Pure PHP implementation of the OPC UA protocol stack.
Connect your PHP applications to PLCs, SCADA systems, sensors, historians, and IoT devices — no C/C++ extensions, no HTTP gateways, no middleware.

Packages • Quick Start • Integrations • Why php-opcua

OPC UA (Open Platform Communications Unified Architecture) is the industry standard protocol for secure, reliable communication in industrial automation and IoT. It's used worldwide to connect PLCs, SCADA systems, sensors, robots, CNC machines, building automation, and more.

php-opcua brings this protocol to the PHP ecosystem with a complete, native binary implementation.

Package	Description
opcua-client	The core OPC UA client library. Pure PHP binary protocol implementation with support for browse, read, write, method calls, subscriptions, history read, events, alarms, and type discovery. 6 security policies, 3 authentication modes, auto-retry, fluent builders, PSR-3/PSR-14/PSR-16 integration.
opcua-cli	Command-line tool for interacting with OPC UA servers. Browse, read, write, watch values in real-time, discover endpoints, manage certificates, export address spaces, and generate PHP code from NodeSet2.xml files.
opcua-client-nodeset	Pre-generated PHP types from 51 OPC Foundation companion specifications. 338 enums, 191 typed DTOs, 191 binary codecs covering DI, Robotics, MachineTool, BACnet, MTConnect, ISA-95, PackML, PROFINET, and more.
opcua-test-suite	Docker-based OPC UA test infrastructure. 8 pre-configured servers covering all security policies, authentication methods, and ~270 test nodes. Includes a GitHub Action for CI integration.
opcua-session-manager	ReactPHP daemon that keeps OPC UA sessions alive across PHP requests via Unix socket IPC. Eliminates the per-request connection overhead (~150ms → ~5ms).

composer require php-opcua/opcua-client

Requirements: PHP 8.2+ and ext-openssl. No other extensions required.

use PhpOpcua\Client\ClientBuilder;

$client = ClientBuilder::create()
    ->connect('opc.tcp://localhost:4840');

// Read server status
$status = $client->read('i=2259');
echo $status->getValue(); // 0 = Running

$client->disconnect();

$refs = $client->browse('i=85'); // Objects folder

foreach ($refs as $ref) {
    echo "{$ref->displayName} ({$ref->nodeId})\n";
}

$results = $client->readMulti()
    ->node('i=2259')->value()
    ->node('ns=2;i=1001')->displayName()
    ->node('ns=2;s=Temperature')->value()
    ->execute();

use PhpOpcua\Client\Types\BuiltinType;

$client->write('ns=2;i=1001', 42);                      // auto-detect type
$client->write('ns=2;i=1001', 42, BuiltinType::Int32);  // explicit type

$sub = $client->createSubscription(publishingInterval: 500.0);

$client->createMonitoredItems($sub->subscriptionId, [
    ['nodeId' => 'ns=2;i=1001'],
]);

$response = $client->publish();
foreach ($response->notifications as $notif) {
    echo $notif['dataValue']->getValue() . "\n";
}

use PhpOpcua\Client\Security\SecurityPolicy;
use PhpOpcua\Client\Security\SecurityMode;

$client = ClientBuilder::create()
    ->setSecurityPolicy(SecurityPolicy::Basic256Sha256)
    ->setSecurityMode(SecurityMode::SignAndEncrypt)
    ->setClientCertificate('/certs/client.pem', '/certs/client.key', '/certs/ca.pem')
    ->setUserCredentials('operator', 'secret')
    ->connect('opc.tcp://192.168.1.100:4840');

$values = $client->historyReadRaw(
    'ns=2;i=1001',
    startTime: new DateTimeImmutable('-1 hour'),
    endTime: new DateTimeImmutable(),
);

foreach ($values as $dv) {
    echo "[{$dv->sourceTimestamp->format('H:i:s')}] {$dv->getValue()}\n";
}

