QOpcUaClient#
QOpcUaClient
allows interaction with an OPC UA server. More…
Synopsis#
Properties#
Functions#
def
addNode
(nodeToAdd)def
addReference
(referenceToAdd)def
applicationIdentity
()def
authenticationInformation
()def
backend
()def
connectToEndpoint
(endpoint)def
connectionSettings
()def
deleteNode
(nodeId[, deleteTargetReferences=true])def
deleteReference
(referenceToDelete)def
disconnectFromEndpoint
()def
endpoint
()def
error
()def
findServers
(url[, localeIds=list()[, serverUris=list()]])def
isNamespaceAutoupdateEnabled
()def
namespaceArray
()def
namespaceAutoupdateInterval
()def
node
(expandedNodeId)def
node
(nodeId)def
pkiConfiguration
()def
qualifiedNameFromNamespaceUri
(namespaceUri, name[, ok=None])def
readHistoryData
(request)def
readNodeAttributes
(nodesToRead)def
requestEndpoints
(url)def
resolveExpandedNodeId
(expandedNodeId[, ok=None])def
setApplicationIdentity
(identity)def
setAuthenticationInformation
(authenticationInformation)def
setConnectionSettings
(connectionSettings)def
setNamespaceAutoupdate
(isEnabled)def
setNamespaceAutoupdateInterval
(interval)def
setPkiConfiguration
(config)def
state
()def
supportedSecurityPolicies
()def
supportedUserTokenTypes
()def
updateNamespaceArray
()def
writeNodeAttributes
(nodesToWrite)
Signals#
def
addNodeFinished
(requestedNodeId, assignedNodeId, statusCode)def
addReferenceFinished
(sourceNodeId, referenceTypeId, targetNodeId, isForwardReference, statusCode)def
connectError
(errorState)def
connected
()def
deleteNodeFinished
(nodeId, statusCode)def
deleteReferenceFinished
(sourceNodeId, referenceTypeId, targetNodeId, isForwardReference, statusCode)def
disconnected
()def
endpointsRequestFinished
(endpoints, statusCode, requestUrl)def
errorChanged
(error)def
findServersFinished
(servers, statusCode, requestUrl)def
namespaceArrayChanged
(namespaces)def
namespaceArrayUpdated
(namespaces)def
passwordForPrivateKeyRequired
(keyFilePath, password, previousTryWasInvalid)def
readNodeAttributesFinished
(results, serviceResult)def
stateChanged
(state)def
writeNodeAttributesFinished
(results, serviceResult)
Note
This documentation may contain snippets that were automatically translated from C++ to Python. We always welcome contributions to the snippet translation. If you see an issue with the translation, you can also let us know by creating a ticket on https:/bugreports.qt.io/projects/PYSIDE
Detailed Description#
QOpcUaClient#
QOpcUaClient
implements basic client capabilities to communicate with OPC UA enabled devices and applications. This includes querying a discovery server for known servers, requesting a list of endpoints from a server, connecting and disconnecting.
After successfully connecting to a server, QOpcUaClient
allows getting QOpcUaNode
objects which enable further interaction with nodes on the OPC UA server. For operations that concern multiple nodes, QOpcUaClient
offers an API which supports reading multiple attributes of multiple nodes in a single request to the server.
QOpcUaClient
also keeps a local copy of the server’s namespace array which is created after a successful connect. This information can be queried or updated while the connection lasts. The copy of the namespace array is also used for the resolution of expanded node ids and the creation of qualified names from a namespace URI.
Addressing Nodes#
For an introduction to nodes and node ids, see QOpcUaNode
.
Usage#
Create a QOpcUaClient
using QOpcUaProvider
, request a list of endpoints from the server using requestEndpoints
and call connectToEndpoint()
to connect to one of the available endpoints. After the connection is established, a QOpcUaNode
object for the root node is requested.
