
             dev_state = dev_proxy.state()
             if readFailed and not dev_state == DevState.MOVING:
@@ -211,7 +211,7 @@ def ReadOne(self, axis):
                 try:
                     positions.index(value)
                 except Exception:
-                    raise Exception("Invalid position.")
+                    raise ValueError("Invalid position.")
                 else:
                     return value
             # case 1+fussy: the read from the attribute must be in one of the
@@ -222,17 +222,22 @@ def ReadOne(self, axis):
                         return positions[calibration.index(fussyPos)]
                 # if the loop ends, current value is not in the fussy areas.
                 self.devsExtraAttributes[axis][READFAILED] = True
-                raise Exception("Invalid position.")
+                msg = 'Value ({}) out of calibration bounds. ' \
+                      'Please review ior calibration or write a valid value ' \
+                      'to the underlying tango attribute: {}.{}'.format(
+                          value, self.devsExtraAttributes[axis][DEVICE], attr)
+                raise ValueError(msg)
             else:
                 raise Exception(
                     "Bad configuration on optional extra attributes.")
-        except Exception:
+        except Exception as e:
             self._log.error('Exception reading attribute:%s.%s'
                             % (self.devsExtraAttributes[axis][DEVICE], attr))
             try:
                 self.devsExtraAttributes[axis][READFAILED] = True
             except Exception:
                 pass
+            raise e
 
     def WriteOne(self, axis, value):
         # If Labels is well defined, the write value must be one this struct
@@ -256,7 +261,7 @@ def WriteOne(self, axis, value):
                 try:
                     positions.index(value)
                 except Exception:
-                    raise Exception("Invalid position.")
+                    raise ValueError("Invalid position.")
                 dev_proxy.write_attribute(attr, value)
             # case 1+fussy: the write to the to the IOR is translated to the
             #              central position of the calibration.
@@ -265,17 +270,18 @@ def WriteOne(self, axis, value):
                 try:
                     ior_destination = positions.index(value)
                 except Exception:
-                    raise Exception("Invalid position.")
+                    raise ValueError("Invalid position.")
                 self._log.debug("%s ior_destination = %s" % (
                     dev, ior_destination))
                 # central element
                 calibrated_position = calibration[ior_destination][1]
                 self._log.debug("%s calibrated_position = %s" % (
                     dev, calibrated_position))
                 dev_proxy.write_attribute(attr, calibrated_position)
-        except Exception:
+        except Exception as e:
             self._log.error('Exception writing attribute:%s.%s'
                             % (self.devsExtraAttributes[axis][DEVICE], attr))
+            raise e
 
     # ## #
     # Auxiliar methods for the extra attributes