Node Management

OPC UA servers that support dynamic address space modification allow clients to add and remove nodes and references at runtime. This library provides four methods for these operations.

Note: Not all OPC UA servers support node management. Servers that do not will return BadServiceUnsupported. Check your server's capabilities before relying on these operations.

Adding Nodes

use PhpOpcua\Client\Types\AddNodesResult;
use PhpOpcua\Client\Types\NodeClass;
use PhpOpcua\Client\Types\NodeId;
use PhpOpcua\Client\Types\QualifiedName;
use PhpOpcua\Client\Types\StatusCode;

// Add a Variable node under the Objects folder
$results = $client->addNodes([
    [
        'parentNodeId'       => 'i=85',                          // Objects folder
        'referenceTypeId'    => 'i=35',                          // Organizes
        'requestedNewNodeId' => 'ns=2;s=MyVariable',             // desired NodeId
        'browseName'         => new QualifiedName(2, 'MyVariable'),
        'nodeClass'          => NodeClass::Variable,
        'typeDefinition'     => 'i=63',                          // BaseDataVariableType
        'dataType'           => NodeId::numeric(0, 6),           // Int32
        'accessLevel'        => 3,                               // CurrentRead | CurrentWrite
    ],
]);

foreach ($results as $result) {
    if (StatusCode::isGood($result->statusCode)) {
        echo "Created: {$result->addedNodeId}\n";
    }
}

Each item in the array produces one AddNodesResult with a statusCode and the server-assigned addedNodeId.

Supported Node Classes

All 8 OPC UA node classes are supported. The library encodes class-specific attributes automatically:

Node Class	Extra Fields
Object	`eventNotifier`
Variable	`dataType`, `valueRank`, `arrayDimensions`, `accessLevel`, `userAccessLevel`, `minimumSamplingInterval`, `historizing`, `value`
Method	`executable`, `userExecutable`
ObjectType	`isAbstract`
VariableType	`dataType`, `valueRank`, `arrayDimensions`, `isAbstract`, `value`
ReferenceType	`isAbstract`, `symmetric`, `inverseName`
DataType	`isAbstract`
View	`containsNoLoops`, `eventNotifier`

Common fields for all classes: displayName, description, writeMask, userWriteMask. If displayName is omitted, the browse name is used.

Adding an Object Node

$results = $client->addNodes([
    [
        'parentNodeId'       => 'i=85',
        'referenceTypeId'    => 'i=35',
        'requestedNewNodeId' => 'ns=2;s=MyFolder',
        'browseName'         => new QualifiedName(2, 'MyFolder'),
        'nodeClass'          => NodeClass::Object,
        'typeDefinition'     => 'i=61',  // FolderType
    ],
]);

Adding Multiple Nodes

$results = $client->addNodes([
    [
        'parentNodeId'       => 'i=85',
        'referenceTypeId'    => 'i=35',
        'requestedNewNodeId' => 'ns=2;s=Node1',
        'browseName'         => new QualifiedName(2, 'Node1'),
        'nodeClass'          => NodeClass::Variable,
        'typeDefinition'     => 'i=63',
    ],
    [
        'parentNodeId'       => 'i=85',
        'referenceTypeId'    => 'i=35',
        'requestedNewNodeId' => 'ns=2;s=Node2',
        'browseName'         => new QualifiedName(2, 'Node2'),
        'nodeClass'          => NodeClass::Variable,
        'typeDefinition'     => 'i=63',
    ],
]);

// $results[0] corresponds to Node1, $results[1] to Node2

Deleting Nodes

$statusCodes = $client->deleteNodes([
    ['nodeId' => 'ns=2;s=MyVariable', 'deleteTargetReferences' => true],
    ['nodeId' => 'ns=2;s=MyFolder'],  // deleteTargetReferences defaults to true
]);

foreach ($statusCodes as $code) {
    echo StatusCode::isGood($code) ? "Deleted\n" : "Failed: " . StatusCode::getName($code) . "\n";
}

Adding References

$statusCodes = $client->addReferences([
    [
        'sourceNodeId'    => 'ns=2;s=MyFolder',
        'referenceTypeId' => NodeId::numeric(0, 35),  // Organizes
        'isForward'       => true,
        'targetNodeId'    => 'ns=2;s=MyVariable',
        'targetNodeClass' => NodeClass::Variable,
    ],
]);

Deleting References

$statusCodes = $client->deleteReferences([
    [
        'sourceNodeId'       => 'ns=2;s=MyFolder',
        'referenceTypeId'    => NodeId::numeric(0, 35),
        'isForward'          => true,
        'targetNodeId'       => 'ns=2;s=MyVariable',
        'deleteBidirectional' => true,  // also remove the inverse reference
    ],
]);

Full Example: Create, Use, and Clean Up

use PhpOpcua\Client\Types\BuiltinType;

// 1. Create a folder and a variable
$results = $client->addNodes([
    [
        'parentNodeId'       => 'i=85',
        'referenceTypeId'    => 'i=35',
        'requestedNewNodeId' => 'ns=2;s=TempFolder',
        'browseName'         => new QualifiedName(2, 'TempFolder'),
        'nodeClass'          => NodeClass::Object,
        'typeDefinition'     => 'i=61',
    ],
    [
        'parentNodeId'       => 'ns=2;s=TempFolder',
        'referenceTypeId'    => 'i=47',  // HasComponent
        'requestedNewNodeId' => 'ns=2;s=TempValue',
        'browseName'         => new QualifiedName(2, 'TempValue'),
        'nodeClass'          => NodeClass::Variable,
        'typeDefinition'     => 'i=63',
        'dataType'           => NodeId::numeric(0, 11),  // Double
        'accessLevel'        => 3,
    ],
]);

// 2. Write and read
$client->write('ns=2;s=TempValue', 23.5, BuiltinType::Double);
$dv = $client->read('ns=2;s=TempValue');
echo $dv->getValue(); // 23.5

// 3. Clean up
$client->deleteNodes([
    ['nodeId' => 'ns=2;s=TempValue'],
    ['nodeId' => 'ns=2;s=TempFolder'],
]);

Error Handling

Common status codes returned by node management operations:

Status Code	Meaning
`0x00000000` (Good)	Operation succeeded
`0x800B0000` (BadServiceUnsupported)	Server does not support this service
`0x80340000` (BadNodeIdUnknown)	Node does not exist (delete)
`0x80330000` (BadNodeIdExists)	Requested NodeId already exists (add)
`0x80480000` (BadParentNodeIdInvalid)	Parent node not found or invalid
`0x80620000` (BadReferenceNotAllowed)	Reference type not valid for the target