Server¶

Canonical path: o6.server.Server

Root shortcut: o6.Server

Server ¶

Bases: _NativeServer

High-level OPC UA server.

server = o6.Server(port=4840)
with server:
    temperature = server.addVariable("Temperature", server.objectsNode, 22.5)
    print(temperature())

Every method below returns a plain value when the server drives its own event loop, and an awaitable when it runs on an external one; see MaybeAwaitable.

See the Server guide for the whole picture, and Server callbacks for behaviour implementation.

Attributes¶

roles `instance-attribute` ¶

roles = _RoleRegistry(self)

ns `instance-attribute` ¶

ns = _ServerNamespaces(self)

T `class-attribute` `instance-attribute` ¶

T = TypeVar('T')

objectsNode `property` ¶

objectsNode

The Objects folder (i=85).

typesNode `property` ¶

typesNode

The Types folder (i=86).

serverNode `property` ¶

serverNode

The Server object (i=2253).

endpointUrl `property` ¶

endpointUrl

The local endpoint URL, built from the configured port.

Functions¶

init ¶

__init__(
    port=4840,
    logger=None,
    loop=None,
    *,
    certificate=None,
    privateKey=None,
    trustList=None,
    issuerList=None,
    revocationList=None,
    secureOnly=False,
    acceptAllCertificates=False,
    applicationUri=None,
    accessControl=None,
    allowNonePolicyPassword=False,
    rbacForAnonymous=False
)

Create a server. It is not listening until start() is called.

Parameters:

Name	Type	Description	Default
`port`	`int`	TCP port to bind.	`4840`
`logger`	`Logger \| None`	Logger for server output. Defaults to the `o6.server` logger.	`None`
`loop`	`AbstractEventLoop \| None`	Event loop to schedule non-blocking iterations on. When given, or when a running loop is detected, the server does not spawn a background thread; otherwise it creates its own loop and drives it from a daemon thread.	`None`
`certificate`	`str \| Path \| bytes \| None`	Server certificate, as a path or raw DER or PEM bytes. Encryption is configured only when a private key is given too.	`None`
`privateKey`	`str \| Path \| bytes \| None`	Matching private key, as a path or raw bytes.	`None`
`trustList`	`list[str \| Path \| bytes] \| None`	Client certificates the server trusts.	`None`
`issuerList`	`list[str \| Path \| bytes] \| None`	Issuer certificates for chain validation.	`None`
`revocationList`	`list[str \| Path \| bytes] \| None`	Certificate revocation lists.	`None`
`secureOnly`	`bool`	Refuse unencrypted connections.	`False`
`acceptAllCertificates`	`bool`	Trust every client certificate. For development only.	`False`
`applicationUri`	`str \| None`	Override the advertised application URI. It must match the URI inside the server certificate on secured endpoints.	`None`
`accessControl`	`AccessControl \| None`	An `AccessControl` subclass instance that authenticates and authorizes sessions.	`None`
`allowNonePolicyPassword`	`bool`	Permit username/password tokens on an unencrypted channel.	`False`
`rbacForAnonymous`	`bool`	Enforce role permissions for anonymous sessions. Off by default, which leaves anonymous sessions permissive.	`False`

Raises:

Type	Description
`TypeError`	`accessControl` is not an `o6.AccessControl` instance.
`PermissionError`	This build has no `server` feature entitlement.

implement ¶

implement(
    declaration: type, implementation: type | None
) -> None

implement(target: MethodNode, behavior: None) -> None

implement(target: VariableNode, behavior: Any) -> None

implement(
    target: MethodNode | NodeIdLike,
    /,
    *,
    call: Callable[..., Any] | None,
) -> None

implement(
    target: (
        VariableNode | VariableTypeNode | type | NodeIdLike
    ),
    /,
    *,
    read: (
        VariableReadCallback | None | object
    ) = _CALLBACK_UNSET,
    write: (
        VariableWriteCallback | None | object
    ) = _CALLBACK_UNSET,
) -> None

implement(
    target,
    implementation=_CALLBACK_UNSET,
    /,
    *,
    call=_CALLBACK_UNSET,
    read=_CALLBACK_UNSET,
    write=_CALLBACK_UNSET,
)

Install server-local Python behaviour on a UA type or concrete node.

implement(DeclarationType, ImplementationType) binds an undecorated Python behaviour subclass to an existing ObjectType or VariableType on this server alone. Future instances created through native APIs or an AddNodes request receive that implementation, without modifying or subclassing the UA information model. Their implementation-selected children are created before the native Mandatory children, and their ordinary Python initializer runs once, after the complete subtree exists. Because AddNodes supplies no Python arguments, that initializer must be callable without required arguments. Passing None restores the declaration's own Python type for future instances.