QOpcUaProvider provider; if (provider.availableBackends().isEmpty()) return; QOpcUaClient *client = provider.createClient(provider.availableBackends()[0]); if (!client) return; // Connect to the stateChanged signal. Compatible slots of QObjects can be used instead of a lambda. QObject::connect(client, &QOpcUaClient::stateChanged, [client](QOpcUaClient::ClientState state) { qDebug() << "Client state changed:" << state; if (state == QOpcUaClient::ClientState::Connected) { QOpcUaNode *node = client->node("ns=0;i=84"); if (node) qDebug() << "A node object has been created"; } }); QObject::connect(client, &QOpcUaClient::endpointsRequestFinished, [client](QList<QOpcUaEndpointDescription> endpoints) { qDebug() << "Endpoints returned:" << endpoints.count(); if (endpoints.size()) client->connectToEndpoint(endpoints.first()); // Connect to the first endpoint in the list }); client->requestEndpoints(QUrl("opc.tcp://127.0.0.1:4840")); // Request a list of endpoints from the server
- class PySide6.QtOpcUa.QOpcUaClient#
Note
Properties can be used directly when from __feature__ import true_property
is used or via accessor functions otherwise.
- property PᅟySide6.QtOpcUa.QOpcUaClient.error: ClientError#
This property Specifies the current error state of the client..
- Access functions:
error
()Signal
errorChanged
(error)
- property PᅟySide6.QtOpcUa.QOpcUaClient.state: ClientState#
This property Specifies the current connection state of the client..
- Access functions:
state
()Signal
stateChanged
(state)
- PySide6.QtOpcUa.QOpcUaClient.ClientState#
This enum type specifies the connection state of the client.
Constant
Description
QOpcUaClient.Disconnected
The client is not connected to a server.
QOpcUaClient.Connecting
The client is currently connecting to a server.
QOpcUaClient.Connected
The client is connected to a server.
QOpcUaClient.Closing
The client has been connected and requests a disconnect from the server.
- PySide6.QtOpcUa.QOpcUaClient.ClientError#
This enum type specifies the current error state of the client.
Constant
Description
QOpcUaClient.NoError
No error occurred.
QOpcUaClient.InvalidUrl
The url to connect to has been wrongly specified or a connection to this url failed.
QOpcUaClient.AccessDenied
An attempt to connect to a server using username/password failed due to wrong credentials.
QOpcUaClient.ConnectionError
An error occurred with the connection.
QOpcUaClient.UnknownError
An unknown error occurred.
QOpcUaClient.UnsupportedAuthenticationInformation
The given type or data of authentication information is not supported.
- PySide6.QtOpcUa.QOpcUaClient.addNode(nodeToAdd)#
- Parameters:
nodeToAdd –
PySide6.QtOpcUa.QOpcUaAddNodeItem
- Return type:
bool
Adds the node described by nodeToAdd
on the server.
Returns true
if the asynchronous call has been successfully dispatched.
The success of the operation is returned in the addNodeFinished()
signal.
The following example code adds new a Variable node on the server:
QOpcUaNodeCreationAttributes attributes; attributes.setDisplayName(QOpcUaLocalizedText("en", "My new Variable node")); attributes.setDescription(QOpcUaLocalizedText("en", "A node which has been added at runtime")); attributes.setValue(23.0, QOpcUa::Types::Double); attributes.setDataTypeId(QOpcUa::ns0ID(QOpcUa::NodeIds::Namespace0::Double)); attributes.setValueRank(-2); // Scalar or array attributes.setAccessLevel(QOpcUa::AccessLevelBit::CurrentRead); attributes.setUserAccessLevel(QOpcUa::AccessLevelBit::CurrentRead); QOpcUaAddNodeItem item; item.setParentNodeId(QOpcUaExpandedNodeId("ns=3;s=TestFolder")); item.setReferenceTypeId(QOpcUa::nodeIdFromReferenceType(QOpcUa::ReferenceTypeId::Organizes)); item.setRequestedNewNodeId(QOpcUaExpandedNodeId("ns=3;s=MyNewVariableNode")); item.setBrowseName(QOpcUaQualifiedName(3, "MyNewVariableNode")); item.setNodeClass(QOpcUa::NodeClass::Variable); item.setNodeAttributes(attributes); m_client->addNode(item);
- PySide6.QtOpcUa.QOpcUaClient.addNodeFinished(requestedNodeId, assignedNodeId, statusCode)#
- Parameters:
requestedNodeId –
PySide6.QtOpcUa.QOpcUaExpandedNodeId
assignedNodeId – str
statusCode –
UaStatusCode
This signal is emitted after an addNode()
operation has finished. requestedNodeId
is the requested node id from the addNode()
call, assignedNodeId
is the node id the server has assigned to the new node. statusCode
contains the result of the operation. If the result is Bad
, assignedNodeId
is empty and no node has been added to the server’s address space.
