Support field selection with complex keys

[jahredhope]

When passing in columns, I'd like to be able to select data from an object when the keys in that object include full-stops.

For example, here is an entity from a KRM with 'annotations':

{ entity: { metadata: { annotations: { "example.com/custom-1": "foo"}}}

in this case I might want to try using a field attribute of entity.metadata.annotations["example.com/custom-1"].

This syntax works for numbers (e.g. a[1]), and KIND OF works for strings, as long as it doesn't contain full-stops.

This appears to come down to an implementation for 'byString' which first converts array syntax (a['key']) to object notation (a.key) before processing here:

core/src/utils/index.js

Line 7 in 0899171

s = s.replace(/\[(\w+)\]/g, '.$1'); // convert indexes to properties

Background

I'm using a data Table through another tool, specifically Backstage. And Kubernetes Resource Models (KRM) is the standard notation for defining entities. This leads to objects like in the above example.

Suggested solution

I think there are two solutions, either:

1. make field work for strings with array syntax with full-stops in keys
2. allow an array to be passed in, that explicitly declares the keys

Whilst the first option is possible it has the potential to change behaviour for existing consumers (not that I can think of a scenario where a consumer would want the current behaviour if they have a key with a full-stop).

So I'd suggest (and have a PR ready) to implement the latter. But also happy to see this added in any way, and if not I've found a hack solution to work around (by passing in an object with an overloaded 'split' method).

Thanks

Thank-you for considering this issue. I'll follow up with a PR shortly.

[matthewoestreich]

Closing per the PR that you submitted. Thank you so very much for your assistance!!