Passing None positionally for a concrete Method or Variable restores the callback resolution performed during construction. A concrete value positionally supplied for a Variable removes both callbacks and installs that value in native storage.

call=, read=, and write= replace or clear one callback slot on a Method, Variable, or VariableType. Existing concrete instances are never changed by a type-level update.

Parameters:

Name	Type	Description	Default
`target`	`MethodNode \| VariableNode \| VariableTypeNode \| NodeIdLike \| type`	The declared type to implement, or a concrete Method, Variable, VariableType, or NodeId-like value.	required
`implementation`	`Any`	An implementation class for a type target, `None` to reset, or a value to store for a Variable target. Cannot be combined with the keyword slots.	`_CALLBACK_UNSET`
`call`	`Callable[..., Any] \| None \| object`	Method implementation, or `None` to clear the slot.	`_CALLBACK_UNSET`
`read`	`VariableReadCallback \| None \| object`	Variable value-read implementation, or `None` to clear the slot.	`_CALLBACK_UNSET`
`write`	`VariableWriteCallback \| None \| object`	Variable value-write implementation, or `None` to clear the slot.	`_CALLBACK_UNSET`

Raises:

Type	Description
`TypeError`	An implementation class is combined with `call=`, `read=`, or `write=`; a Method is given a positional value other than `None`; or a positional value targets something that is neither a Method nor a Variable.

See Implementing behaviour and Server callbacks.

createEvent ¶

createEvent(
    eventType=ns0.objtypes.BaseEventType,
    *,
    source=ns0.instances.server,
    message="",
    severity=1,
    fields=None,
    payloadSource=None
)

Create a reusable event draft without emitting it.

emitEvent ¶

emitEvent(
    eventType=ns0.objtypes.BaseEventType,
    *,
    source=ns0.instances.server,
    message="",
    severity=1,
    fields=None,
    payloadSource=None
)

Emit an event and return its generated EventId.

start ¶

start()

Start the server networking layer.

The asyncio event loop handles all I/O, timers, and callbacks. When no running loop is detected (synchronous callers), a lightweight background daemon thread drives the loop instead.

stop ¶

stop()

Shut down the server.

enter ¶

__enter__()

Start the server and return it.

exit ¶

__exit__(exc_type, exc_val, exc_tb)

Stop the server on leaving the block, including on an exception.

aenter `async` ¶

__aenter__()

Start the server and return it.

aexit `async` ¶

__aexit__(exc_type, exc_val, exc_tb)

Stop the server on leaving the block, including on an exception.

del ¶

__del__()

addReverseConnect ¶

addReverseConnect(url, callback=None)

Register a reverse connect to a client listening at url.

The server will periodically attempt to establish a connection to the given client endpoint (e.g. opc.tcp://localhost:4841).

Parameters:

Name	Type	Description	Default
`url`	`str`	The OPC UA endpoint URL of the listening client.	required
`callback`	`Callable[[int, int], None] \| None`	Called with `(handle, state)` on every state change.	`None`

Returns:

Type	Description
`int`	A handle that can be passed to `removeReverseConnect`.

removeReverseConnect ¶

removeReverseConnect(handle)

Remove a reverse connect registration.

Parameters:

Name	Type	Description	Default
`handle`	`int`	The handle returned by `addReverseConnect`.	required

addVariable ¶

addVariable(
    name,
    parent,
    value=None,
    *,
    nodeId=None,
    dataType=None,
    typeDefinition=o6.NodeId(
        ns0.vartypes.BaseDataVariableType
    ),
    writable=True,
    historizing=False,
    ns=1
)

Add a variable node to the address space.

