def connect():
global client
cs = ClientSettings("myClient", [server_address])
# Uncomment below for session logging
# cs.logToStdOutLevel = loglevels.Info
max_attempts = 40
num_attempts = 0
while (True):
print "Trying to connect to the OPC UA Server. Attempt #" + str(
num_attempts)
result = None
try:
client = Client(cs)
rootNode = Address(NodeId(opcuaidentifiers.OpcUaId_RootFolder, 0),
server_uri)
result = client.browse([rootNode])
except Exception as e:
print "Got exception: " + str(e)
num_attempts = num_attempts + 1
if num_attempts > max_attempts:
msg = 'Despite ' + str(
max_attempts
) + ' attempts couldnt establish OPC UA connection: exception is ' + str(
e)
print msg
dcs_test_utils.log_detail(False, msg, '')
raise msg
time.sleep(3)
continue
print 'Connected to OPC UA Server'
return
# create the client
myClient = Client(settings)
try:
print("")
print("First option: use the convenience function \"browse()\"")
print("===================================================")
# now browse the root node
# (notice that there is also an argument called 'maxAutoBrowseNext', which we don't mention
# here because we can leave it at the default value (100), to make sure that BrowseNext is
# automatically being called for us as much as needed!)
# (notice too that you can optionally provide a BrowseConfig and a SessionConfig for
# more detailed configuration)
firstLevelBrowseResult = myClient.browse([rootNode])
# print the result
print(" - Browse result of the first level:")
print(" ---------------------------------")
print(firstLevelBrowseResult)
# we don't expect that "manual" BrowseNext calls are still needed, as the UAF will
# have done the BrowseNext calls up to 100 times automatically for us! If there would still be
# some continuation points left, then we surely have some unexpected problem!
assert len(firstLevelBrowseResult.targets[0].continuationPoint) == 0
# we can now continue browsing the other nodes that we discovered, all simultaneously!!!
noOfFoundReferences = len(firstLevelBrowseResult.targets[0].references)
newNodesToBeBrowsed = []
for i in xrange(noOfFoundReferences):
# create the client
myClient = Client(settings)
try:
print("")
print("First option: use the convenience function \"browse()\"")
print("===================================================")
# now browse the root node
# (notice that there is also an argument called 'maxAutoBrowseNext', which we don't mention
# here because we can leave it at the default value (100), to make sure that BrowseNext is
# automatically being called for us as much as needed!)
firstLevelBrowseResult = myClient.browse([rootNode])
# Notice too that you can optionally provide a BrowseSettings and/or a SessionSettings argument
# for more detailed configuration, like this:
# OPTIONAL: let's specify a small call timeout, since the UaDemoServer is running
# on the local machine anyway:
browseSettings = BrowseSettings()
browseSettings.callTimeoutSec = 2.0
# OPTIONAL: and finally let's also specify that sessions should have a timeout of 600 seconds:
sessionSettings = SessionSettings()
sessionSettings.sessionTimeoutSec = 600.0
# now call the browse() function:
myClient.browse([rootNode], browseSettings = browseSettings, sessionSettings = sessionSettings)
# print the result
print(" - Browse result of the first level:")
from pyuaf.client import Client
from pyuaf.client.settings import ClientSettings, SessionSettings
from pyuaf.util import Address, NodeId, opcuaidentifiers
import uao
server_uri = 'urn:CERN:QuasarOpcUaServer' # needs to match the factual server URI
server_address = 'opc.tcp://127.0.0.1:4841'
cs = ClientSettings("myClient", [server_address])
client = Client(cs)
# next 2 lines are not necessary but help to ensure good state of OPC-UA connectivity
rootNode = Address(NodeId(opcuaidentifiers.OpcUaId_RootFolder, 0), server_uri)
result = client.browse([rootNode])
session = uao.Session(client, server_uri)
obj = session.get_object('anObject',
2) # needs to match factuall existing object
if result.overallStatus.isNotGood():
print("Couldn't start the simulation (status=%s)" %
result.targets[0].status)
# =====================================================================================================================
print("")
print("Synchronous browsing")
print("====================")
print("")
# We may also want to
# - browse the Root node and the Demo node simultaneously
# - print the DisplayName of all nodes that we found
result = myClient.browse([address_Root, address_Demo])
print("Nodes below the Root node:")
for ref in result.targets[0].references:
print(" - %s" % ref.displayName)
print("Nodes below the Demo node:")
for ref in result.targets[1].references:
print(" - %s" % ref.displayName)
# =====================================================================================================================
print("")
print("Synchronous creating monitored data items")
print("=========================================")
print("")
settings.applicationName = "MyClient"
settings.discoveryUrls.append("opc.tcp://localhost:48010")
# create the client
myClient = Client(settings)
try:
print("")
print("First option: use the convenience function \"browse()\"")
print("===================================================")