- PySide6.QtOpcUa.QOpcUaClient.addReference(referenceToAdd)#
- Parameters:
referenceToAdd –
PySide6.QtOpcUa.QOpcUaAddReferenceItem
- Return type:
bool
Adds the reference described by referenceToAdd
to the server.
Returns true
if the asynchronous call has been successfully dispatched.
The success of the operation is returned in the addReferenceFinished()
signal.
The following example code adds a reference to a node to the “Objects” folder:
QOpcUaAddReferenceItem item; item.setSourceNodeId(QOpcUa::namespace0Id(QOpcUa::NodeIds::Namespace0::ObjectsFolder)); item.setReferenceTypeId(QOpcUa::nodeIdFromInteger(0, static_cast<quint32>(QOpcUa::ReferenceTypeId::Organizes))); item.setIsForwardReference(true); item.setTargetNodeId(QOpcUaExpandedNodeId("ns=3;s=MyNewVariableNode")); item.setTargetNodeClass(QOpcUa::NodeClass::Variable); m_client->addReference(item);
- PySide6.QtOpcUa.QOpcUaClient.addReferenceFinished(sourceNodeId, referenceTypeId, targetNodeId, isForwardReference, statusCode)#
- Parameters:
sourceNodeId – str
referenceTypeId – str
targetNodeId –
PySide6.QtOpcUa.QOpcUaExpandedNodeId
isForwardReference – bool
statusCode –
UaStatusCode
This signal is emitted after an addReference()
operation has finished. sourceNodeId
, referenceTypeId
, targetNodeId
and isForwardReference
are the values from the addReference()
call. statusCode
contains the result of the operation.
- PySide6.QtOpcUa.QOpcUaClient.applicationIdentity()#
- Return type:
Returns the application identity of this QOpcUaClient
instance.
See also
- PySide6.QtOpcUa.QOpcUaClient.authenticationInformation()#
- Return type:
Returns the current authentication information.
See also
- PySide6.QtOpcUa.QOpcUaClient.backend()#
- Return type:
str
Returns the name of the backend used by this instance of QOpcUaClient
, e.g. “open62541”.
- PySide6.QtOpcUa.QOpcUaClient.connectError(errorState)#
- Parameters:
errorState –
PySide6.QtOpcUa.QOpcUaErrorState
This signal is emitted when an error happened during connection establishment. The parameter errorState
contains information about the error.
In case of client side errors, these can be ignored by calling setIgnoreError
on the object.
During execution of a slot connected to this signal the backend is stopped and waits for all slots to return. This allows to pop up a user dialog to ask the enduser for example if to trust an unknown certificate before the backend continues.
- PySide6.QtOpcUa.QOpcUaClient.connectToEndpoint(endpoint)#
- Parameters:
endpoint –
PySide6.QtOpcUa.QOpcUaEndpointDescription
Connects to the OPC UA endpoint given in endpoint
.
QEndpointDescription endpointDescription; ... client->connectToEndpoint(endpointDescription);
A list of available endpoints is usually obtained by calling requestEndpoints()
.
