[Feature Request] Array Data Types

[bestickley]

Description

Hi, could you consider supporting array data types?

Motivation

I specifically want to pass Amazon OpenSeach Domain Security Group IDs - so array of strings. Many more use cases though.

Proposed Solution

@type=array(string())

Alternatives

JSON.parse() string env var, not ideal.

Additional Information

No response

[theoephraim]

Definitely has been on the todo list for a while!

This could work # @type=array(string(startsWith=abc), minLength=2)
Or this: # @type=string(startsWith=abc) @arrayType(minLength=2)

Probably want to make it real easy to support splitting so an env var override could pass in a,b,c and you get an array.

Theres a question of how we set the stringified env var (join with commas versus more explicit JS style syntax)

We also probably might want to extend env-spec syntax to support explicit arrays ITEM=[a, b, c]
Currently we use () and do a weird hybrid key/val and array arg thing, and it's only supported as fn call args.
So this would be supported today ITEM=array(a, b, c)

open to input!

[bestickley]

Honestly whatever you think is best. I think I prefer # @type=string(startsWith=abc) @arrayType(minLength=2) so it's more explicit it is array type.

Ah, makes sense how you already need something like this for fn args. explicit arrays is best, but if reusing fn arg functionality is easier, I think it'd be fine. Thanks for sharing!

[theoephraim]

Yeah I think a separate @array decorator should be a bit easier to implement too. Currently the type stuff is slightly different than the rest of the function/args processing since each type is not actually a function, but they take args like they are. Wrapping them in array() with more args will make it a bit of a pain.

While its a bit unusual, the unified key/val and array fn args as been pretty useful to keep things super concise for the default case. Ex: fn(arg1, arg2, optionalThing=foo) the functions then just get both an arrayArgs and objectArgs passed to them. Get best of both worlds without any additional brackets :) But no reason to not also support explicit array brackets, especially for this case.