""" High level interface to pure python OPC-UA server """ import logging from datetime import timedelta, datetime try: from urllib.parse import urlparse except ImportError: from urlparse import urlparse from opcua import ua # from opcua.binary_server import BinaryServer from opcua.server.binary_server_asyncio import BinaryServer from opcua.server.internal_server import InternalServer from opcua.server.event_generator import EventGenerator from opcua.server.user_manager import UserManager from opcua.server.discovery_service import LocalDiscoveryService from opcua.common.node import Node from opcua.common.subscription import Subscription from opcua.common.manage_nodes import delete_nodes from opcua.crypto import security_policies from opcua.common.event_objects import BaseEvent from opcua.common.shortcuts import Shortcuts from opcua.common.structures import load_type_definitions, load_enums from opcua.common.xmlexporter import XmlExporter from opcua.common.xmlimporter import XmlImporter from opcua.common.ua_utils import get_nodes_of_namespace use_crypto = True try: from opcua.crypto import uacrypto except ImportError: logging.getLogger(__name__).warning("cryptography is not installed, use of crypto disabled") use_crypto = False class Server(object): """ High level Server class This class creates an opcua server with default values Create your own namespace and then populate your server address space using use the get_root() or get_objects() to get Node objects. and get_event_object() to fire events. Then start server. See example_server.py All methods are threadsafe If you need more flexibility you call directly the Ua Service methods on the iserver or iserver.isession object members. During startup the standard address space will be constructed, which may be time-consuming when running a server on a less powerful device (e.g. a Raspberry Pi). In order to improve startup performance, a optional path to a cache file can be passed to the server constructor. If the parameter is defined, the address space will be loaded from the cache file or the file will be created if it does not exist yet. As a result the first startup will be even slower due to the cache file generation but all further start ups will be significantly faster. :ivar product_uri: :vartype product_uri: uri :ivar name: :vartype name: string :ivar default_timeout: timeout in milliseconds for sessions and secure channel :vartype default_timeout: int :ivar iserver: internal server object :vartype default_timeout: InternalServer :ivar bserver: binary protocol server :vartype bserver: BinaryServer :ivar nodes: shortcuts to common nodes :vartype nodes: Shortcuts """ def __init__(self, shelffile=None, iserver=None): self.logger = logging.getLogger(__name__) self.endpoint = urlparse("opc.tcp://0.0.0.0:4840/freeopcua/server/") self._application_uri = "urn:freeopcua:python:server" self.product_uri = "urn:freeopcua.github.io:python:server" self.name = "FreeOpcUa Python Server" self.manufacturer_name = "FreeOpcUa" self.application_type = ua.ApplicationType.ClientAndServer self.default_timeout = 3600000 if iserver is not None: self.iserver = iserver else: self.iserver = InternalServer(shelffile = shelffile, parent = self) self.bserver = None self._policies = [] self.nodes = Shortcuts(self.iserver.isession) # setup some expected values self.set_application_uri(self._application_uri) sa_node = self.get_node(ua.NodeId(ua.ObjectIds.Server_ServerArray)) sa_node.set_value([self._application_uri]) status_node = self.get_node(ua.NodeId(ua.ObjectIds.Server_ServerStatus)) build_node = self.get_node(ua.NodeId(ua.ObjectIds.Server_ServerStatus_BuildInfo)) status = ua.ServerStatusDataType() status.BuildInfo.ProductUri = self.product_uri status.BuildInfo.ManufacturerName = self.manufacturer_name status.BuildInfo.ProductName = self.name status.BuildInfo.SoftwareVersion = "1.0pre" status.BuildInfo.BuildNumber = "0" status.BuildInfo.BuildDate = datetime.now() status.SecondsTillShutdown = 0 status_node.set_value(status) build_node.set_value(status.BuildInfo) # enable all endpoints by default self.certificate = None self.private_key = None self.user_manager = UserManager(parent = self) self._security_policy = [ ua.SecurityPolicyType.NoSecurity, ua.SecurityPolicyType.Basic256Sha256_SignAndEncrypt, ua.SecurityPolicyType.Basic256Sha256_Sign ] self._policyIDs = ["Anonymous", "Basic256Sha256", "Username"] def __enter__(self): self.start() return self def __exit__(self, exc_type, exc_value, traceback): self.stop() @property def local_discovery_service(self): return