If the endpoint requires username authentication, at least a user name must be set in QOpcUaAuthenticationInformation
. Calling this function before setting an authentication information will use the anonymous authentication.
QOpcUaAuthenticationInformation authInfo; authInfo.setUsernameAuthentication("user", "password"); client->setAuthenticationInformation(authInfo);
- PySide6.QtOpcUa.QOpcUaClient.connected()#
This signal is emitted when a connection has been established.
- PySide6.QtOpcUa.QOpcUaClient.connectionSettings()#
- Return type:
Returns the connection settings for this client.
See also
- PySide6.QtOpcUa.QOpcUaClient.deleteNode(nodeId[, deleteTargetReferences=true])#
- Parameters:
nodeId – str
deleteTargetReferences – bool
- Return type:
bool
Deletes the node with node id nodeId
from the server. If deleteTargetReferences
is false
, only the references with source node nodeId
are deleted. If deleteTargetReferences
is true
, references with nodeId
as target are deleted too.
Returns true
if the asynchronous call has been successfully dispatched.
The success of the operation is returned in the deleteNodeFinished()
signal.
The following example code deletes a node and all references to it from the server:
m_client->deleteNode(QOpcUaExpandedNodeId("ns=3;s=MyNewVariableNode"), true);See also
- PySide6.QtOpcUa.QOpcUaClient.deleteNodeFinished(nodeId, statusCode)#
- Parameters:
nodeId – str
statusCode –
UaStatusCode
This signal is emitted after a deleteNode()
operation has finished. nodeId
is the node id from the deleteNode()
call. statusCode
contains the result of the operation.
- PySide6.QtOpcUa.QOpcUaClient.deleteReference(referenceToDelete)#
- Parameters:
referenceToDelete –
PySide6.QtOpcUa.QOpcUaDeleteReferenceItem
- Return type:
bool
Deletes the reference described by referenceToDelete
from the server.
Returns true
if the asynchronous call has been successfully dispatched.
The success of the operation is returned in the deleteReferenceFinished()
signal.
The following example code deletes a reference to a node from the “Objects” folder:
QOpcUaDeleteReferenceItem item; item.setSourceNodeId(QOpcUa::namespace0Id(QOpcUa::NodeIds::Namespace0::ObjectsFolder)); item.setReferenceTypeId(QOpcUa::nodeIdFromInteger(0, static_cast<quint32>(QOpcUa::ReferenceTypeId::Organizes))); item.setIsForwardReference(true); item.setTargetNodeId(QOpcUaExpandedNodeId("ns=3;s=MyNewVariableNode")); item.setDeleteBidirectional(true); m_client->deleteReference(item);
- PySide6.QtOpcUa.QOpcUaClient.deleteReferenceFinished(sourceNodeId, referenceTypeId, targetNodeId, isForwardReference, statusCode)#
- Parameters:
sourceNodeId – str
referenceTypeId – str
targetNodeId –
PySide6.QtOpcUa.QOpcUaExpandedNodeId
isForwardReference – bool
statusCode –
UaStatusCode
This signal is emitted after a deleteReference()
operation has finished. sourceNodeId
, referenceTypeId
, targetNodeId
and isForwardReference
are the values from the deleteReference()
call. statusCode
contains the result of the operation.
- PySide6.QtOpcUa.QOpcUaClient.disconnectFromEndpoint()#
Disconnects from the server.
See also
- PySide6.QtOpcUa.QOpcUaClient.disconnected()#
This signal is emitted when a connection has been closed following to a close request.
- PySide6.QtOpcUa.QOpcUaClient.endpoint()#
- Return type:
Returns the description of the endpoint the client is currently connected to or was last connected to.
- PySide6.QtOpcUa.QOpcUaClient.endpointsRequestFinished(endpoints, statusCode, requestUrl)#
- Parameters:
endpoints – .list of QOpcUaEndpointDescription
statusCode –
UaStatusCode
requestUrl –
PySide6.QtCore.QUrl
This signal is emitted after a requestEndpoints()
operation has finished. statusCode
contains the result of the operation. If the result is Good
, endpoints
contains the descriptions of all endpoints that are available on the server. requestUrl
contains the URL that was used in the requestEndpoints()
call.