Parameters:

Name	Type	Description	Default
`name`	`LocalizedTextLike`	BrowseName, and DisplayName, of the Variable.	required
`parent`	`NodeIdLike`	Parent node, typically `server.objectsNode`.	required
`value`	`Any`	Initial value. Its OPC UA DataType is inferred unless `dataType` is given explicitly.	`None`
`nodeId`	`NodeIdLike \| None`	Requested NodeId. The server assigns one when omitted.	`None`
`dataType`	`NodeIdLike \| None`	Explicit DataType. Inferred from `value` when omitted.	`None`
`typeDefinition`	`NodeIdLike`	VariableType of the new node.	`NodeId(BaseDataVariableType)`
`writable`	`bool`	Whether clients may write the Variable.	`True`
`historizing`	`bool`	Whether the Variable supports historical access.	`False`
`ns`	`int`	Namespace index for the BrowseName.	`1`

Returns:

Type	Description
`VariableNode`	A handle to the new Variable node.

Raises:

Type	Description
`StatusCodeError`	The AddNodes call failed.

addObject ¶

addObject(
    name,
    parent,
    *,
    nodeId=None,
    typeDefinition=o6.NodeId(ns0.objtypes.BaseObjectType),
    ns=1
)

Add an object node to the address space.

Parameters:

Name	Type	Description	Default
`name`	`LocalizedTextLike`	BrowseName, and DisplayName, of the Object.	required
`parent`	`NodeIdLike`	Parent node.	required
`nodeId`	`NodeIdLike \| None`	Requested NodeId. The server assigns one when omitted.	`None`
`typeDefinition`	`NodeIdLike`	ObjectType of the new node. Defaults to `BaseObjectType` (`i=58`).	`NodeId(BaseObjectType)`
`ns`	`int`	Namespace index for the BrowseName.	`1`

Returns:

Type	Description
`ObjectNode`	A handle to the new Object node.

Raises:

Type	Description
`StatusCodeError`	The AddNodes call failed.

addObjectType ¶

addObjectType(
    name,
    parent=o6.NodeId(ns0.objtypes.BaseObjectType),
    *,
    nodeId=None,
    ns=1
)

Add an object type node.

Parameters:

Name	Type	Description	Default
`name`	`LocalizedTextLike`	BrowseName, and DisplayName, of the ObjectType.	required
`parent`	`NodeIdLike`	The `HasSubtype` parent. Defaults to `BaseObjectType` (`i=58`).	`NodeId(BaseObjectType)`
`nodeId`	`NodeIdLike \| None`	Requested NodeId. The server assigns one when omitted.	`None`
`ns`	`int`	Namespace index for the BrowseName.	`1`

Returns:

Type	Description
`ObjectTypeNode`	A handle to the new ObjectType node.

Raises:

Type	Description
`StatusCodeError`	The AddNodes call failed.

addVariableType ¶

addVariableType(
    name,
    parent=o6.NodeId(ns0.vartypes.BaseVariableType),
    *,
    dataType=o6.NodeId(o6.Double),
    valueRank=-1,
    nodeId=None,
    ns=1
)

Add a variable type node.

Parameters:

Name	Type	Description	Default
`name`	`LocalizedTextLike`	BrowseName, and DisplayName, of the VariableType.	required
`parent`	`NodeIdLike`	The `HasSubtype` parent. Defaults to `BaseVariableType` (`i=62`).	`NodeId(BaseVariableType)`
`dataType`	`NodeIdLike`	DataType of the value. Defaults to `Double` (`i=11`).	`NodeId(Double)`
`valueRank`	`int`	ValueRank of the value. Defaults to `-1`, a scalar.	`-1`
`nodeId`	`NodeIdLike \| None`	Requested NodeId. The server assigns one when omitted.	`None`
`ns`	`int`	Namespace index for the BrowseName.	`1`

Returns:

Type	Description
`VariableTypeNode`	A handle to the new VariableType node.

Raises:

Type	Description
`StatusCodeError`	The AddNodes call failed.

addReferenceType ¶

addReferenceType(
    name,
    parent=ns0.reftypes.NonHierarchicalReferences,
    *,
    inverseName=None,
    symmetric=False,
    abstract=False,
    nodeId=None,
    ns=1
)

Add a ReferenceType node to the address space.

