Refresh Datasource on variable change

Grafana Plugin Development
1

Hi All,
i create a custom datasource and i’m using it for filling a Table (OOTB grafana table). For now it is working fine but i have to do an enhancement, the datasource should be filtered according to a variable so after the variable change the table should refresh with the new “filtered” content.
Unfortunately when i change the variable value there is no refresh (i should manually trigger a refresh).
How can i specify that my datasource could change response according a variable so if a variable change the data from datasource should be refresh?
Thank you so much.

2

Hello,

In your OnChange you can put a onRunQuery()

Nicolas

3

Hi Nicolas,
as far as i know onchange is called only in configuration. Am i right?
Regards

Carlo

4

Hmm, can you send me your query editor, im using a select so i have an onchange in this.

Nicolas

5

If you do replaceVariables inside the Data Source, it won’t trigger the update when the variable is refreshed.

The Query Editor for the Data Source variable should have a text input, which uses the variable, and then you can do replaceVariables from it.

6

My problem is no during the edit mode. When I have already configured a table with my custom datasource if user change the value of a variable i want to refresh the content of the table.

7

This is what I was saying, and it works for our data sources.

  1. Variable change will trigger Data source update.
  2. Data Source should use a Variable in the Input box to retrieve data.
  3. Data change in Data Source will trigger Table refresh.
8

Hi, I’m also struggling with this.

I have a custom backend datasource with the query editor etc.

I have a text field in the query editor, I have the ${myvar} as a value in that field, but when I change the dashboard variable myvar (text field variable), datasource is triggered, i.e. it runs the query against the backend process, but with the old value of the variable.

So I guess what I should ask - is there a hook I should subscribe to in order to refresh the result of templateSrv.replace(…) for the field value before the query is submitted to the backend process?