- PySide6.QtOpcUa.QOpcUaClient.error()#
- Return type:
Returns the current error state of the client.
Getter of property error
.
- PySide6.QtOpcUa.QOpcUaClient.errorChanged(error)#
- Parameters:
error –
ClientError
Notification signal of property error
.
- PySide6.QtOpcUa.QOpcUaClient.findServers(url[, localeIds=list()[, serverUris=list()]])#
- Parameters:
url –
PySide6.QtCore.QUrl
localeIds – list of strings
serverUris – list of strings
- Return type:
bool
Starts an asynchronous FindServers request to read a list of known servers from a server or discovery server at url
. Returns true
if the asynchronous call has been successfully dispatched.
localeIds
can be used to select the language of the application names returned by the request. The format is specified in OPC-UA part 3, 8.4, for example “en” for English, or “de-DE” for German (Germany). If more than one locale ID is specified, the server uses the first match. If there is no match or localeIds
is empty, a default locale is chosen by the server.
serverUris
may be used to restrict the results to servers with a matching applicationUri in their application description. For example, finding the current URL of the server with the applicationUri “MyPLC”, the following call can be used:
client->findServers(discoveryServerUrl, QStringList(), QStringList({"MyPLC"}));
The results are returned in the findServersFinished()
signal.
- PySide6.QtOpcUa.QOpcUaClient.findServersFinished(servers, statusCode, requestUrl)#
- Parameters:
servers – .list of QOpcUaApplicationDescription
statusCode –
UaStatusCode
requestUrl –
PySide6.QtCore.QUrl
This signal is emitted after a findServers()
operation has finished. statusCode
contains the result of the operation. If the result is Good
, servers
contains the application descriptions of all servers known to the queried server that matched the filter criteria. requestUrl
contains the URL that was used in the findServers()
call.
- PySide6.QtOpcUa.QOpcUaClient.isNamespaceAutoupdateEnabled()#
- Return type:
bool
Returns whether autoupdate of the namespace array is enabled.
- PySide6.QtOpcUa.QOpcUaClient.namespaceArray()#
- Return type:
list of strings
Returns the cached value of the namespace array.
The value is only valid after the namespaceArrayUpdated()
signal has been emitted.
- PySide6.QtOpcUa.QOpcUaClient.namespaceArrayChanged(namespaces)#
- Parameters:
namespaces – list of strings
This signal is emitted after the namespace array has changed. namespaces
contains the content of the server’s namespace table. The index of an entry in namespaces
corresponds to the namespace index used in the node id.
- PySide6.QtOpcUa.QOpcUaClient.namespaceArrayUpdated(namespaces)#
- Parameters:
namespaces – list of strings
This signal is emitted after an updateNamespaceArray
operation has finished. namespaces
contains the content of the server’s namespace table. The index of an entry in namespaces
corresponds to the namespace index used in the node id.
If the namespace array content stays the same after the update this signal is emitted nevertheless.
- PySide6.QtOpcUa.QOpcUaClient.namespaceAutoupdateInterval()#
- Return type:
int
Returns the current revised update interval of the namespace array.
See also
setNamespaceAutoupdateInterval(int interval)
- PySide6.QtOpcUa.QOpcUaClient.node(expandedNodeId)#
- Parameters:
expandedNodeId –
PySide6.QtOpcUa.QOpcUaExpandedNodeId
- Return type:
Returns a QOpcUaNode
object associated with the OPC UA node identified by expandedNodeId
. The caller becomes owner of the node object.
If the node is not on the currently connected server, the namespace can’t be resolved, the node id is malformed or the client is not connected, nullptr
is returned.
