simplify callbacks

on Module, use one single callback list 'paramsCallback' instead of
'valueCallbacks', 'errorCallbacks'. Redesign the mechanism to
avoid most of the closures.

Change-Id: Ie7f68f6bf97ab3f3cd961faa20b0e77730e5b37d
Reviewed-on: https://forge.frm2.tum.de/review/c/secop/frappy/+/33118
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>

frappy_psi/softcal.py

@@ -27,7 +27,7 @@ import numpy as np
 from scipy.interpolate import splev, splrep  # pylint: disable=import-error
 
 from frappy.core import Attached, BoolType, Parameter, Readable, StringType, \
-    FloatRange
+    FloatRange, nopoll
 
 
 def linear(x):
@@ -195,35 +195,40 @@ class Sensor(Readable):
         if self.description == '_':
             self.description = f'{self.rawsensor!r} calibrated with curve {self.calib!r}'
 
-    def doPoll(self):
-        self.read_status()
-
     def write_calib(self, value):
         self._calib = CalCurve(value)
         return value
 
-    def update_value(self, value):
+    def _get_value(self, rawvalue):
         if self.abs:
-            value = abs(float(value))
-        self.value = self._calib(value)
-        self._value_error = None
+            rawvalue = abs(float(rawvalue))
+        return self._calib(rawvalue)
 
-    def error_update_value(self, err):
-        if self.abs and str(err) == 'R_UNDER':  # hack: ignore R_UNDER from ls370
-            self._value_error = None
-            return None
-        self._value_error = repr(err)
-        raise err
+    def _get_status(self, rawstatus):
+        return rawstatus if self._value_error is None else (self.Status.ERROR, self._value_error)
 
-    def update_status(self, value):
-        if self._value_error is None:
-            self.status = value
+    def update_value(self, rawvalue, err=None):
+        if err:
+            if self.abs and str(err) == 'R_UNDER':  # hack: ignore R_UNDER from ls370
+                self._value_error = None
+                return
+            err = repr(err)
         else:
-            self.status = self.Status.ERROR, self._value_error
+            try:
+                self.value = self._get_value(rawvalue)
+            except Exception as e:
+                err = repr(e)
+        if err != self._value_error:
+            self._value_error = err
+            self.status = self._get_status(self.rawsensor.status)
 
+    def update_status(self, rawstatus):
+        self.status = self._get_status(rawstatus)
+
+    @nopoll
     def read_value(self):
-        return self._calib(self.rawsensor.read_value())
+        return self._get_value(self.rawsensor.read_value())
 
+    @nopoll
     def read_status(self):
-        self.update_status(self.rawsensor.status)
-        return self.status
+        return self._get_status(self.rawsensor.read_status())