self.iserver.local_discovery_service def load_certificate(self, path): """ load server certificate from file, either pem or der """ self.certificate = uacrypto.load_certificate(path) def load_private_key(self, path): self.private_key = uacrypto.load_private_key(path) def disable_clock(self, val=True): """ for debugging you may want to disable clock that write every second to address space """ self.iserver.disabled_clock = val def set_application_uri(self, uri): """ Set application/server URI. This uri is supposed to be unique. If you intent to register your server to a discovery server, it really should be unique in your system! default is : "urn:freeopcua:python:server" """ self._application_uri = uri ns_node = self.get_node(ua.NodeId(ua.ObjectIds.Server_NamespaceArray)) uries = ns_node.get_value() if len(uries) > 1: uries[1] = uri # application uri is always namespace 1 else: uries.append(uri) ns_node.set_value(uries) def find_servers(self, uris=None): """ find_servers. mainly implemented for symmetry with client """ if uris is None: uris = [] params = ua.FindServersParameters() params.EndpointUrl = self.endpoint.geturl() params.ServerUris = uris return self.local_discovery_service.find_servers(params) def allow_remote_admin(self, allow): """ Enable or disable the builtin Admin user from network clients """ self.user_manager.allow_remote_admin = allow def set_endpoint(self, url): self.endpoint = urlparse(url) def get_endpoints(self): return self.iserver.get_endpoints() def set_security_policy(self, security_policy): """ Method setting up the security policies for connections to the server, where security_policy is a list of integers. During server initialization, all endpoints are enabled: security_policy = [ ua.SecurityPolicyType.NoSecurity, ua.SecurityPolicyType.Basic256Sha256_SignAndEncrypt, ua.SecurityPolicyType.Basic256Sha256_Sign ] E.g. to limit the number of endpoints and disable no encryption: set_security_policy([ ua.SecurityPolicyType.Basic256Sha256_SignAndEncrypt]) """ self._security_policy = security_policy def set_security_IDs(self, policyIDs): """ Method setting up the security endpoints for identification of clients. During server object initialization, all possible endpoints are enabled: self._policyIDs = ["Anonymous", "Basic256Sha256", "Username"] E.g. to limit the number of IDs and disable anonymous clients: set_security_policy(["Basic256Sha256"]) (Implementation for ID check is currently not finalized...) """ self._policyIDs = policyIDs def _setup_server_nodes(self): # to be called just before starting server since it needs all parameters to be setup if ua.SecurityPolicyType.NoSecurity in self._security_policy: self._set_endpoints() self._policies = [ua.SecurityPolicyFactory()] if self._security_policy != [ua.SecurityPolicyType.NoSecurity]: if not (self.certificate and self.private_key): self.logger.warning("Endpoints other than open requested but private key and certificate are not set.") return if ua.SecurityPolicyType.NoSecurity in self._security_policy: self.logger.warning("Creating an open endpoint to the server, although encrypted endpoints are enabled.") if ua.SecurityPolicyType.Basic256Sha256_SignAndEncrypt in self._security_policy: self._set_endpoints(security_policies.SecurityPolicyBasic256Sha256, ua.MessageSecurityMode.SignAndEncrypt) self._policies.append(ua.SecurityPolicyFactory(security_policies.SecurityPolicyBasic256Sha256, ua.MessageSecurityMode.SignAndEncrypt, self.certificate, self.private_key) ) if ua.SecurityPolicyType.Basic256Sha256_Sign in self._security_policy: self._set_endpoints(security_policies.SecurityPolicyBasic256Sha256, ua.MessageSecurityMode.Sign) self._policies.append(ua.SecurityPolicyFactory(security_policies.SecurityPolicyBasic256Sha256, ua.MessageSecurityMode.Sign, self.certificate, self.private_key) ) def _set_endpoints(self, policy=ua.SecurityPolicy, mode=ua.MessageSecurityMode.None_): idtokens = [] if "Anonymous" in self._policyIDs: idtoken = ua.UserTokenPolicy() idtoken.PolicyId = 'anonymous' idtoken.TokenType = ua.UserTokenType.Anonymous idtokens.append(idtoken) if "Basic256Sha256" in self._policyIDs: idtoken = ua.UserTokenPolicy() idtoken.PolicyId = 'certificate_basic256sha256' idtoken.TokenType = ua.UserTokenType.Certificate idtokens.append(idtoken) if "Username" in self._policyIDs: idtoken = ua.UserTokenPolicy() idtoken.PolicyId = 'username' idtoken.TokenType = ua.UserTokenType.UserName idtokens.append(idtoken) appdesc = ua.ApplicationDescription() appdesc.ApplicationName = ua.LocalizedText(self.name) appdesc.ApplicationUri = self._application_uri