Send a Web Request From LabVIEW to Systemlink Server Using Get HTTP Method

In addition to SystemLink API available in LabVIEW, it is possible to control SystemLink server externally using  HTTP APIs. This document explains how to use the GET method in LabVIEW as an example of using the HTTP APIs.

1. Log in to SystemLink Web Application and from the Utility>>Tag menu, Create a new tag. 

 

2. Double-click the created tag, enter an appropriate value and Save it.

 

3. Click the question mark button ? on the upper right corner of Tag viewer,  and select HTTP API to access the Swaager UI's Tag Service domain.

 

4. To get the current value of a specifc tag, use the  GET/v2/tags/ {path}/values​​/current  HTTP API. 

5. Click Try it out
6. Enter the name of the tag you created earlier and click Execute to send the request.

7. A successfull request will return the code 200 and the tag value displayed in the Response body as below.

8. A similar request can be made from LabVIEW using GET VI as follow. 

 

9. Replace the OpenHandle VI's "admin" and "password" with the corresponding Username and password used to log into SystemLink Web Application.
10. The GET.vi input parameter is the Request URL from Responses operation in Swagger UI( check imagein step 7). Running this Programm in LabVIEW will return the same Responses as when executed in Swagger UI.