@synefex/node-red-lads

Node-RED nodes for LADS lab devices. LADS (Laboratory and Analytical Device Standard) is the OPC UA companion spec for lab instruments. One persistent session per connection, an editor-side picker that browses the device tree, and four action nodes covering read, write, method call, and state-machine operate.

Install

In your Node-RED userDir (typically ~/.node-red/):

npm install @synefex/node-red-lads

Restart Node-RED. Five new nodes appear in the palette under the Synefex LADS section.

Nodes

| Node | Purpose | |---|---| | lads-connection | LADS server connection, persistent session, auto-reconnect. Config node. | | lads-read-value | Read the Value attribute of a node. | | lads-write-value | Write a value with explicit data-type encoding. | | lads-call-method | Call a method with input args and decoded outputs. | | lads-operate | Drive the LADS FunctionalUnitState machine (Start, Stop, Abort, Hold, Resume, ...). |

Quick start

1. Drop a LADS connection config node, point it at your server's endpoint (opc.tcp://host:port), and pick the right security mode/policy + auth combination for your server.
2. Wire an inject -> LADS read -> debug flow.
3. Open the LADS read node. The picker (cascading dropdowns above the manual NodeId field) lets you browse Device -> Functional Unit -> Function -> Variable. Pick the variable you want.
4. Deploy and click inject. payload becomes the decoded value.

Picker

Open any LADS action node in the editor and the picker shows up above the manual fields:

• Device -- top-level LADS device (browsed from the connection)
• Functional Unit -- subsystem within a device (e.g. WeighingSensor)
• Function -- behavior within an FU (e.g. CurrentValue)
• Variable / Method -- the leaf you actually pick

The picker resolves to a NodeId and writes it into the manual NodeId field; the symbolic browse path is stored alongside for re-edit restoration. Picking writable variables also auto-fills the Data type dropdown on the write node.

Security

For lab devices on a trusted network, None / None / Anonymous is usually enough. Switch to Sign or Sign & Encrypt with a matching policy when the server requires it. Validated combinations:

• None / None / Anonymous
• Sign / Basic256Sha256 / Anonymous
• SignAndEncrypt / Basic256Sha256 / Anonymous
• SignAndEncrypt / Aes128_Sha256_RsaOaep / Anonymous
• SignAndEncrypt / Aes256_Sha256_RsaPss / Anonymous
• (and Username/Password variants of all of the above)

The first time a secured connection is attempted, a self-signed client certificate is generated under <userDir>/lads-pki/own/certs/. The server administrator may need to add it to the server's trust list before the connection succeeds, or you can flip on Auto-trust server certificate for lab/testing.

License

Apache License, Version 2.0. See LICENSE and NOTICE.