Is there a concrete example of using the Haystack API in Niagara to read a data point?

Hi Ian,

Can you clarify what you are looking for?

Are you looking for code?

A Niagara Station?

A SkySpark project?

Something else?

Cheers, Richard

Hi Richard,

Thanks for the reply. I have a Niagara Station and I want to bring that data to an remote web server where I have a dashboarding UI.

Let's say I have a point called "Ramp" where n:name="Ramp".

My station url is http://station.com.

What would the script be to subscribe to the Ramp point from my dashboard HTML server?

Thanks! -Ian

I suppose I am looking for an ops example to read a point.

Hi Ian,

The first thing to understand is that you in your post above you have used a NEQL query. Haystack and NEQL queries are slightly different and NEQL queries are not supported via the REST API.

If you wish to do a single Read on a point then you should look at the Read Op in the Haystack REST API.

If you wish to subscribe to a point via the REST API then you should look at the Watch Ops (there are multiple endpoints).

For reading histories or trend log data then there is the HisRead Op.

Have a look at the documentation and let me know if doesn't make sense.