Haystack Data Source Plugin

This is a Grafana data source plugin that supports direct communication with a Project Haystack API Server. It handles authentication and supports standard Haystack API operations as well as custom Axon execution.

Some popular servers with Haystack APIs are:

• SkySpark
• Tridium Niagara (via NHaystack)
• Siemens Desigo Optic
• Fin Framework
• Haxall
• WideSky Cloud

Usage

Create a Data Source

Follow the Grafana instructions to create a new Haystack datasource. Next, fill in the required information:

• The name of the data source.
• The root Haystack API URL. The URLs for some popular Haystack servers are listed below:
  • SkySpark: http://<host>/api/<proj>/
  • Haxall: http://<host>/api/
  • NHaystack: http://<host>/<name_of_nhaystack_service>/
• The username and password. It is best practice to create a dedicated user for the Grafana integration.

Once complete, select Save & Test. If you get a green check mark, the connection was successful!

Query Data

To query data from the data source, create a dashboard and add a new panel.

Select your Haystack data source in the Data Sources menu. Next, select the type of Haystack query that should be performed (only queries supported by your data source are shown):

• Eval: Evaluate a free-form Axon expression. Note: Not all Haystack servers support this functionality
• HisRead: Display the history of a single point over the selected time range.
• HisRead via filter: Read multiple points using a filter, and display their histories over the selected time range.
• Read: Display the records matching a filter. Since this is not timeseries data, it is best viewed in Grafana's "Table" view.

Variable Usage

Grafana variables can be injected into Haystack queries using the ordinary syntax, e.g. $varName.

We also support a few special variables from the selected time-range:

• $__timeRange_start: DateTime start of the selected Grafana time range
• $__timeRange_end: DateTime end of the selected Grafana time range
• $__maxDataPoints: Number representing the pixel width of Grafana's display panel.
• $__interval: Number representing Grafana's recommended data interval. This is the duration of the time range, divided by the number of pixels, delivered in units of minutes.

To use them, simply enter the value in the input string. Below is an example of using the variables in an Eval query:

> read(temp).hisRead($__timeRange_start..$__timeRange_end).hisInterpolate()

Query Variables

You can use the Haystack connector to source new variables. Create a query and then enter the name of the column that contains the variable values. If no column is specified, id is used if present. Otherwise, the first column is used.

The value injected by the variable exactly matches the displayed value, with the exception of Ref types. Instead, Ref types display the "display" portion and inject only the "ID" portion (i.e. @abc "Site A" will be displayed as Site A and provide @abc when injected). Multiple-select values are combined with commas, (red,blue), but this may be customized using the advanced variable format options.

Alerting

Standard grafana alerting is supported by this data source.

Haystack Server Configuration

NHaystack

Follow the setup instructions in the nhaystack README.

Currently only Basic Auth connectivity to nhaystack is supported. Basic auth should only be enabled when Niagara web traffic is encrypted using HTTPS.

To add basic auth support, click and drag baja/AuthenticationSchemes/WebServicesSchemes/HTTPBasicScheme from the Palette to Config/AuthenticationService/AuthenticationSchemes/ in the Nav pane. Then go to Config/UserService/ in the Nav pane, create a user, and set the Authentication Scheme Name slot to HTTPBasicScheme. The user must also have an Admin role in order to access nhaystack endpoints.

The root Haystack API URL is dependent on the name given to the nhaystack service: http://<host>/<name_of_nhaystack_service>/. This service name defaults to haystack, so unless renamed the URL is http://<host>/haystack/.

Support

You can view the code, contribute, or request support on this project's GitHub repo