ReadHandler and WriteHandler decorators
modules with a couple of parameters with similar read_* or write_* methods may handle them by generic methods wrapped with decorators ReadHandler / WriteHandler The trinamic driver is included in this change for demonstrating how it works. In a further step, the special handling for the iohandler stuff can be moved away from secop.server and secop.params, using this feature. + fix problem on startup of trinamic driver (needs MultiEvent.queue) + some other small fixes + apply recommended functools.wraps for wrapping Change-Id: Ibfeff9209f53c47194628463466cee28366e17ac Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/27460 Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de> Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de> Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>
This commit is contained in:
@ -26,6 +26,7 @@
|
||||
import sys
|
||||
import time
|
||||
from collections import OrderedDict
|
||||
from functools import wraps
|
||||
|
||||
from secop.datatypes import ArrayOf, BoolType, EnumType, FloatRange, \
|
||||
IntRange, StatusType, StringType, TextType, TupleOf
|
||||
@ -38,6 +39,7 @@ from secop.poller import BasicPoller, Poller
|
||||
from secop.properties import HasProperties, Property
|
||||
from secop.logging import RemoteLogHandler, HasComlog
|
||||
|
||||
|
||||
Done = UniqueObject('already set')
|
||||
"""a special return value for a read/write function
|
||||
|
||||
@ -107,12 +109,14 @@ class HasAccessibles(HasProperties):
|
||||
# XXX: create getters for the units of params ??
|
||||
|
||||
# wrap of reading/writing funcs
|
||||
if isinstance(pobj, Command):
|
||||
# nothing to do for now
|
||||
if not isinstance(pobj, Parameter):
|
||||
# nothing to do for Commands
|
||||
continue
|
||||
|
||||
rfunc = getattr(cls, 'read_' + pname, None)
|
||||
# TODO: remove handler stuff here
|
||||
rfunc_handler = pobj.handler.get_read_func(cls, pname) if pobj.handler else None
|
||||
wrapped = hasattr(rfunc, '__wrapped__')
|
||||
wrapped = getattr(rfunc, 'wrapped', False) # meaning: wrapped or auto generated
|
||||
if rfunc_handler:
|
||||
if 'read_' + pname in cls.__dict__:
|
||||
if pname in cls.__dict__:
|
||||
@ -126,73 +130,78 @@ class HasAccessibles(HasProperties):
|
||||
# create wrapper except when read function is already wrapped
|
||||
if not wrapped:
|
||||
|
||||
def wrapped_rfunc(self, pname=pname, rfunc=rfunc):
|
||||
if rfunc:
|
||||
self.log.debug("call read_%s" % pname)
|
||||
if rfunc:
|
||||
|
||||
@wraps(rfunc) # handles __wrapped__ and __doc__
|
||||
def new_rfunc(self, pname=pname, rfunc=rfunc):
|
||||
try:
|
||||
value = rfunc(self)
|
||||
if value is Done: # the setter is already triggered
|
||||
value = getattr(self, pname)
|
||||
self.log.debug("read_%s returned Done (%r)" % (pname, value))
|
||||
return value
|
||||
self.log.debug("read_%s returned %r" % (pname, value))
|
||||
self.log.debug("read_%s returned %r", pname, value)
|
||||
except Exception as e:
|
||||
self.log.debug("read_%s failed %r" % (pname, e))
|
||||
self.announceUpdate(pname, None, e)
|
||||
self.log.debug("read_%s failed with %r", pname, e)
|
||||
raise
|
||||
else:
|
||||
# return cached value
|
||||
value = self.accessibles[pname].value
|
||||
self.log.debug("return cached %s = %r" % (pname, value))
|
||||
setattr(self, pname, value) # important! trigger the setter
|
||||
return value
|
||||
if value is Done:
|
||||
return getattr(self, pname)
|
||||
setattr(self, pname, value) # important! trigger the setter
|
||||
return value
|
||||
else:
|
||||
|
||||
if rfunc:
|
||||
wrapped_rfunc.__doc__ = rfunc.__doc__
|
||||
setattr(cls, 'read_' + pname, wrapped_rfunc)
|
||||
wrapped_rfunc.__wrapped__ = True
|
||||
def new_rfunc(self, pname=pname):
|
||||
return getattr(self, pname)
|
||||
|
||||
new_rfunc.__doc__ = 'auto generated read method for ' + pname
|
||||
|
||||
new_rfunc.wrapped = True # indicate to subclasses that no more wrapping is needed
|
||||
setattr(cls, 'read_' + pname, new_rfunc)
|
||||
|
||||
if not pobj.readonly:
|
||||
wfunc = getattr(cls, 'write_' + pname, None)
|
||||
