[influxdb] How to use Kapacitor's regexReplace function

[teedilo]

I'm looking for advice on using Kapacitor's regexReplace function. All I'm
trying to do is replace slashes in the path for a disk alert with
underscores or some other character, as Sensu doesn't like slashes in Sensu
alert names. I can't figure out a simple use case like this from the
example in the documentation. This is my current admittedly lame attempt:

var data = stream
|from()
.measurement('disk')
.groupBy('host', 'path')
|eval(lambda: regexReplace("[/]", "path", "_"))
.as('pathsub')

I'm getting this message in the kapacitor.log file:

E! no field or tag exists for [/]

I'm assuming it's complaining about the "[/]" as the first parameter of the
regexReplace function. I thought this would work, however, because the
documentation links out to the Go language's ReplaceAllString function, and
I managed to get this concoction working in the interactive Go interpreter:

re2 := regexp.MustCompile("[/]")
fmt.Println(re2.ReplaceAllString("/this/is/a/path", "_"))
fmt.Println(re2.ReplaceAllString("/", "_"))

It seems that Kapacitor's regexReplace function is called differently from
Go's ReplaceAllString function, however, so I'm not terribly surprised that
my attempt to use this function in Kapacitor isn't working.

By the way, I tried using the regular expression /\// in Go's interpreter,
but I couldn't get that or any other concoction to work, which is why I
settled on "[/]".

Anyone spot anything obvious that I'm doing wrong? The example in the
Kapacitor documentation uses a capture string, but I can't see how that
applies here. I'm just trying to do simple character replacement, so this
shouldn't be as difficult as it seems to be.

Thanks.

[teedilo]

I've switched to trying to use the strReplace function, because that seems
to be a better fit for what I'm trying to do. I'm still having many
problems with the script, but I'm trying to work through those before I ask
more questions.