[pkg/ottl] IsMatch works on maps and slices in contradiction to documentation

[swiatekm]

Component(s)

pkg/ottl

What happened?

Description

According to documentation IsMatch should return false for non-atomic types:

The function matches the target against the pattern, returning true if the match is successful and false otherwise. If target is a boolean, int, or float it will be converted to a string. If target is nil or not a string, boolean, int, or float false is always returned.

In reality, it serializes maps and slices to a string using JSON: https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/pkg/ottl/ottlfuncs/func_is_match.go#L56

Both the documentation and the code were added in the same PR (#16503) so I'm not sure what is actually intended, but the documented behavior makes more sense to me.

Collector version

v0.73.0

Environment information

No response

OpenTelemetry Collector configuration

No response

Log output

No response

Additional context

What I'm actually trying to do is detect if a value is a map, so if there's a simpler way of doing that, I'd appreciate some guidance.

[github-actions]

Pinging code owners:

• pkg/ottl: @TylerHelmuth @kentquirk @bogdandrutu @evan-bradley

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[TylerHelmuth]

@swiatekm-sumo thanks for finding this discrepancy. With the new concept of typed-getters I think this lets itself to using a StringLikeGetter in the future, so I would opt for the code being accurate and the documentation being inaccurate. If we are willing to convert 1 data type to a string it seems reasonable to convert any supported datatype to a string.

[swiatekm]

Allright, let's just update the documentation then.