def where_clause_from_evtype(evtypes):
cf = ua.ContentFilter()
el = ua.ContentFilterElement()
# operands can be ElementOperand, LiteralOperand, AttributeOperand, SimpleAttribute
# Create a clause where the generate event type property EventType
# must be a subtype of events in evtypes argument
# the first operand is the attribute event type
op = ua.SimpleAttributeOperand()
# op.TypeDefinitionId = evtype.nodeid
op.BrowsePath.append(ua.QualifiedName("EventType", 0))
op.AttributeId = ua.AttributeIds.Value
el.FilterOperands.append(op)
# now create a list of all subtypes we want to accept
subtypes = []
for evtype in evtypes:
subtypes += [st.nodeid for st in ua_utils.get_node_subtypes(evtype)]
subtypes = list(set(subtypes)) # remove duplicates
for subtypeid in subtypes:
op = ua.LiteralOperand()
op.Value = ua.Variant(subtypeid)
el.FilterOperands.append(op)
el.FilterOperator = ua.FilterOperator.InList
cf.Elements.append(el)
return cf
def select_clauses_from_evtype(evtype):
clauses = []
for prop in get_event_properties_from_type_node(evtype):
op = ua.SimpleAttributeOperand()
op.TypeDefinitionId = evtype.nodeid
op.AttributeId = ua.AttributeIds.Value
op.BrowsePath = [prop.get_browse_name()]
clauses.append(op)
return clauses
def _get_filter_from_event_type(self, eventtype):
eventtype = self._get_node(eventtype)
evfilter = ua.EventFilter()
for desc in eventtype.get_children_descriptions(refs=ua.ObjectIds.HasProperty, nodeclassmask=ua.NodeClass.Variable):
op = ua.SimpleAttributeOperand()
op.TypeDefinitionId = eventtype.nodeid
op.AttributeId = AttributeIds.Value
op.BrowsePath = [desc.BrowseName]
evfilter.SelectClauses.append(op)
return evfilter
def select_clauses_from_evtype(evtypes):
clauses = []
selected_paths = []
for evtype in evtypes:
for prop in get_event_properties_from_type_node(evtype):
if prop.get_browse_name() not in selected_paths:
op = ua.SimpleAttributeOperand()
op.AttributeId = ua.AttributeIds.Value
op.BrowsePath = [prop.get_browse_name()]
clauses.append(op)
selected_paths.append(prop.get_browse_name())
return clauses
def where_clause_from_evtype(evtype):
cf = ua.ContentFilter()
el = ua.ContentFilterElement()
# operands can be ElementOperand, LiteralOperand, AttributeOperand, SimpleAttribute
op = ua.SimpleAttributeOperand()
op.TypeDefinitionId = evtype.nodeid
op.BrowsePath.append(ua.QualifiedName("EventType", 0))
op.AttributeId = ua.AttributeIds.Value
el.FilterOperands.append(op)
for subtypeid in [st.nodeid for st in get_node_subtypes(evtype)]:
op = ua.LiteralOperand()
op.Value = ua.Variant(subtypeid)
el.FilterOperands.append(op)
el.FilterOperator = ua.FilterOperator.InList
cf.Elements.append(el)
return cf
def test_where_clause(self):
cf = ua.ContentFilter()
el = ua.ContentFilterElement()
op = ua.SimpleAttributeOperand()
op.BrowsePath.append(ua.QualifiedName("property", 2))
el.FilterOperands.append(op)
for i in range(10):
op = ua.LiteralOperand()
op.Value = ua.Variant(i)
el.FilterOperands.append(op)
el.FilterOperator = ua.FilterOperator.InList
cf.Elements.append(el)
wce = WhereClauseEvaluator(logging.getLogger(__name__), None, cf)
ev = BaseEvent()
ev._freeze = False
ev.property = 3
self.assertTrue(wce.eval(ev))