appdesc.ApplicationType = self.application_type appdesc.ProductUri = self.product_uri appdesc.DiscoveryUrls.append(self.endpoint.geturl()) edp = ua.EndpointDescription() edp.EndpointUrl = self.endpoint.geturl() edp.Server = appdesc if self.certificate: edp.ServerCertificate = uacrypto.der_from_x509(self.certificate) edp.SecurityMode = mode edp.SecurityPolicyUri = policy.URI edp.UserIdentityTokens = idtokens edp.TransportProfileUri = 'http://opcfoundation.org/UA-Profile/Transport/uatcp-uasc-uabinary' edp.SecurityLevel = 0 self.iserver.add_endpoint(edp) def set_server_name(self, name): self.name = name def start(self): """ Start to listen on network """ self._setup_server_nodes() self.iserver.start() try: if not self.bserver: self.bserver = BinaryServer(self.iserver, self.endpoint.hostname, self.endpoint.port) self.bserver.set_policies(self._policies) self.bserver.set_loop(self.iserver.loop) self.bserver.start() except Exception as exp: self.iserver.stop() raise exp def stop(self): """ Stop server """ self.bserver.stop() self.iserver.stop() def get_root_node(self): """ Get Root node of server. Returns a Node object. """ return self.get_node(ua.TwoByteNodeId(ua.ObjectIds.RootFolder)) def get_objects_node(self): """ Get Objects node of server. Returns a Node object. """ return self.get_node(ua.TwoByteNodeId(ua.ObjectIds.ObjectsFolder)) def get_server_node(self): """ Get Server node of server. Returns a Node object. """ return self.get_node(ua.TwoByteNodeId(ua.ObjectIds.Server)) def get_node(self, nodeid): """ Get a specific node using NodeId object or a string representing a NodeId """ return Node(self.iserver.isession, nodeid) def create_subscription(self, period, handler): """ Create a subscription. returns a Subscription object which allow to subscribe to events or data on server period is in milliseconds handler is a python object with following methods: def datachange_notification(self, node, val, data): def event_notification(self, event): def status_change_notification(self, status): """ params = ua.CreateSubscriptionParameters() params.RequestedPublishingInterval = period params.RequestedLifetimeCount = 3000 params.RequestedMaxKeepAliveCount = 10000 params.MaxNotificationsPerPublish = 0 params.PublishingEnabled = True params.Priority = 0 return Subscription(self.iserver.isession, params, handler) def get_namespace_array(self): """ get all namespace defined in server """ ns_node = self.get_node(ua.NodeId(ua.ObjectIds.Server_NamespaceArray)) return ns_node.get_value() def register_namespace(self, uri): """ Register a new namespace. Nodes should in custom namespace, not 0. """ ns_node = self.get_node(ua.NodeId(ua.ObjectIds.Server_NamespaceArray)) uries = ns_node.get_value() if uri in uries: return uries.index(uri) uries.append(uri) ns_node.set_value(uries) return len(uries) - 1 def get_namespace_index(self, uri): """ get index of a namespace using its uri """ uries = self.get_namespace_array() return uries.index(uri) def get_event_generator(self, etype=None, emitting_node=ua.ObjectIds.Server): """ Returns an event object using an event type from address space. Use this object to fire events """ if not etype: etype = BaseEvent() return EventGenerator(self.iserver.isession, etype, emitting_node=emitting_node) def create_custom_data_type(self, idx, name, basetype=ua.ObjectIds.BaseDataType, properties=None): if properties is None: properties = [] return self._create_custom_type(idx, name, basetype, properties, [], []) def create_custom_event_type(self, idx, name, basetype=ua.ObjectIds.BaseEventType, properties=None): if properties is None: properties = [] return self._create_custom_type(idx, name, basetype, properties, [], []) def create_custom_object_type(self, idx, name, basetype=ua.ObjectIds.BaseObjectType, properties=None, variables=None, methods=None): if properties is None: properties = [] if variables is None: variables = [] if methods is None: methods = [] return self._create_custom_type(idx, name, basetype, properties, variables, methods) # def create_custom_reference_type(self, idx, name, basetype=ua.ObjectIds.BaseReferenceType, properties=[]): # return self._create_custom_type(idx, name, basetype, properties) def create_custom_variable_type(self, idx, name, basetype=ua.ObjectIds.BaseVariableType, properties=None, variables=None, methods=None): if properties is None: properties = [] if variables is None: variables = [] if methods is None: methods = [] return self._create_custom_type(idx, name, basetype, properties, variables, methods) def _create_custom_type(self, idx, name, basetype, properties, variables, methods): if