#20700 Allow plugin authors to attach custom fields to `TargetData` for `pants peek` Issue created by ndellosa95 Is your feature request related to a problem? Please describe. We use

pants peek

to print metadata about that feeds into different processes in our CI. It seems silly to create a custom command to do basically the same thing when

peek

is already there. You can sort of already do this with custom target types if you use a

TargetGenerator

, but not with

TargetFilesGenerator

. Describe the solution you'd like Create a new union-type

TargetDataAdditionalInfoFieldSet

and an abstract

TargetDataAdditionalInfo

frozen dataclass with a

ClassVar[str]

attribute

label

. Add an attribute of type

Tuple[TargetDataAdditionalInfo, ...]

to TargetData in a field called

additional_info

. Plugin authors can provide union rules to return custom

TargetDataAdditionalInfo

class instances for additional info. The output will be formatted as such:

{
    ...
    "additional_info": {
        "label1": ...
        "label2": ...
    }
    ...
}

pantsbuild/pants