node-red-contrib-haystack

Node-RED nodes for working with Project Haystack servers.

This package lets Node-RED authenticate with Haystack-compatible servers and call common Haystack HTTP API operations such as read, hisRead, eval, and pointWrite.

Supported server platforms include Haxall, FIN, SkySpark, and other Project Haystack-compatible systems.

Install

Install from the Node-RED editor:

1. Open Manage palette
2. Go to Install
3. Search for node-red-contrib-haystack
4. Click Install

Or install from the command line in your Node-RED user directory, usually ~/.node-red:

npm install node-red-contrib-haystack

Restart Node-RED after installation if required.

Nodes

This package provides the following nodes:

| Node | Description | | ---------------------- | --------------------------------------------------------------------------------- | | haystack-server | Configuration node for server URL, project path, credentials, and token caching. | | haystack-request | Generic Haystack HTTP operation node. Use this for common or custom Haystack ops. | | haystack-read | Convenience node for the read operation. | | haystack-hisread | Convenience node for the hisRead operation. | | haystack-eval | Convenience node for the eval operation. | | haystack-point-write | Convenience node for the pointWrite operation. |

Quick start

1. Add one of the Haystack nodes, for example haystack-read or haystack-eval.
2. Open the node configuration.
3. Create a new haystack-server config node from the server field.
4. Configure the connection settings.
5. Deploy the flow.

Example configuration:

Base URL:    http://haystackServer:8080
Project Path: /api/myProjectName

The first request authenticates automatically. The authentication token is cached and reused by the runtime.

Example flow

An example flow is included in the repository:

examples/demo-flow.json

Example flow preview:

After importing the flow, replace the placeholder refs with refs from your own Haystack server:

@POINT_REF
@EQUIP_REF
@WRITABLE_POINT_REF

Credentials are not included in the example flow. Configure them in the haystack-server config node after import.

Configuration

haystack-server

The haystack-server node stores the shared connection settings used by the other Haystack nodes.

| Field | Description | | ------------ | -------------------------------------------------------------------------------------------------------- | | Base URL | Server root URL or hostname, for example http://haystackServer:8080 or https://haystack.example.com. | | Project Path | Haystack HTTP API path, usually /api/{projectName}. | | Username | Username used for Haystack authentication. | | Password | Password used for Haystack authentication. |

Tip: for Haxall, the default project is commonly named sys.

Usage

Most nodes can be configured in the editor or controlled dynamically using msg.haystack.

The preferred message format is:

{
  "haystack": {
    "op": "eval",
    "expr": "readAll(point).limit(5)"
  }
}

Older flat message fields are still accepted in some places for compatibility, but new flows should use msg.haystack.

Node details

haystack-request

Generic node for calling Haystack HTTP API operations.

Supports common and custom Haystack ops using msg.haystack.op.

Common message fields:

msg.haystack.op
msg.haystack.format
msg.haystack.outputMode
msg.headers
msg.payload
msg.rawBody

Returns:

msg.payload
msg.statusCode
msg.headers

haystack-eval

Convenience node for the eval operation.

haystack-read

Convenience node for the read operation.

Supports reads by filter or record id.

haystack-hisread

Convenience node for the hisRead operation.

Supports single-point history reads.

haystack-point-write

Convenience node for the pointWrite operation.

Supported actions:

write
manualAuto
emergencyAuto

Supported result modes:

array
ack

Formats

The nodes support these Project Haystack wire formats:

| Format | Description | | ------ | ---------------------------------------------- | | Zinc | Default format for generated request bodies. | | JSON | Can be returned as a parsed JavaScript object. | | Trio | Returned as a UTF-8 string. |

Compatibility

This package is designed for platforms implementing the Project Haystack HTTP API and related Haystack protocols.

Compatible platforms include:

• Haxall
• FIN Framework
• SkySpark
• Niagara with the nHaystack driver
• other Project Haystack-compatible platforms

The nodes support Zinc, JSON, and Trio Haystack wire formats.

References

• Project Haystack
• Haxall
• nHaystack Driver

License

MIT