Parameters:

Name	Type	Description	Default
`name`	`LocalizedTextLike`	DisplayName of the node, also used as its BrowseName.	required
`parent`	`NodeIdLike`	The `HasSubtype` parent. Defaults to `NonHierarchicalReferences`.	`NonHierarchicalReferences`
`inverseName`	`LocalizedTextLike \| None`	InverseName attribute, the name of the reverse direction. OPC UA requires it for a non-symmetric, non-abstract ReferenceType.	`None`
`symmetric`	`bool`	Declare the reference symmetric, so it reads the same in both directions and needs no InverseName.	`False`
`abstract`	`bool`	Declare the ReferenceType abstract, so only its subtypes may be used in references.	`False`
`nodeId`	`NodeIdLike \| None`	NodeId of the node. The server allocates one when omitted.	`None`
`ns`	`int`	Namespace index for the BrowseName.	`1`

Returns:

Type	Description
`ReferenceTypeNode`	A handle to the new ReferenceType node.

Raises:

Type	Description
`StatusCodeError`	The AddNodes call failed, for example because the NodeId is taken or the parent does not exist.

addView ¶

addView(
    name,
    parent=ns0.instances.views,
    *,
    eventNotifier=0,
    containsNoLoops=True,
    nodeId=None,
    ns=1
)

Add a View node to the address space.

The View starts out empty; add its members with addReference. For the declarative route, use o6.view instead.

Parameters:

Name	Type	Description	Default
`name`	`LocalizedTextLike`	DisplayName of the node, also used as its BrowseName.	required
`parent`	`NodeIdLike`	Node that organizes the View. Defaults to the standard ViewsFolder.	`views`
`eventNotifier`	`int`	EventNotifier attribute of the node.	`0`
`containsNoLoops`	`bool`	ContainsNoLoops attribute, asserting that browsing the View cannot revisit a node.	`True`
`nodeId`	`NodeIdLike \| None`	NodeId of the node. The server allocates one when omitted.	`None`
`ns`	`int`	Namespace index for the BrowseName.	`1`

Returns:

Type	Description
`ViewNode`	A handle to the new View node.

Raises:

Type	Description
`StatusCodeError`	The AddNodes call failed.

addMethod ¶

addMethod(
    name,
    parent,
    callback,
    *,
    inputArgs=None,
    outputArgs=None,
    nodeId=None,
    ns=1
)

Add a method node to the address space.

Parameters:

Name	Type	Description	Default
`name`	`LocalizedTextLike`	BrowseName, and DisplayName, of the Method.	required
`parent`	`NodeIdLike`	Parent node, typically an Object.	required
`callback`	`MethodCallback`	Called when a client invokes the Method. See `MethodCallback` for the signature.	required
`inputArgs`	`list[Argument] \| None`	InputArguments descriptors.	`None`
`outputArgs`	`list[Argument] \| None`	OutputArguments descriptors.	`None`
`nodeId`	`NodeId \| None`	Requested NodeId. The server assigns one when omitted.	`None`
`ns`	`int`	Namespace index for the BrowseName.	`1`

Returns:

Type	Description
`MethodNode`	The unbound server Method node. Invoke it with `object=parent`, or
`MethodNode`	reach it through the parent Object's dot syntax to obtain a bound
`MethodNode`	call.

Raises:

Type	Description
`StatusCodeError`	The AddNodes call failed.

addReference ¶

addReference(
    source, target, referenceType, *, forward=True
)

Add a reference between two nodes.

Parameters:

Name	Type	Description	Default
`source`	`NodeIdLike`	Source node id.	required
`target`	`NodeIdLike`	Target NodeId or ExpandedNodeId. An ExpandedNodeId may name a node on another server.	required
`referenceType`	`NodeIdLike`	Reference type NodeId.	required
`forward`	`bool`	`True` for a forward reference, `False` for inverse.	`True`

deleteReference ¶

deleteReference(
    source,
    target,
    referenceType,
    *,
    forward=True,
    bidirectional=True
)

Delete a reference between two nodes.

deleteNode ¶

deleteNode(nodeId, *, deleteReferences=True)

Delete a node from the address space.

Parameters:

Name	Type	Description	Default
`nodeId`	`NodeIdLike`	The node id to delete.	required
`deleteReferences`	`bool`	If `True` (default), also delete references pointing to the node.	`True`

call ¶

call(objectId, methodId, inputArgs=[])

Call a method node server-side with admin privileges.

