[files domain] support for multiple files with same name

[brandtkeller]

Is your feature request related to a problem? Please describe.

There is a defined use-case for needing to support multiple files with the same base name but located in different directories.

The current files domain documentation states:

The File domain specification accepts a descriptive name for the file as well as its path. The filenames and descriptive names must be unique.

I interpret this to mean that there is a constraint where two files with the same name with different paths is an un-supported workflow at this time.

Example:

domain:
  file-spec:
    filepaths:
    - name: fileone
      path: path/to/fileone/file.yaml
    - name: filetwo
      path: path/to/filetwo/file.yaml
  type: file

This would be encountered during specific examples of where naming-conventions for a given structure are dictated by discovery that relies upon filename.

Describe the solution you'd like

• Given multiple files with the same name on different paths
• When resources for the files are collected
• Then all required data is present

Describe alternatives you've considered

I would consider two solutions. An intermediate solution that resolves collision and makes collection available (this issue) - and a longer-term solution that provides support for a true cache or packaging mechanism when needing to collect the files for transfer with other resources.

Additional context

N/A

Expected Deliverable

Update to the files domain GetResources() logic to support matching filenames across different paths.

[brandtkeller]

@mildwonkey Can you check my understanding here?

[mildwonkey]

Correct, at the moment the actual filename is mapped to the user-supplied file.Name. It should be simple enough to swap the base name (it's using filepath.Base) out for the (original) abs path (before it's copied to the temp work dir):

https://github.com/defenseunicorns/lula/blob/main/src/pkg/domains/files/files.go#L76

[brandtkeller]

Looking at the logic and the preceding lines we would need to alter realdst in some way to help make the file copied to the temporary directory unique - as the example above would result it a collision during the copy if I am looking at that correctly.