Install the CLI globally or per-project:

composer require php-opcua/opcua-cli

# Browse a server
opcua-cli browse opc.tcp://localhost:4840 /Objects --recursive

# Read a value
opcua-cli read opc.tcp://localhost:4840 ns=2;i=1001

# Watch values in real-time
opcua-cli watch opc.tcp://localhost:4840 ns=2;i=1001

# Write a value
opcua-cli write opc.tcp://localhost:4840 ns=2;i=1001 42 --type=Int32

# Discover endpoints and security policies
opcua-cli endpoints opc.tcp://localhost:4840

# Export address space to NodeSet2.xml
opcua-cli dump:nodeset opc.tcp://localhost:4840 --output=MyPLC.NodeSet2.xml

# Generate PHP types from NodeSet2.xml
opcua-cli generate:nodeset MyPLC.NodeSet2.xml --output=src/Generated --namespace=App\\OpcUa

# Manage server certificate trust
opcua-cli trust opc.tcp://localhost:4840
opcua-cli trust:list
opcua-cli trust:remove ab:cd:12:34:...

All commands support --json output, full security configuration (-s, -m, --cert, --key), and debug logging (--debug, --debug-stderr, --debug-file).

composer require php-opcua/opcua-client-nodeset

51 OPC Foundation companion specifications, ready to use as typed PHP classes:

use PhpOpcua\Client\ClientBuilder;
use PhpOpcua\Nodeset\Robotics\RoboticsRegistrar;
use PhpOpcua\Nodeset\Robotics\Enums\OperationalModeEnumeration;

$client = ClientBuilder::create()
    ->loadGeneratedTypes(new RoboticsRegistrar()) // auto-loads dependencies
    ->connect('opc.tcp://192.168.1.100:4840');

$mode = $client->read('ns=2;s=OperationalMode')->getValue();
// Returns: OperationalModeEnumeration::MANUAL_HIGH_SPEED (PHP enum, not raw int)

Supported specifications include: DI (Device Integration), Robotics, MachineTool, BACnet, MTConnect, AutoID, ISA-95, PackML, MachineVision, PROFINET, I4AAS, LADS, CNC, Safety, Scales, Woodworking, and 35 more.

A Docker-based test infrastructure with 8 OPC UA servers for integration testing:

Each server exposes ~270 nodes: scalars, arrays, matrices, methods, dynamic variables, events, alarms, historical data, structured objects, and access-controlled variables.

docker compose up -d

- uses: php-opcua/opcua-test-suite@v1
  with:
    servers: 'no-security,userpass,certificate'

composer require php-opcua/laravel-opcua

use PhpOpcua\Laravel\Facades\Opcua;

$client = Opcua::connect();
$value = $client->read('i=2259');

• Named connections in config/opcua.php (like database connections)
• Automatic PSR-3 logging and PSR-16 caching via Laravel's services
• Artisan command to start the session manager daemon: php artisan opcua:session
• Transparent session persistence when the daemon is running

A Symfony bundle with equivalent DI integration is planned.

• Pure PHP — Native binary protocol. No C extensions, no FFI, no HTTP gateways, no sidecars.
• Zero runtime dependencies — Only ext-openssl. PSR-3, PSR-14, and PSR-16 are optional.
• Full protocol support — Browse, read, write, method calls, subscriptions, events, alarms, history read, type discovery, path resolution.
• Industrial-grade security — 6 security policies (None through Aes256Sha256RsaPss), 3 authentication modes, certificate trust management with TOFU support.
• Developer experience — Fluent builders, auto-batching, auto-retry, readonly DTOs, typed enums, MockClient for testing.
• Cross-platform — Linux, macOS, Windows. PHP 8.2 through 8.5.
• Session persistence — Optional ReactPHP daemon keeps connections alive across PHP requests (~150ms → ~5ms).
• 51 companion specs — Pre-generated types for DI, Robotics, MachineTool, BACnet, and more.
• Tested — 1000+ tests, 8 Docker-based test servers, CI across PHP 8.2–8.5.

Each package is released under its own license. See the individual repository for details.