class OPCUAClient:
"""
定义opcuaclient
"""
def __init__(self, url, username='', password=''):
try:
self.client = Client(url) # 初始化OPCUA客户端
if username != '' and password != '': # 初始化时如果提供用户名密码则配置
self.client.activate_session("username", "password") # 配置用户名密码
self.client.connect()
except Exception as e:
print("OPCUAClient INIT ERROR", e)
def subscribeTag(self, stringNodeID):
"""
通过StringNodeID订阅Tag
"""
tag = self.client.get_node(stringNodeID) # 获取需要读取的节点tag值
print('tag节点值：', tag)
handler = SubHandler()
subobj = self.client.create_subscription(
100, handler) # 返回一个订阅对象第一个参数为发布间隔(毫秒)
handle = subobj.subscribe_data_change(tag) # 返回可用于退订的句柄
return subobj, handle, stringNodeID # 返回的三个参数可用于取消订阅
def unsubscribeTag(self, subobj, handle):
"""
取消订阅
"""
subobj.unsubscribe(handle)
def getNodeValue(self, stringNodeID, type=1):
"""
通过StringNodeID读取节点tag值
type = 1 获取值
type = 2 获取DataValue object
"""
tag = self.client.get_node(stringNodeID)
return tag.get_value()
def setNodeValue(self, stringNodeID, value):
"""
通过StringNodeID设置节点tag值
"""
tag = self.client.get_node(stringNodeID)
tag.set_value(value) # 使用隐含变量类型设置节点值
def disconnect(self, client):
"""
断开连接
"""
return client.disconnect()