Matches client.call() — returns (StatusCode, *output_arguments).

Parameters:

Name	Type	Description	Default
`objectId`	`NodeIdLike`	The Object that owns the Method.	required
`methodId`	`NodeIdLike`	The Method to invoke.	required
`inputArgs`	`list[Any]`	InputArguments values, in declaration order.	`[]`

Returns:

Type	Description
`MaybeAwaitable[tuple]`	`(statusCode, output1, output2, ...)`.

Raises:

Type	Description
`StatusCodeError`	The Call service failed.

read ¶

read(target, attr=o6.AttributeId.VALUE, *, range=None)

Read one or more node attributes from the server.

Parameters:

Name	Type	Description	Default
`target`	`NodeIdLike \| list[NodeIdLike]`	A single node id or a list of node ids.	required
`attr`	`AttributeId \| str`	The attribute to read; defaults to `o6.AttributeId.VALUE`. Can also be an attribute name string.	`VALUE`
`range`	`IndexRange \| list[IndexRange]`	An OPC UA range string, a Python slice, or a tuple of slices. A list supplies one range per target.	`None`

Returns:

Type	Description
`MaybeAwaitable[Any]`	The attribute value (or list of values when `target` is a list).

write ¶

write(
    target, value, attr=o6.AttributeId.VALUE, *, range=None
)

Write one or more node attributes on the server.

If value is a o6.DataValue, it is written directly via UA_Server_writeDataValue — preserving any explicit status code and timestamps stored in the object. Otherwise the value is wrapped in a DataValue before writing.

Parameters:

Name	Type	Description	Default
`target`	`NodeIdLike \| list[NodeIdLike]`	A single node id or a list of node ids.	required
`value`	`Any`	Value (or DataValue) to write.	required
`attr`	`AttributeId \| str`	The attribute to write; defaults to `o6.AttributeId.VALUE`.	`VALUE`
`range`	`IndexRange \| list[IndexRange]`	An OPC UA range string, a Python slice, or a tuple of slices. A list supplies one range per target.	`None`

translateBrowsePaths ¶

translateBrowsePaths(request)

Server-side translate browse paths to node ids.

Parameters:

Name	Type	Description	Default
`request`	`Any`	A `TranslateBrowsePathsToNodeIdsRequest` instance.	required

Returns:

Type	Description
`MaybeAwaitable[Any]`	The corresponding response.

findDataType ¶

findDataType(nodeId)

Look up a DataType by NodeId and return the Python type or metadata.

Parameters:

Name	Type	Description	Default
`nodeId`	`NodeIdLike`	The DataType node id to look up.	required

Returns:

Type	Description
`MaybeAwaitable[Any]`	Python type or DataType metadata for the requested NodeId.

browse ¶

browse(
    target,
    *,
    maxReferences=0,
    direction=ns0.datatypes.BrowseDirection.FORWARD,
    reftype=ns0.reftypes.HierarchicalReferences,
    refsubtypes=True,
    nodeClassMask=ns0.datatypes.NodeClass.UNSPECIFIED,
    resultMask=ns0.datatypes.BrowseResultMask(0)
)

Browse one node's references.

Parameters:

Name	Type	Description	Default
`target`	`NodeIdLike`	The node to browse from.	required
`maxReferences`	`int`	Cap on returned references. `0` means no cap, and any cap can leave a continuation point for `browseNext`.	`0`
`direction`	`BrowseDirection`	`FORWARD`, `INVERSE`, or `BOTH`.	`FORWARD`
`reftype`	`NodeIdLike`	Only follow this ReferenceType. Defaults to `HierarchicalReferences`.	`HierarchicalReferences`
`refsubtypes`	`bool`	Also follow subtypes of `reftype`.	`True`
`nodeClassMask`	`NodeClass`	Only return nodes of these NodeClasses. `UNSPECIFIED` returns all.	`UNSPECIFIED`
`resultMask`	`BrowseResultMask`	Which reference fields to fill in. `0` returns only the target NodeIds.	`BrowseResultMask(0)`

Returns:

Type	Description
`MaybeAwaitable[Any]`	The `BrowseResult`, holding the references and a continuation point
`MaybeAwaitable[Any]`	when the result was truncated.

