Range operator position is too strict

[davkal]

I'd like to write queries like

count_over_time({job="cortex-ops/ingester"}[5m] |= "error" )

which produces a syntax error: syntax error: unexpected |=, expecting ) Instead I have to write them like

count_over_time({job="cortex-ops/ingester"} |= "error" [5m])

[cyriltovena]

This is actually tricky because the engine is calling {job="cortex-ops/ingester"} |= "error" a log expression.

Not sure how we could refactor our yacc file.

@codesome you looked at this already what do you think ?

This is happening here:

https://github.com/grafana/loki/blob/master/pkg/logql/expr.y#L69

[codesome]

Looking at the above examples, {job="cortex-ops/ingester"}[5m] looks more like a range selector (and better), {job="cortex-ops/ingester"} |= "error" [5m] looks like a selector on a query.

I guess we cannot (or don't want to) get rid of the current approach as it will be a breaking change. I will take a look at the yacc file to see how it can be done, should be possible.

[codesome]

Got a way to do it, will open a PR tomorrow

[cyriltovena]

This is more a syntax sugar, I’m not sure we want to advertise it too much, what’s the rationale @davkal ?

[roidelapluie]

Because it feels more natural for Prometheus users