See also
- PySide6.QtOpcUa.QOpcUaClient.node(nodeId)
- Parameters:
nodeId – str
- Return type:
Returns a QOpcUaNode
object associated with the OPC UA node identified by nodeId
. The caller becomes owner of the node object.
If the client is not connected, nullptr
is returned. The backends may also return nullptr
for other error cases (for example for a malformed node id).
- PySide6.QtOpcUa.QOpcUaClient.passwordForPrivateKeyRequired(keyFilePath, password, previousTryWasInvalid)#
- Parameters:
keyFilePath – str
password – str
previousTryWasInvalid – bool
This signal is emitted when a password for an encrypted private key is required. The parameter keyFilePath
contains the file path to key which is used. The parameter previousTryWasInvalid
is true if a previous try to decrypt the key failed (aka invalid password). The parameter password
points to a QString that has to be filled with the actual password for the key. In case the previous try failed it contains the previously used password.
During execution of a slot connected to this signal the backend is stopped and waits for all slots to return. This allows to pop up a user dialog to ask the enduser for the password.
- PySide6.QtOpcUa.QOpcUaClient.pkiConfiguration()#
- Return type:
Returns the application’s PKI configuration of this QOpcUaClient
instance.
See also
- PySide6.QtOpcUa.QOpcUaClient.qualifiedNameFromNamespaceUri(namespaceUri, name[, ok=None])#
- Parameters:
namespaceUri – str
name – str
ok – bool
- Return type:
Attempts to create a qualified name from namespaceUri
and the name string name
. Returns the resulting qualified name. An empty qualified name is returned if namespaceUri
can’t be resolved.
ok
will be set to true
if the namespace URI resolution has been successful. If the namespace URI could not be resolved, ok
will be set to false
.
- PySide6.QtOpcUa.QOpcUaClient.readHistoryData(request)#
- Parameters:
- Return type:
Starts a read raw history request
for one or multiple nodes. This is the Qt OPC UA representation for the OPC UA ReadHistory service for reading raw historical data defined in OPC-UA part 4, 5.10.3 .
The start timestamp, end timestamp, number of values per node, returnBounds and nodes to read can be specified in a QOpcUaHistoryReadRawRequest
.
Returns a QOpcUaHistoryReadResponse
which contains the state of the request if the asynchronous request has been successfully dispatched. The results are returned in the UaStatusCode serviceResult)
signal.
In the following example, the historic data from the last two days of two nodes are requested and printed. The result is limited to ten values per node.
QOpcUaHistoryReadRawRequest request( { QOpcUaReadItem("ns=1;s=myValue1"), QOpcUaReadItem("ns=1;s=myValue2") }, QDateTime::currentDateTime(), QDateTime::currentDateTime().addDays(-2), 10, true); QOpcUaHistoryReadResponse *response = m_client->readHistoryData(request); if (response) { QObject::connect(response, &QOpcUaHistoryReadResponse::readHistoryDataFinished, [] (QList<QOpcUaHistoryData> results, QOpcUa::UaStatusCode serviceResult) { if (serviceResult != QOpcUa::UaStatusCode::Good) { qWarning() << "Fetching historical data failed with:" << serviceResult; } else { for (const auto& result : results) { qInfo() << "NodeId:" << result.nodeId(); for (const auto &dataValue : result.result()) qInfo() << "Value:" << dataValue.value(); } } }); }
- PySide6.QtOpcUa.QOpcUaClient.readNodeAttributes(nodesToRead)#
- Parameters:
nodesToRead – .list of QOpcUaReadItem
- Return type:
bool
Starts a read of multiple attributes on different nodes. The node id, the attribute and an index range can be specified for every entry in nodesToRead
.
Returns true if the asynchronous request has been successfully dispatched. The results are returned in the readNodeAttributesFinished()
signal.
This read function offers an alternative way to read attributes of nodes which can be used for scenarios where the values of a large number of node attributes on different nodes must be read without requiring the other features of the QOpcUaNode
based API like monitoring for value changes. All read items in the request are sent to the server in a single request and are answered in a single response which generates a single readNodeAttributesFinished()
signal. This reduces the network overhead and the number of signal slot connections if many different nodes are involved.