Raises:

Type	Description
`StatusCodeError`	The Browse call failed.

browseNext ¶

browseNext(releaseContinuationPoint, continuationPoint)

Continue a truncated browse.

Parameters:

Name	Type	Description	Default
`releaseContinuationPoint`	`bool`	Discard the continuation point instead of fetching the next batch.	required
`continuationPoint`	`Any`	The continuation point from the previous result.	required

Returns:

Type	Description
`MaybeAwaitable[Any]`	The next `BrowseResult`.

Raises:

Type	Description
`StatusCodeError`	The BrowseNext call failed, for example because the continuation point expired.

browseRecursive ¶

browseRecursive(
    target,
    *,
    direction=ns0.datatypes.BrowseDirection.FORWARD,
    reftype=ns0.reftypes.HierarchicalReferences,
    refsubtypes=True,
    nodeClassMask=ns0.datatypes.NodeClass.UNSPECIFIED,
    resultMask=ns0.datatypes.BrowseResultMask(0)
)

Browse a whole subtree in one native traversal.

The arguments match browse, minus maxReferences, and the traversal is depth-unbounded, so scope it with reftype and nodeClassMask on a large address space.

Returns:

Type	Description
`MaybeAwaitable[Any]`	Every reachable node as a flat list of `ExpandedNodeId` values.

Raises:

Type	Description
`StatusCodeError`	The traversal failed.

translateBrowsePathsToNodeIds ¶

translateBrowsePathsToNodeIds(browsePath)

Resolve full BrowsePaths to NodeIds.

The raw service form. translateBrowsePaths is the convenient wrapper.

Parameters:

Name	Type	Description	Default
`browsePath`	`Any`	One `BrowsePath` or a list of them.	required

Returns:

Type	Description
`MaybeAwaitable[Any]`	One `BrowsePathResult` per requested path, each with its own
`MaybeAwaitable[Any]`	StatusCode, so unresolved paths do not fail the whole call.

Raises:

Type	Description
`StatusCodeError`	The service call itself failed.

browseSimplifiedBrowsePaths ¶

browseSimplifiedBrowsePaths(origin, browsePath)

Resolve a BrowseName chain from one node, following any hierarchy.

Simpler than a full BrowsePath: every step is just a BrowseName, matched against hierarchical references.

Parameters:

Name	Type	Description	Default
`origin`	`NodeIdLike`	The node to start from.	required
`browsePath`	`Any`	The `QualifiedName` chain to follow.	required

Returns:

Type	Description
`MaybeAwaitable[Any]`	One `BrowsePathResult` per requested path.

Raises:

Type	Description
`StatusCodeError`	The service call itself failed.

forEachChildNode ¶

forEachChildNode(nodeId, callback)

Visit every reference of one node without building a result list.

The cheapest way to walk a node's references, because nothing is allocated per reference. The callback runs on the server's event loop while the node is locked, so it must not block or call back into the server.

Parameters:

Name	Type	Description	Default
`nodeId`	`NodeIdLike`	The node whose references are visited.	required
`callback`	`Callable[[NodeId, bool, NodeId], Any]`	Called as `(childId, isInverse, referenceTypeId)` for each reference.	required

registerDiscovery ¶

registerDiscovery(url, semaphoreFilePath=None)

Register this server at a Discovery Server (LDS).

Parameters:

Name	Type	Description	Default
`url`	`str`	The LDS endpoint URL, e.g. `"opc.tcp://localhost:4840"`.	required
`semaphoreFilePath`	`str \| Path \| None`	Path to a semaphore file used to coordinate shutdown across several instances. `None` sends an empty path.	`None`

Raises:

Type	Description
`StatusCodeError`	The registration failed.

deregisterDiscovery ¶

deregisterDiscovery(url)

Deregister this server from a Discovery Server (LDS).

Should be called once during server shutdown.

Parameters:

Name	Type	Description	Default
`url`	`str`	The LDS endpoint URL that was passed to `registerDiscovery`.	required

Raises:

Type	Description
`StatusCodeError`	The deregistration failed.

setRegisterServerCallback ¶

setRegisterServerCallback(callback)

Install / remove the callback invoked when another server registers with this LDS.

