node-red-contrib-opcua-suite

A modern, high-performance OPC UA suite for Node-RED — built for real industrial use.

Why This Instead of node-red-contrib-opcua?

| Feature | node-red-contrib-opcua | opcua-suite | |---|---|---| | Connection Sharing | Each node = own TCP connection | All nodes share ONE connection per endpoint (ref-counted) | | Batch Read/Write | One message per variable | Single OPC UA service call via msg.items or payload object | | Item Collector | Not available | Chain opcua-item nodes visually for batch operations | | Certificate Upload | Manual file paths only | Drag & drop upload in the editor UI | | Reconnect | Basic retry | keepSessionAlive + after_reconnection session recovery + connection_failed fallback (same as node-opcua internally) | | Architecture | Separate nodes per operation | All-in-One client + dedicated Browser/Method/Event nodes | | msg.payload Object Format | Not supported | {"Temperature": "ns=1;s=Temp"} for reads, {"ns=1;s=Temp": {value: 25.5}} for writes | | Method Calls | Basic | Full typed input/output arguments with auto-detection | | History Read | Limited | Full time-range queries with maxValues | | Discovery | Not available | getendpoints, registernodes, unregisternodes, translatebrowsepath | | Status Propagation | Per-node | Shared endpoint broadcasts connected/disconnected/reconnecting to ALL nodes | | Node Count | 6+ nodes for basic ops | 7 focused nodes covering everything |

Connection Sharing in Detail

With node-red-contrib-opcua, 9 OPC UA nodes = 9 TCP connections to your server. With this suite, 9 nodes referencing the same endpoint = 1 TCP connection, ref-counted. The endpoint config node manages the shared OpcUaClientManager. When the last node closes, the connection is released.

[Client: Read] ──┐
[Client: Write] ──┤
[Client: Sub]   ──┤── Endpoint (1 shared connection) ──► OPC UA Server
[Browser]       ──┤
[Method]        ──┤
[Event]         ──┘

Installation

cd ~/.node-red
npm install node-red-contrib-opcua-suite

Nodes

opcua-endpoint (Config Node)

Shared connection configuration. All client/browser/method/event nodes referencing the same endpoint share ONE TCP connection.

| Field | Description | |---|---| | Endpoint URL | opc.tcp://localhost:4840 | | Security Mode | None, Sign, SignAndEncrypt | | Security Policy | None, Basic128Rsa15, Basic256, Basic256Sha256, Aes128/Aes256 | | Username / Password | Optional credentials | | Certificates | Drag & drop upload for client cert, private key, CA cert, X509 user token |

opcua-client (All-in-One)

Single node for all OPC UA operations. Set via msg.operation or default in config.

Read

msg.operation = "read";
msg.nodeId = "ns=2;s=Temperature";  // or msg.topic
// Output: msg.payload = value, msg.statusCode, msg.sourceTimestamp

Read Multiple (Batch)

// Array format
msg.operation = "readmultiple";
msg.items = [
    { nodeId: "ns=2;s=Var1", name: "Temperature" },
    { nodeId: "ns=2;s=Var2", name: "Pressure" }
];

// Object format (friendly names as keys)
msg.operation = "readmultiple";
msg.payload = {
    "Temperature": "ns=1;s=Scalar.Double",
    "Counter": "ns=1;s=Scalar.Int32"
};
// Output: msg.payload = [{nodeId, value, dataType, statusCode, itemName}, ...]

Write

msg.operation = "write";
msg.nodeId = "ns=2;s=Temperature";
msg.payload = 25.5;
msg.datatype = "Double";  // optional: auto-detected from JS type

Write Multiple (Batch)

// Array format
msg.operation = "writemultiple";
msg.items = [
    { nodeId: "ns=2;s=Var1", value: 25.5, datatype: "Double" },
    { nodeId: "ns=2;s=Var2", value: true, datatype: "Boolean" }
];

// Object format (nodeIds as keys)
msg.operation = "writemultiple";
msg.payload = {
    "ns=1;s=Scalar.Double": { value: 42.0, datatype: "Double" },
    "ns=1;s=Scalar.Int32": { value: 100, datatype: "Int32" }
};

Subscribe / Unsubscribe

msg.operation = "subscribe";
msg.nodeId = "ns=2;s=Temperature";
msg.interval = 500;  // sampling interval ms (default: 1000)

msg.operation = "unsubscribe";
msg.nodeId = "ns=2;s=Temperature";

Browse / Method / History / Discovery

msg.operation = "browse";       // Browse address space
msg.operation = "method";       // Call OPC UA method
msg.operation = "history";      // Read historical values
msg.operation = "getendpoints"; // Discover server endpoints
msg.operation = "readattribute";       // Read BrowseName, DisplayName, etc.
msg.operation = "registernodes";       // Register nodes for fast access
msg.operation = "unregisternodes";     // Unregister nodes
msg.operation = "translatebrowsepath"; // Translate browse path to NodeId

opcua-item (Item Collector)

Chain multiple items in series before a client node for visual batch operations.

[Inject] → [Item: Temp] → [Item: Pressure] → [Item: Speed] → [Client (readmultiple)]

Each item adds {nodeId, datatype, itemName} to msg.items. The client reads/writes all items in a single OPC UA service call.

opcua-browser

Dedicated browse node with optional recursive browsing. References an endpoint directly.

opcua-method

Dedicated method call node. Object/Method NodeIds configurable or via msg. References an endpoint directly.

opcua-event

Subscribes to OPC UA events (BaseEventType, AlarmConditionType, etc.). References an endpoint directly.

opcua-server

Embedded OPC UA server. Create address space at runtime via msg.command: addVariable, addFolder, addObject, addMethod, setValue, setWritable, raiseEvent, getServerInfo.

NodeId Formats

| Format | Example | |---|---| | String | ns=2;s=MyVariable | | Numeric | ns=2;i=1234 | | GUID | ns=2;g=550e8400-e29b-... | | Short | i=84, s=MyVar (ns=0) | | Well-known | RootFolder, ObjectsFolder, TypesFolder, Server |

DataType Auto-Detection

| JS Type | OPC UA DataType | |---|---| | boolean | Boolean | | integer number | Int32 | | float number | Double | | string | String | | Date | DateTime |

Explicit override: msg.datatype = "UInt16" or in item config.

Docker

docker compose up -d          # Start Node-RED + OPC UA test server
# Node-RED: http://localhost:1881
# Test server: opc.tcp://localhost:4841

docker compose build --no-cache && docker compose up -d --force-recreate  # Rebuild

Testing

npm test                  # 120 unit tests
node test/live-integration.js  # 36 live integration tests (requires Docker)

License

MIT

Author

blanpa