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)

• Fixes: Bug Report: Empty/truncated file considered valid when enforceTableACLConfig is set #17273

Checklist

• "Backport to:" labels have been added if this change should be back-ported to release branches
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• Documentation was added or is not required

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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%           
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  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())

[mhamza15]

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.

I need to have another look as it's been a long time, but I believe the issue is that an empty file is treated as valid Protobuf, while an empty file is invalid JSON. So before it gets a chance to treat it as JSON, it's assumed to be a valid Protobuf file.

[mattlord]

I need to have another look as it's been a long time, but I believe the issue is that an empty file is treated as valid Protobuf, while an empty file is invalid JSON. So before it gets a chance to treat it as JSON, it's assumed to be a valid Protobuf file.

That's true, the file has to be in a valid prototext or json format that can be marshaled into the protobuf message and an empty value is fine in that context. But now that I look at the code in the PR again, we DO check for the file being empty along with validating the contents:

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

	config := &tableaclpb.Config{}
	if err := config.UnmarshalVT(data); err != nil {
		// try to parse tableacl as json file
		if jsonErr := json2.UnmarshalPB(data, config); jsonErr != nil {
			log.Infof("unable to parse tableACL config file as a protobuf or json file.  protobuf err: %v  json err: %v", err, jsonErr)
			return fmt.Errorf("unable to unmarshal Table ACL data: %s", data)
		}
	}

So I think that the PR is good as-is! 🙂 I was too hurried in my initial glance. I apologize about that. I'll approve now.

[mattlord]

LGTM! Note that we should still replace the usage of t.Fatal in the new test before we merge. But that's a very minor thing.

Thank you, @garfthoffman ! And I apologize for the delay. ❤️

[mattlord]

@garfthoffman you'll also need to merge in origin/main before we can pass the CI tests and then eventually merge the PR. Please let me know if you need any help with the minor test changes or anything else so that we can get this merged ASAP for you.