Loki Trigger Server Address doesn't support sub path

[pawan-regoti]

KEDA uses an community integration for LOKI based scaling: https://keda.sh/docs/2.19/scalers/loki/

Internally it tries to use these api endpoints to make query: https://grafana.com/docs/loki/latest/reference/loki-http-api/

But there is another issue inside the loki_scaler community code: https://github.com/kedacore/keda/blob/main/pkg/scalers/loki_scaler.go#L122
here, it overrides the existing url path with /loki/api/v1/query due to which the final url becomes http://<loki-host>:3100/loki/api/v1/query.
it only accepts serverAddress which has a base url like http://<loki-host>:3100, and not any url with sub-path.

If there is a extra sub path to the url,
for eg: http://<company-host>:3100/<product_name>/grafana,
instead of the url becoming http://<company-host>:3100/<product_name>/grafana/loki/api/v1/query,
it becomes http://<company-host>:3100/loki/api/v1/query, which is not correct in our case.

Need help with a workaround.

[pawan-regoti]

we can update the path as u.Path = u.Path + loki_path at https://github.com/kedacore/keda/blob/main/pkg/scalers/loki_scaler.go#L122

[rickbrouwer]

Continues via #7648