Grafana global variables not interpolated in alerts

[brycefisher]

Queries used in alerts don't have any macros or variables expanded. This makes it very challenging to reuse panels for alerts.

Here's an example error (whitespace added) from a query that has a dashboard variable called $BusinessUnit:

Semantic error:
'MyTable
| where timestamp >= datetime(2020-10-22T18:23:46.551Z) and timestamp <= datetime(2020-10-22T18:28:46.551Z) 
    and business_unit == \"$BusinessUnit\"
| summarize count() by bin(timestamp, $__interval)
| order by timestamp asc'
has the following semantic error: 
  SEM0100: 'summarize' operator: 
    Failed to resolve scalar expression named '$__interval'.

Notice that neither $__interval nor $BusinessUnit was expanded in the query the alert generated.

Here's the same panel rendered as a line chart:

[marefr]

Template variables support, like business unit example, are limited by grafana/grafana#6557.

The $__interval one though can be supported if implemented in this data source.

[brycefisher]

@marefr thanks for the info! It would be great to support the $__interval and other time macros given the blocker from grafana/grafana#6557

[sunker]

Seems like $__interval support is already implemented.