Add validation of viz objects

[klisiecka-splunk]

Adding validation for dashboards, dashboard groups and charts: terraform provider should fail on plan if the payload is faulty.

[github-actions]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.87%. Comparing base (338a555) to head (5b3f063).
Report is 2 commits behind head on main.

Additional details and impacted files

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##             main     #554   +/-   ##
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  Coverage   94.87%   94.87%           
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  Files          35       35           
  Lines        2107     2107           
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  Hits         1999     1999           
  Misses         89       89           
  Partials       19       19           

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[MovieStoreGuy]

Please ensure that test are also included with changes. This is important to ensure behaviour is kept between versions and error cases are correctly handled.

[MovieStoreGuy]

Suggested change

	func dashboardValidate(ctx context.Context, dashboardObject *schema.ResourceDiff, config interface{}) error {
	func dashboardValidate(ctx context.Context, dashboardObject *schema.ResourceDiff, config any) error {

[MovieStoreGuy]

I would prefer to not add an interface within the utility file here, it will make it hard to maintain since it is somewhat hidden within the file of all the things that don't exactly fit within a resource object.

To be clear, the interface is fine but move it to a seperate file to make it easier to maintain and discover later on.

Moreover, Go doc style should take the form of:

// <Definition> ...
<Definition>

Please update to be reflect the go doc style.

[MovieStoreGuy]

One thing to be conscious of is that if the type isn't the expected value, this code will panic, not expecting that it will but if it were to, it is a terrible user experience.

I would suggest looking at type checking here.

[MovieStoreGuy]

I wonder if it is more worthwhile to abstract this further instead of passing in placed type params.

Something like:

type ChartValidatorFunc func(input) (ChartRequest, error)

func (fn ChartValidatorFunc) Validate(ctx, resource, config) error {
  if fn == nil {
   return errors.New("no data parser provided")
  }
  payload, err := fn(resource)
  if err != nil {
    return err
  }
  return config.ValidateChart(ctx, payload)
}

This is something that the standard lib does with http.HandlerFunc as a more concrete example.

[klisiecka-splunk]

I've added tests and implemented the suggested changes. Please let me know if there are any areas that need further improvement.

[MovieStoreGuy]

Please make sure you sign the CLA.

[klisiecka-splunk]

I have read the CLA Document and I hereby sign the CLA