In the following example, the display name attribute and the two index ranges “0:2” and “5:7” of the value attribute of the same node and the entire value attribute of a second node are read using a single service call:
QList<QOpcUaReadItem> request; request.push_back(QOpcUaReadItem("ns=1;s=MyArrayNode", QOpcUa::NodeAttribute::DisplayName)); request.push_back(QOpcUaReadItem("ns=1;s=MyArrayNode", QOpcUa::NodeAttribute::Value, "0:2")); request.push_back(QOpcUaReadItem("ns=1;s=MyArrayNode", QOpcUa::NodeAttribute::Value, "5:7")); request.push_back(QOpcUaReadItem("ns=1;s=MyScalarNode)); m_client->readNodeAttributes(request);
- PySide6.QtOpcUa.QOpcUaClient.readNodeAttributesFinished(results, serviceResult)#
- Parameters:
results – .list of QOpcUaReadResult
serviceResult –
UaStatusCode
This signal is emitted after a readNodeAttributes()
operation has finished.
The elements in results
have the same order as the elements in the request. For each requested element, there is a value together with timestamps and the status code in results
. serviceResult
contains the status code from the OPC UA Read service.
- PySide6.QtOpcUa.QOpcUaClient.requestEndpoints(url)#
- Parameters:
url –
PySide6.QtCore.QUrl
- Return type:
bool
Starts an asynchronous GetEndpoints
request to read a list of available endpoints from the server at url
. Returns true
if the asynchronous call has been successfully dispatched.
The endpoint information is returned in the endpointsRequestFinished()
signal.
- PySide6.QtOpcUa.QOpcUaClient.resolveExpandedNodeId(expandedNodeId[, ok=None])#
- Parameters:
expandedNodeId –
PySide6.QtOpcUa.QOpcUaExpandedNodeId
ok – bool
- Return type:
str
Attempts to resolve expandedNodeId
to a node id string with numeric namespace index. Returns the node id string if the conversion was successful.
An empty string is returned if the namespace index can’t be resolved or if the identifier part of the expanded node id is malformed. ok
will be set to true
if the conversion has been successful. If the expanded node id could not be resolved, ok
will be set to false
.
- PySide6.QtOpcUa.QOpcUaClient.setApplicationIdentity(identity)#
- Parameters:
identity –
PySide6.QtOpcUa.QOpcUaApplicationIdentity
Sets the application identity for this QOpcUaClient
instance to identity
.
See also
- PySide6.QtOpcUa.QOpcUaClient.setAuthenticationInformation(authenticationInformation)#
- Parameters:
authenticationInformation –
PySide6.QtOpcUa.QOpcUaAuthenticationInformation
Sets the authentication information of this client to authenticationInformation
.
- PySide6.QtOpcUa.QOpcUaClient.setConnectionSettings(connectionSettings)#
- Parameters:
connectionSettings –
PySide6.QtOpcUa.QOpcUaConnectionSettings
Sets the connection settings for this client to connectionSettings
.
Example:
QOpcUaConnectionSettings settings; // Ask the server to give localized texts in german with french as fallback settings.setSessionLocaleIds({ "de", "fr" }); // We need to call some long running methods, increase the request timeout settings.setRequestTimeout(std::chrono::minutes(2)); opcuaClient->setConnectionSettings(settings);
The values from connectionSettings
are applied to any new connections after this point.
See also
- PySide6.QtOpcUa.QOpcUaClient.setNamespaceAutoupdate(isEnabled)#
- Parameters:
isEnabled – bool
Enables automatic update of the namespace table.
Enabling this will keep the local copy of the namespace table updated automatically. namespaceArrayUpdated
will be emitted when the array changed. isEnabled
determines if autoupdate is being enabled or disabled.
