async def read_attributes(self, nodeids, attr):
self.logger.info("read_attributes of several nodes")
request = ua.ReadRequest()
for nodeid in nodeids:
rv = ua.ReadValueId()
rv.NodeId = nodeid
rv.AttributeId = attr
request.Parameters.NodesToRead.append(rv)
data = await self.protocol.send_request(request)
response = struct_from_binary(ua.ReadResponse, data)
response.ResponseHeader.ServiceResult.check()
return response.Results
async def read_attribute(self, attr):
"""
Read one attribute of a node
result code from server is checked and an exception is raised in case of error
"""
rv = ua.ReadValueId()
rv.NodeId = self.nodeid
rv.AttributeId = attr
params = ua.ReadParameters()
params.NodesToRead.append(rv)
result = await self.server.read(params)
result[0].StatusCode.check()
return result[0]
async def read_attributes(self, attrs):
"""
Read several attributes of a node
list of DataValue is returned
"""
params = ua.ReadParameters()
for attr in attrs:
rv = ua.ReadValueId()
rv.NodeId = self.nodeid
rv.AttributeId = attr
params.NodesToRead.append(rv)
results = await self.server.read(params)
return results
async def read_attribute(self, attr, indexrange=None):
"""
Read one attribute of a node
attributeid is a member of ua.AttributeIds
indexrange is a NumericRange (a string; e.g. "1" or "1:3".
result code from server is checked and an exception is raised in case of error
"""
rv = ua.ReadValueId()
rv.NodeId = self.nodeid
rv.AttributeId = attr
rv.IndexRange = indexrange
params = ua.ReadParameters()
params.NodesToRead.append(rv)
result = await self.server.read(params)
result[0].StatusCode.check()
return result[0]
def _make_monitored_item_request(self, node: Node, attr, mfilter, queuesize) -> ua.MonitoredItemCreateRequest:
rv = ua.ReadValueId()
rv.NodeId = node.nodeid
rv.AttributeId = attr
# rv.IndexRange //We leave it null, then the entire array is returned
mparams = ua.MonitoringParameters()
self._client_handle += 1
mparams.ClientHandle = self._client_handle
mparams.SamplingInterval = self.parameters.RequestedPublishingInterval
mparams.QueueSize = queuesize
mparams.DiscardOldest = True
if mfilter:
mparams.Filter = mfilter
mir = ua.MonitoredItemCreateRequest()
mir.ItemToMonitor = rv
mir.MonitoringMode = ua.MonitoringMode.Reporting
mir.RequestedParameters = mparams
return mir
