grafana dashboard broken for SLOs with dots in the name

[problame]

Problem

One of our SLOs has the name xyz-latency-10ms-99.99%.

The Grafana Dashboard linked from the README.md is broken for such SLOs.

Specifically, it sends queries like this

sloth_slo_info{sloth_service="pageserver", sloth_slo="xxx-latency-10ms-99\\.99%"}

because the underlying query (quoting from the dashboard JSON, hence double-escaping)

          "expr": "sloth_slo_info{sloth_service=\"${service}\", sloth_slo=\"${slo}\"}",

Root-Cause

Before queries are sent to your data source the query is interpolated, meaning the variable is replaced with its current value. During interpolation, the variable value might be escaped in order to conform to the syntax of the query language and where it is used. For example, a variable used in a regex expression in an InfluxDB or Prometheus query will be regex escaped. Read the data source specific documentation topic for details on value escaping during interpolation.

https://grafana.com/docs/grafana/latest/dashboards/variables/variable-syntax/

Solution

Use the regex label filter =~ instead of a plain =.

          "expr": "sloth_slo_info{sloth_service=~\"${service}\", sloth_slo=~\"${slo}\"}",

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I have done the work already to fix the dashboard JSON, we're using it internally.

I don't know what the process is to make a PR for the dashboard.

IMO it would be good if the JSON is versioned in this repository, instead of just being on Grafana.