SEA: let tt.value be the sample temperature when dblctrl is on

for this tt has to be a frappy_psi.sea.LscDrivable

Change-Id: Ic452b39237d31a7765bc8b2f22a12c2f454fe7da

frappy_psi/sea.py

@@ -667,18 +667,22 @@ class SeaModule(Module):
                 path2param.setdefault(hdbpath, []).append((name, key))
                 attributes[key] = pobj
 
-            def rfunc(self, cmd=f'hval {base}/{path}'):
-                reply = self.io.query(cmd, True)
-                try:
-                    reply = float(reply)
-                except ValueError:
-                    pass
-                # an updateEvent will be handled before above returns
-                return reply
-
-            rfunc.poll = False
             if key != 'status' and key is not None:
-                attributes['read_' + key] = rfunc
+                rfunc = getattr(cls, f'read_{key}', None)
+                # do not override existing read method
+                if rfunc is None:
+
+                    def rfunc(self, cmd=f'hval {base}/{path}'):
+                        reply = self.io.query(cmd, True)
+                        try:
+                            reply = float(reply)
+                        except ValueError:
+                            pass
+                        # an updateEvent will be handled before above returns
+                        return reply
+
+                    rfunc.poll = False
+                    attributes['read_' + key] = rfunc
 
             if not readonly and key:
 
@@ -722,9 +726,9 @@ class SeaModule(Module):
             if sublist is None:
                 return False
             if len(sub) > 1 or 'kids' in paramdesc:
-                # avoid params from  subtrees
+                # avoid params from subtrees
                 return False
-            # this is a top paramerter without kids
+            # this is a top parameter without kids
         sublist.append(paramdesc)
         return True
 
@@ -856,9 +860,20 @@ class SeaDrivable(SeaReadable, Drivable):
 
 class LscDrivable(SeaDrivable):
     def __new__(cls, name, logger, cfgdict, srv):
-        cfgdict['rel_paths'] = [pop_cfg(cfgdict, 'sensor_path', 'tm'), '.',
-                                pop_cfg(cfgdict, 'set_path', 'set'), 'dblctrl']
-        return super().__new__(cls, name, logger, cfgdict, srv)
+        sensor_path = pop_cfg(cfgdict, 'sensor_path', 'tm')
+        set_path = pop_cfg(cfgdict, 'set_path', 'set')
+        cfgdict['rel_paths'] = ['.', sensor_path, set_path , 'dblctrl']
+        mobj = super().__new__(cls, name, logger, cfgdict, srv)
+        mobj._sensor_path = sensor_path
+
+        def ufunc(value, timestamp, readerror, self=mobj):
+            if not self.dblctrl:
+                self.update_value(value, timestamp, readerror)
+            self.announceUpdate(self._sensor_path, value, readerror, timestamp)
+
+        setattr(mobj, f'update_{sensor_path}', ufunc)
+        mobj._read_value_error = False
+        return mobj
 
     @classmethod
     def paramFilter(cls, result, paramdesc):
@@ -869,3 +884,21 @@ class LscDrivable(SeaDrivable):
             result['.'].append(paramdesc)
             return True
         return False
+
+    def update_value(self, value, timestamp, readerror):
+        self._read_value_error = readerror
+        if self.dblctrl and not readerror:
+            super().update_value(value, timestamp, readerror)
+
+    def read_value(self):
+        if self.io.syncio:
+            try:
+                if self.dblctrl and not self._read_value_error:
+                    reply = self.io.query('hval tt', True)
+                else:
+                    reply = self.io.query(f'hval tt/{self.rel_paths[1]}', True)
+            except Exception as e:
+                print(e)
+            # an updateEvent will be handled before above returns
+            return float(reply)
+        return self.value