Introduction

What Is This?

php-opcua/opcua-session-manager is a daemon-based session manager for opcua-client. It keeps OPC UA connections alive across PHP requests by running a long-lived ReactPHP process that holds sessions in memory, communicating with PHP applications via a Unix socket IPC protocol.

Why Do You Need It?

PHP's request/response model destroys all state — including network connections — at the end of every request. OPC UA requires a 5-step handshake costing 50–200ms that must be repeated every single time. This library eliminates that overhead: the handshake happens once, and all subsequent requests reuse the existing session.

Requirements

• PHP >= 8.2
• ext-openssl
• ext-pcntl (recommended)
• Composer

Installation

composer require php-opcua/opcua-session-manager

Quick Start

1. Start the daemon

php bin/opcua-session-manager

2. Use ManagedClient

use PhpOpcua\SessionManager\Client\ManagedClient;

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

$value = $client->read('i=2259');
echo $value->getValue();

$refs = $client->browse('i=85');
foreach ($refs as $ref) {
    echo "{$ref->displayName} ({$ref->nodeId})\n";
}

$client->disconnect();

ManagedClient implements the same OpcUaClientInterface as the direct Client. Swap one line, keep all your code.

Features

Architecture

PHP Request (short-lived)
    │
    ▼
ManagedClient (OpcUaClientInterface)
    │ JSON over Unix socket
    ▼
SessionManagerDaemon (ReactPHP)
    ├── CommandHandler (method whitelist, security)
    ├── SessionStore (in-memory registry)
    ├── TypeSerializer (JSON ↔ OPC UA types)
    │
    ▼
OPC UA Client (opcua-client v4.0.0)
    │ TCP binary protocol
    ▼
OPC UA Server

Documentation

Ecosystem