Security Center DataExportSettingProperties not unmarshalled properly

[beandrad]

Bug Report

• import path of package in question: github.com/Azure/azure-sdk-for-go/services/preview/security/mgmt/v3.0/security
• SDK version: 46.4.0
  • Commit: e3b3fa3

• What happened?
  Setting is returned by the Get function and it cannot be cast to DataExportSettingProperties since this returns an error or by calling AsDataExportSettings() since this returns nil.

Regarding the Azure API specs, Settinghttps://github.com/Azure/azure-rest-api-specs/blob/27cc07ddd294d98e05cb301e07a72378df9f87e8/specification/security/resource-manager/Microsoft.Security/stable/2019-01-01/settings.json#L175 is of type SettingResource has a field (kind) defined as discriminator, which makes SettingResource polymorphic.

• What did you expect or want to happen?
  I'd expect to be able to Get to DataExportSettings when the kind field in the Get response is DataExportSettings .

• Related issue: Add Enabled to ASC setting resource #12687

[ghost]

Thanks for the feedback! We are routing this to the appropriate team for follow-up. cc @chlahav.

[ArcturusZhang]

HI @beandrad thanks for this issue!

Yeah, now I see this API is problematic, if the resource itself is polymorphic, the returned model should have a discriminator. But in this case, the returned model Setting does not have a discriminator, but it directly inherit from SettingResource which has a discriminator and does not introduce more fields. This makes Settings and SettingResource effectively equivalent, but in this way the code generator is not able to detect that discriminator and gives us the wrong code.

I will possibly have a look at this issue in detail. But I assume to actually fix this, we will have to fix the problematic swagger definition to remove that redundant inheritances.

[ArcturusZhang]

I just had a quick test, the returned JSON from the service is

{"id":"/subscriptions/REDACTED/providers/Microsoft.Security/settings/MCAS","name":"MCAS","type":"Microsoft.Security/settings","kind":"DataExportSettings","properties":{"enabled":true}}

As you can see, this is clearly a DataExportSettings struct, but due to the reasons I explained above, we cannot actually cast this struct (its type is Settings) to DataExportSettings.

And unfortunately we do not have any workaround within the framework of the SDK. I will try to fix this by fixing the swagger, please stay tuned.

[ArcturusZhang]

Hi @beandrad I made some experiments refining the inheritance structure in the swaggers and generating new SDK, the following test code:

	client := security.NewSettingsClient(subsID, "westus2")
	client.Authorizer = authorizer
	resp, err := client.Get(ctx, "MCAS")
	if err != nil {
		return err
	}
	fmt.Println(reflect.TypeOf(resp.Value))

And it gives you this as expected:

security.DataExportSettings

Since we already have an upstream issue tracking this, I will then close this issue. Please stay tuned and I will release a new version as soon as the swagger is fixed. Thanks!

[ArcturusZhang]

Well, I decide to reopen this and close this from the new release PR.

[beandrad]

Thanks for looking into it @ArcturusZhang! :)