# now browse the root node
# (notice that there is also an argument called 'maxAutoBrowseNext', which we don't mention
# here because we can leave it at the default value (100), to make sure that BrowseNext is
# automatically being called for us as much as needed!)
firstLevelBrowseResult = myClient.browse([rootNode])
# Notice too that you can optionally provide a BrowseSettings and/or a SessionSettings argument
# for more detailed configuration, like this:
# OPTIONAL: let's specify a small call timeout, since the UaDemoServer is running
# on the local machine anyway:
browseSettings = BrowseSettings()
browseSettings.callTimeoutSec = 2.0
# OPTIONAL: and finally let's also specify that sessions should have a timeout of 600 seconds:
sessionSettings = SessionSettings()
sessionSettings.sessionTimeoutSec = 600.0
# now call the browse() function:
myClient.browse([rootNode],
browseSettings=browseSettings,
sessionSettings=sessionSettings)
if result.overallStatus.isNotGood():
print("Couldn't start the simulation (status=%s)" %result.targets[0].status)
# =====================================================================================================================
print("")
print("Synchronous browsing")
print("====================")
print("")
# We may also want to
# - browse the Root node and the Demo node simultaneously
# - print the DisplayName of all nodes that we found
result = myClient.browse( [address_Root, address_Demo] )
print("Nodes below the Root node:")
for ref in result.targets[0].references:
print(" - %s" %ref.displayName)
print("Nodes below the Demo node:")
for ref in result.targets[1].references:
print(" - %s" %ref.displayName)
# =====================================================================================================================
print("")
print("Synchronous creating monitored data items")
print("=========================================")
print("")
# The client now discovers the "opc.tcp://localhost:48010", and fetches the application description
# of the UaServerCpp demo server.
# Let's print out what the client discovered:
listOfApplicationDescriptions = myClient.serversFound()
print(listOfApplicationDescriptions)
# It's a list of one server description (the demo server). It tells us the application URI, or in
# this case, the server uri:
SERVER_URI = listOfApplicationDescriptions[0].applicationUri
# Okay now that we know the server URI of the demo server, we can connect to it.
# We'll just dynamically browse the address space, and let the UAF do the connection for us:
rootNode = Address( NodeId(opcuaidentifiers.OpcUaId_RootFolder, 0), SERVER_URI )
firstLevelBrowseResult = myClient.browse([rootNode])
print("BROWSE RESULT:")
print(firstLevelBrowseResult)
# Note that the 0 is the namespace index for the OPC UA standard. It always corresponds to the
# OPC UA standard URI 'http://opcfoundation.org/UA/'
# Instead of the above, we therefore could have also specified the namespace URI:
#rootNode = Address(NodeId(opcuaidentifiers.OpcUaId_RootFolder,
# 'http://opcfoundation.org/UA/'),
# SERVER_URI)
# It woulnd't make a difference, as the UAF will automatically "translate" the namespace URI
# 'http://opcfoundation.org/UA/' to the namespace index 0 for you.
# The mapping between namespace URIs and namespace indexes is called the NamespaceArray.
# Let's print this mapping:
result = myClient.read(Address(NodeId(opcuaidentifiers.OpcUaId_Server_NamespaceArray,
pyuaf.util.constants.OPCUA_NAMESPACE_URI), # same as 'http://opcfoundation.org/UA/'
myClient = Client(settings)
try:
print("")
print("First option: use the convenience function \"browse()\"")
print("===================================================")
# now browse the root node
# (notice that there is also an argument called 'maxAutoBrowseNext', which we don't mention
# here because we can leave it at the default value (100), to make sure that BrowseNext is
# automatically being called for us as much as needed!)
# (notice too that you can optionally provide a BrowseConfig and a SessionConfig for
# more detailed configuration)
firstLevelBrowseResult = myClient.browse([rootNode])
# print the result
print(" - Browse result of the first level:")
print(" ---------------------------------")
print(firstLevelBrowseResult)
# we don't expect that "manual" BrowseNext calls are still needed, as the UAF will
# have done the BrowseNext calls up to 100 times automatically for us! If there would still be
# some continuation points left, then we surely have some unexpected problem!
assert len(firstLevelBrowseResult.targets[0].continuationPoint) == 0
# we can now continue browsing the other nodes that we discovered, all simultaneously!!!
noOfFoundReferences = len(firstLevelBrowseResult.targets[0].references)
newNodesToBeBrowsed = []
for i in xrange(noOfFoundReferences):
def connect( ):
global client
cs = ClientSettings("myClient", [server_address])
client = Client(cs)
rootNode = Address( NodeId(opcuaidentifiers.OpcUaId_RootFolder, 0), server_uri )
result=client.browse ([ rootNode ])
# The client now discovers the "opc.tcp://localhost:48010", and fetches the application description
# of the UaServerCpp demo server.
# Let's print out what the client discovered:
listOfApplicationDescriptions = myClient.serversFound()
print(listOfApplicationDescriptions)
# It's a list of one server description (the demo server). It tells us the application URI, or in
# this case, the server uri:
SERVER_URI = listOfApplicationDescriptions[0].applicationUri
# Okay now that we know the server URI of the demo server, we can connect to it.
# We'll just dynamically browse the address space, and let the UAF do the connection for us:
rootNode = Address(NodeId(opcuaidentifiers.OpcUaId_RootFolder, 0), SERVER_URI)
firstLevelBrowseResult = myClient.browse([rootNode])
print("BROWSE RESULT:")
print(firstLevelBrowseResult)
# Note that the 0 is the namespace index for the OPC UA standard. It always corresponds to the
# OPC UA standard URI 'http://opcfoundation.org/UA/'
# Instead of the above, we therefore could have also specified the namespace URI:
#rootNode = Address(NodeId(opcuaidentifiers.OpcUaId_RootFolder,
# 'http://opcfoundation.org/UA/'),
# SERVER_URI)
# It woulnd't make a difference, as the UAF will automatically "translate" the namespace URI
# 'http://opcfoundation.org/UA/' to the namespace index 0 for you.
# The mapping between namespace URIs and namespace indexes is called the NamespaceArray.
# Let's print this mapping:
result = myClient.read(
Address(