The callback receives a single dict argument with keys: server_uri, product_uri, discovery_urls (list of str), last_discovery_timestamp.

Pass None to remove the callback.

setServerOnNetworkCallback ¶

setServerOnNetworkCallback(callback)

Install / remove the callback invoked when another server is detected on the network (via mDNS).

The callback receives a single dict argument with keys: record_id, server_name, discovery_url, server_capabilities (list of str), last_announce_time, next_announce_time, last_online_time, is_server_announce (bool), is_txt_received (bool).

Pass None to remove the callback. Requires UA_ENABLE_DISCOVERY_MULTICAST in the open62541 build.

createDataChangeMonitoredItem ¶

createDataChangeMonitoredItem(
    nodeId,
    callback,
    *,
    timestamps=None,
    context=None,
    samplingInterval=0.0,
    monitoringMode=None
)

Create a local DataChange o6.subscription.MonitoredItem.

callback is called as::

callback(monitoredItemId, nodeId, attributeId, data_value, context)

It may be a regular function or an async def.

deleteMonitoredItem ¶

deleteMonitoredItem(monitoredItemId)

Delete a local o6.subscription.MonitoredItem by its numeric ID.

createEventMonitoredItem ¶

createEventMonitoredItem(
    nodeId,
    callback,
    *,
    context=None,
    selectClauses=None,
    whereClause=None
)

Create a local Event o6.subscription.MonitoredItem on nodeId.

callback(monitoredItemId, event_fields, context) where event_fields is a dict {QualifiedName: value}.

createEventMonitoredItemEx ¶

createEventMonitoredItemEx(
    nodeId,
    callback,
    *,
    monitoringMode=None,
    clientHandle=0,
    samplingInterval=0.0,
    eventFilter=None,
    queueSize=0,
    discardOldest=True,
    context=None
)

Extended version of createEventMonitoredItem with full control.

Uses a MonitoredItemCreateRequest (attributeId = EventNotifier). Returns the monitoredItemId.

addRepeatedCallback ¶

addRepeatedCallback(callback, intervalMs)

Register callback to be called every intervalMs milliseconds.

Returns an opaque integer callback ID that can be passed to changeRepeatedCallbackInterval or removeCallback.

changeRepeatedCallbackInterval ¶

changeRepeatedCallbackInterval(callbackId, intervalMs)

Change the interval of an existing repeated callback.

removeCallback ¶

removeCallback(callbackId)

Remove a repeated callback by ID.

Server¶

Server ¶

Attributes¶

roles instance-attribute ¶

ns instance-attribute ¶

T class-attribute instance-attribute ¶

objectsNode property ¶

typesNode property ¶

serverNode property ¶

endpointUrl property ¶

Functions¶

__init__ ¶

implement ¶

createEvent ¶

emitEvent ¶

start ¶

stop ¶

__enter__ ¶

__exit__ ¶

__aenter__ async ¶

__aexit__ async ¶

__del__ ¶

addReverseConnect ¶

removeReverseConnect ¶

addVariable ¶

addObject ¶

addObjectType ¶

addVariableType ¶

addReferenceType ¶

addView ¶

addMethod ¶

addReference ¶

deleteReference ¶

deleteNode ¶

call ¶

read ¶

write ¶

translateBrowsePaths ¶

findDataType ¶

browse ¶

browseNext ¶

browseRecursive ¶

translateBrowsePathsToNodeIds ¶

browseSimplifiedBrowsePaths ¶

forEachChildNode ¶

registerDiscovery ¶

deregisterDiscovery ¶

setRegisterServerCallback ¶

setServerOnNetworkCallback ¶

createDataChangeMonitoredItem ¶

deleteMonitoredItem ¶

createEventMonitoredItem ¶

createEventMonitoredItemEx ¶

addRepeatedCallback ¶

changeRepeatedCallbackInterval ¶

removeCallback ¶

roles `instance-attribute` ¶

ns `instance-attribute` ¶

T `class-attribute` `instance-attribute` ¶

objectsNode `property` ¶

typesNode `property` ¶

serverNode `property` ¶

endpointUrl `property` ¶

init ¶

enter ¶

exit ¶

aenter `async` ¶

aexit `async` ¶

del ¶