As currently deployed at FERMI.

Makefile

+NAME = slushutter-srv
+MAIN = SLUshutter.py
+
+DIRNAME = $(NAME:-srv=)
+MODNAME = $(MAIN:.py=)
+PY_FILES += $(wildcard src/*.py)
+
+default: bin ${PY_FILES}
+	@cp ${PY_FILES} bin/${DIRNAME}
+	@echo "#!/usr/bin/env python\nimport sys\nsys.path.append(sys.path[0]+'/${DIRNAME}')\nfrom ${MODNAME} import main\nif __name__ == '__main__':\n    main()\n" > bin/${NAME}
+	@chmod +x bin/${NAME} bin/${DIRNAME}/${MAIN}
+
+bin:
+	@test -d $@ || mkdir -p $@/${DIRNAME}
+
+clean:
+	@rm -fr bin/ src/*~
+
+.PHONY: clean

README.md

+# SLU shutter
+
+slushutter-srv -> SLUshutter.py
+
+PyTango device with two commands: open(), close() that controls 
+the USER SEED LASER switch and reports the corresponding state 
+(OPEN/CLOSE).  
+
+Needed to allow the reuse of valves-like graphic inteface.  
+
+Has one device property:
+Device name of the Tango device that actually controls the shutter.
+(e.g. 'ldm/daq/executer_exp_daq' for LDM BL).  

src/SLUshutter.py

+#!/usr/bin/env python
+#       "$Name:  $";
+#       "$Header: /home/cvsadm/cvsroot/fermi/servers/slushutter/SLUshutter.py,v 1.1.1.1 2014-03-13 10:57:43 milan Exp $";
+#=============================================================================
+#
+# file :        SLUshutter.py
+#
+# description : Very simple Tango device with two basic commands:
+#               open and close and the corresponding state.
+#
+# project :     TANGO Device Server
+#
+# $Author: milan $ Elettra SCI.COMP.GROUP.
+#
+# $Revision: 1.1.1.1 $
+#
+#=============================================================================
+#
+import sys
+import PyTango
+
+#==================================================================
+#   Device States Description:
+#   DevState.INIT: Initializing device
+#   DevState.OPEN : Shutter open 
+#   DevState.CLOSE : Shutter closed
+#   DevState.FAULT : Connection lost
+#==================================================================
+class SLUshutter(PyTango.Device_4Impl):
+  
+#------------------------------------------------------------------
+#    Device constructor
+#------------------------------------------------------------------
+    def __init__(self,cl, name):
+        print 'In Device constructor'
+        PyTango.Device_4Impl.__init__(self,cl,name)
+        SLUshutter.init_device(self)
+
+#------------------------------------------------------------------
+#    Device destructor
+#------------------------------------------------------------------
+    def delete_device(self):       
+        print "[Device delete_device method] for device",self.get_name()
+
+#------------------------------------------------------------------
+#    Device initialization
+#------------------------------------------------------------------
+    def init_device(self):
+        # print "In ", self.get_name(), "::init_device()"    
+        self.set_state(PyTango.DevState.INIT)
+        self.status_string = "Initializing device..."
+        self.get_device_properties(self.get_device_class())        
+        
+        try:
+            self.shutter_proxy = PyTango.DeviceProxy(self.ShutterDevice)
+            if self.shutter_proxy.SLU_shutter_opened:
+                self.set_state(PyTango.DevState.OPEN)
+            else:
+                self.set_state(PyTango.DevState.CLOSE)
+                            
+        except PyTango.DevFailed:        
+            print 'proxy failed'
+            self.set_state(PyTango.DevState.FAULT)
+        
+        
+#------------------------------------------------------------------
+#    Always excuted hook method
+#------------------------------------------------------------------
+    def always_executed_hook(self):
+        # print "In ", self.get_name(), "::always_executed_hook()"      
+        try:
+            if self.shutter_proxy.SLU_shutter_opened:
+                self.set_state(PyTango.DevState.OPEN)
+            else:
+                self.set_state(PyTango.DevState.CLOSE)
+                            
+        except PyTango.DevFailed:        
+            print 'proxy failed'
+            self.set_state(PyTango.DevState.FAULT)       
+        
+        
+
+#==================================================================
+#
+#    SLUshutter command methods
+#
+#==================================================================        
+
+
+#------------------------------------------------------------------
+#    Open command:
+#
+#    Description: open shutter
+#------------------------------------------------------------------
+    def Open(self):
+        print "In ", self.get_name(), "::Open()"
+        try:
+            self.shutter_proxy.SLU_shutter_opened = True
+        except PyTango.DevFailed:        
+            print 'proxy failed'
+            self.set_state(PyTango.DevState.FAULT)   
+
+
+#------------------------------------------------------------------
+#    Close command:
+#
+#    Description: open shutter
+#------------------------------------------------------------------
+    def Close(self):
+        print "In ", self.get_name(), "::Close()"      
+        try:
+            self.shutter_proxy.SLU_shutter_opened = False
+        except PyTango.DevFailed:        
+            print 'proxy failed'
+            self.set_state(PyTango.DevState.FAULT)        
+
+
+#==================================================================
+#
+#    SLUshutterClass class definition
+#
+#==================================================================
+class SLUshutterClass(PyTango.DeviceClass):
+
+    #    Class Properties
+    class_property_list = {
+        }
+        
+    #    Device Properties
+    device_property_list = {
+        'ShutterDevice':
+            [PyTango.DevString,
+            'TangoDevice that controls SLU shutter.',
+            'ldm/daq/executer_exp_daq'],
+
+        }
+        
+        
+    #    Command definitions
+    cmd_list = {
+        'Open':
+            [[PyTango.DevVoid, 'Open shutter'],
+            [PyTango.DevVoid]],
+        'Close':
+            [[PyTango.DevVoid, 'Close shutter'],
+            [PyTango.DevVoid]],
+        }   
+        
+        
+#------------------------------------------------------------------
+#    SLUshutterClass Constructor
+#------------------------------------------------------------------
+    def __init__(self, name):
+        print 'In SLUshutterClass constructor'
+        PyTango.DeviceClass.__init__(self, name)
+        self.set_type(name);
+
+
+#==================================================================
+#
+#    SLUshutter class main method
+#
+#==================================================================
+if __name__ == '__main__':
+    try:
+        py = PyTango.Util(sys.argv)
+        py.add_TgClass(SLUshutterClass,SLUshutter,'SLUshutter')
+
+        U = PyTango.Util.instance()
+        U.server_init()
+        U.server_run()
+
+    except PyTango.DevFailed,e:
+        print '-------> Received a DevFailed exception:',e
+    except Exception,e:
+        print '-------> An unforeseen exception occured....',e 
+        
+        
\ No newline at end of file