Fail loading an ACL config if the provided file is empty and enforceTableACLConfig is true

[garfthoffman]

Description

When the ACL file is loaded, add a check to verify that the config is not empty and fail execution if the --enforce-tableacl-config flag has been provided.

Related Issue(s)

closes #17273

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[arthurschreiber]

I'm not sure if this is the correct place to perform this validation. I think a config file containing an empty JSON object should be treated as "valid", but a truncated file seems like a pretty clear configuration mistake. 🤔

[garfthoffman]

Addressed in eca5d61

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 67.37%. Comparing base (0b51839) to head (d47a37b).
Report is 100 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #17274   +/-   ##
=======================================
  Coverage   67.37%   67.37%           
=======================================
  Files        1573     1573           
  Lines      253113   253116    +3     
=======================================
+ Hits       170538   170544    +6     
+ Misses      82575    82572    -3     

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[mattlord]

@garfthoffman did you want to move forward with this? If so, let's mark it ready for review and go from there. Thanks!

[arthurschreiber]

@mattlord Can you take another look?

[mattlord]

From the issue, the problem you're trying to solve seems to be more about whether or not the file contains a valid JSON document. Is that not correct? Unless I'm missing something, we should instead validate that the file contains a valid JSON document rather than just checking that it's empty (which would also be an invalid JSON doc as an empty doc would be "{}").

So instead of:

	if len(data) == 0 {
		return errors.New("tableACL config file is empty")
	}

It would be:

	if !json.Valid(data) {
		return errors.New("tableACL config file is invalid")
	}

I don't have a problem with the current code, but it doesn't seem like it resolves the issue as I read it.

[mattlord]

We should use require/assert in new tests. So e.g. here it would be:

err := f.Close()
require.NoError(t, err)

Or even just: require.NoError(t, f.Close())