A subscription will be made on the node on the server to keep track of changes. In case a server does not support subscriptions this will not work and isNamespaceAutoupdateEnabled
returns false
.
See also
- PySide6.QtOpcUa.QOpcUaClient.setNamespaceAutoupdateInterval(interval)#
- Parameters:
interval – int
Sets the interval for the namespace table subscription.
The subscription may be revised by the server.
interval
determines the interval to check for changes in milliseconds. The default is once per second.
See also
namespaceAutoupdateInterval()
setNamespaceAutoupdate(bool isEnabled)
- PySide6.QtOpcUa.QOpcUaClient.setPkiConfiguration(config)#
- Parameters:
Sets the application PKI configuration for this QOpcUaClient
instance to config
.
See also
- PySide6.QtOpcUa.QOpcUaClient.state()#
- Return type:
Getter of property state
.
- PySide6.QtOpcUa.QOpcUaClient.stateChanged(state)#
- Parameters:
state –
ClientState
Notification signal of property state
.
- PySide6.QtOpcUa.QOpcUaClient.supportedSecurityPolicies()#
- Return type:
list of strings
Returns the security policies supported by the used backend.
This function is currently available as a Technology Preview, and therefore the API and functionality provided by the function may be subject to change at any time without prior notice.
- PySide6.QtOpcUa.QOpcUaClient.supportedUserTokenTypes()#
- Return type:
.list of QOpcUaUserTokenPolicy.TokenType
Returns the user token types supported by the used backend.
This function is currently available as a Technology Preview, and therefore the API and functionality provided by the function may be subject to change at any time without prior notice.
See also
TokenType
- PySide6.QtOpcUa.QOpcUaClient.updateNamespaceArray()#
- Return type:
bool
Requests an update of the namespace array from the server. Returns true
if the operation has been successfully dispatched.
The namespaceArrayUpdated()
signal is emitted after the operation is finished.
See also
- PySide6.QtOpcUa.QOpcUaClient.writeNodeAttributes(nodesToWrite)#
- Parameters:
nodesToWrite – .list of QOpcUaWriteItem
- Return type:
bool
Starts a write for multiple attributes on different nodes. The node id, the attribute, the value, the value type and an index range can be specified for every entry in nodesToWrite
.
Returns true
if the asynchronous request has been successfully dispatched. The results are returned in the writeNodeAttributesFinished()
signal.
This write function offers an alternative way to write attributes of nodes which can be used for scenarios where the values of a large number of node attributes on different nodes must be written without requiring the other features of the QOpcUaNode
based API like monitoring for value changes. All write items in the request are sent to the server in a single request and are answered in a single response which generates a single writeNodeAttributesFinished()
signal. This reduces the network overhead and the number of signal slot connections if many different nodes are involved.
In the following example, the Values attributes of two different nodes are written in one call. The second node has an array value of which only the first two elements are overwritten:
QList<QOpcUaWriteItem> request; request.append(QOpcUaWriteItem("ns=2;s=Demo.Static.Scalar.Double", QOpcUa::NodeAttribute::Value, 23.0, QOpcUa::Types::Double)); request.append(QOpcUaWriteItem("ns=2;s=Demo.Static.Arrays.UInt32", QOpcUa::NodeAttribute::Value, QVariantList({0, 1, 2}), QOpcUa::Types::UInt32, "0:2")); m_client->writeNodeAttributes(request);
- PySide6.QtOpcUa.QOpcUaClient.writeNodeAttributesFinished(results, serviceResult)#
- Parameters:
results – .list of QOpcUaWriteResult
serviceResult –
UaStatusCode
This signal is emitted after a writeNodeAttributes()
operation has finished.
The elements in results
have the same order as the elements in the write request. They contain the value, timestamps and status code received from the server as well as the node id, attribute and index range from the write item. This facilitates matching the result with the request.
serviceResult
is the status code from the the OPC UA Write service. If serviceResult
is not Good
, the entries in results
also have an invalid status code and must not be used.
See also