wrapped = hasattr(wfunc, '__wrapped__')
|
||||
wrapped = getattr(wfunc, 'wrapped', False) # meaning: wrapped or auto generated
|
||||
if (wfunc is None or wrapped) and pobj.handler:
|
||||
# ignore the handler, if a write function is present
|
||||
# TODO: remove handler stuff here
|
||||
wfunc = pobj.handler.get_write_func(pname)
|
||||
wrapped = False
|
||||
|
||||
# create wrapper except when write function is already wrapped
|
||||
if not wrapped:
|
||||
|
||||
def wrapped_wfunc(self, value, pname=pname, wfunc=wfunc):
|
||||
pobj = self.accessibles[pname]
|
||||
if wfunc:
|
||||
self.log.debug("check and call write_%s(%r)" % (pname, value))
|
||||
if wfunc:
|
||||
|
||||
@wraps(wfunc) # handles __wrapped__ and __doc__
|
||||
def new_wfunc(self, value, pname=pname, wfunc=wfunc):
|
||||
pobj = self.accessibles[pname]
|
||||
self.log.debug('validate %r for %r', value, pname)
|
||||
# we do not need to handle errors here, we do not
|
||||
# want to make a parameter invalid, when a write failed
|
||||
value = pobj.datatype(value)
|
||||
returned_value = wfunc(self, value)
|
||||
if returned_value is Done: # the setter is already triggered
|
||||
self.log.debug('write_%s(%r) returned %r', pname, value, returned_value)
|
||||
if returned_value is Done:
|
||||
# setattr(self, pname, getattr(self, pname))
|
||||
return getattr(self, pname)
|
||||
if returned_value is not None: # goodie: accept missing return value
|
||||
value = returned_value
|
||||
else:
|
||||
self.log.debug("check %s = %r" % (pname, value))
|
||||
value = pobj.datatype(value)
|
||||
setattr(self, pname, value)
|
||||
return value
|
||||
setattr(self, pname, value) # important! trigger the setter
|
||||
return value
|
||||
else:
|
||||
|
||||
if wfunc:
|
||||
wrapped_wfunc.__doc__ = wfunc.__doc__
|
||||
setattr(cls, 'write_' + pname, wrapped_wfunc)
|
||||
wrapped_wfunc.__wrapped__ = True
|
||||
def new_wfunc(self, value, pname=pname):
|
||||
setattr(self, pname, value)
|
||||
return value
|
||||
|
||||
new_wfunc.__doc__ = 'auto generated write method for ' + pname
|
||||
|
||||
new_wfunc.wrapped = True # indicate to subclasses that no more wrapping is needed
|
||||
setattr(cls, 'write_' + pname, new_wfunc)
|
||||
|
||||
# check for programming errors
|
||||
for attrname in cls.__dict__:
|
||||
for attrname, attrvalue in cls.__dict__.items():
|
||||
prefix, _, pname = attrname.partition('_')
|
||||
if not pname:
|
||||
continue
|
||||
if prefix == 'do':
|
||||
raise ProgrammingError('%r: old style command %r not supported anymore'
|
||||
% (cls.__name__, attrname))
|
||||
if prefix in ('read', 'write') and not isinstance(accessibles.get(pname), Parameter):
|
||||
if prefix in ('read', 'write') and not getattr(attrvalue, 'wrapped', False):
|
||||
raise ProgrammingError('%s.%s defined, but %r is no parameter'
|
||||
% (cls.__name__, attrname, pname))
|
||||
|
||||
@ -394,7 +403,7 @@ class Module(HasAccessibles):
|
||||
'value and was not given in config!' % pname)
|
||||
# we do not want to call the setter for this parameter for now,
|
||||
# this should happen on the first read
|
||||
pobj.readerror = ConfigError('not initialized')
|
||||
pobj.readerror = ConfigError('parameter %r not initialized' % pname)
|
||||
# above error will be triggered on activate after startup,
|
||||
# when not all hardware parameters are read because of startup timeout
|
||||
pobj.value = pobj.datatype(pobj.datatype.default)
|
||||
@ -459,11 +468,14 @@ class Module(HasAccessibles):
|
||||
|
||||
def announceUpdate(self, pname, value=None, err=None, timestamp=None):
|
||||
"""announce a changed value or readerror"""
|
||||
|
||||
# TODO: remove readerror 'property' and replace value with exception
|
||||
pobj = self.parameters[pname]
|
||||
timestamp = timestamp or time.time()
|
||||
changed = pobj.value != value
|
||||
try:
|
||||
# store the value even in case of error
|
||||
# TODO: we should neither check limits nor convert string to float here
|
||||
pobj.value = pobj.datatype(value)
|
||||
except Exception as e:
|
||||
if not err: # do not overwrite given error
|
||||
|
||||
Reference in New Issue
Block a user