isinstance(basetype, Node): base_t = basetype elif isinstance(basetype, ua.NodeId): base_t = Node(self.iserver.isession, basetype) else: base_t = Node(self.iserver.isession, ua.NodeId(basetype)) custom_t = base_t.add_object_type(idx, name) for prop in properties: datatype = None if len(prop) > 2: datatype = prop[2] custom_t.add_property(idx, prop[0], ua.get_default_value(prop[1]), varianttype=prop[1], datatype=datatype) for variable in variables: datatype = None if len(variable) > 2: datatype = variable[2] custom_t.add_variable(idx, variable[0], ua.get_default_value(variable[1]), varianttype=variable[1], datatype=datatype) for method in methods: custom_t.add_method(idx, method[0], method[1], method[2], method[3]) return custom_t def import_xml(self, path=None, xmlstring=None): """ Import nodes defined in xml """ importer = XmlImporter(self) return importer.import_xml(path, xmlstring) def export_xml(self, nodes, path): """ Export defined nodes to xml """ exp = XmlExporter(self) exp.build_etree(nodes) return exp.write_xml(path) def export_xml_by_ns(self, path, namespaces=None): """ Export nodes of one or more namespaces to an XML file. Namespaces used by nodes are always exported for consistency. Args: server: opc ua server to use path: name of the xml file to write namespaces: list of string uris or int indexes of the namespace to export, if not provide all ns are used except 0 Returns: """ if namespaces is None: namespaces = [] nodes = get_nodes_of_namespace(self, namespaces) self.export_xml(nodes, path) def delete_nodes(self, nodes, recursive=False): return delete_nodes(self.iserver.isession, nodes, recursive) def historize_node_data_change(self, node, period=timedelta(days=7), count=0): """ Start historizing supplied nodes; see history module Args: node: node or list of nodes that can be historized (variables/properties) period: time delta to store the history; older data will be deleted from the storage count: number of changes to store in the history Returns: """ nodes = node if isinstance(node, (list, tuple)) else [node] for node in nodes: self.iserver.enable_history_data_change(node, period, count) def dehistorize_node_data_change(self, node): """ Stop historizing supplied nodes; see history module Args: node: node or list of nodes that can be historized (UA variables/properties) Returns: """ nodes = node if isinstance(node, (list, tuple)) else [node] for node in nodes: self.iserver.disable_history_data_change(node) def historize_node_event(self, node, period=timedelta(days=7), count=0): """ Start historizing events from node (typically a UA object); see history module Args: node: node or list of nodes that can be historized (UA objects) period: time delta to store the history; older data will be deleted from the storage count: number of events to store in the history Returns: """ nodes = node if isinstance(node, (list, tuple)) else [node] for node in nodes: self.iserver.enable_history_event(node, period, count) def dehistorize_node_event(self, node): """ Stop historizing events from node (typically a UA object); see history module Args: node: node or list of nodes that can be historized (UA objects) Returns: """ nodes = node if isinstance(node, (list, tuple)) else [node] for node in nodes: self.iserver.disable_history_event(node) def subscribe_server_callback(self, event, handle): self.iserver.subscribe_server_callback(event, handle) def unsubscribe_server_callback(self, event, handle): self.iserver.unsubscribe_server_callback(event, handle) def link_method(self, node, callback): """ Link a python function to a UA method in the address space; required when a UA method has been imported to the address space via XML; the python executable must be linked manually Args: node: UA method node callback: python function that the UA method will call Returns: """ self.iserver.isession.add_method_callback(node.nodeid, callback) def load_type_definitions(self, nodes=None): """ load custom structures from our server. Server side this can be used to create python objects from custom structures imported through xml into server """ return load_type_definitions(self, nodes) def load_enums(self): """ load UA structures and generate python Enums in ua module for custom enums in server """ return load_enums(self) def set_attribute_value(self, nodeid, datavalue, attr=ua.AttributeIds.Value): """ directly write datavalue to the Attribute, bypasing some checks and structure creation so it is a little faster """ return self.iserver.set_attribute_value(nodeid, datavalue, attr)