Create new ApprovalItem - error response : malformed or incorrect

[raclettierer]

Describe the bug

I submit a new approvalitem. The api response that the message are malformed or incorrect.

The body of the request looks like following json. The problem is that there is an additional odata type information.

{
    "allowEmailNotification": true,
    "approvalType": "basic",
    "approvers": [
        {
            "@odata.type": "#microsoft.graph.approvalIdentitySet",
            "user": {
                "displayName": "Alex Wilber",
                "id": "9a033c37-4b75-4a89-87f6-8cd7f5b66026"
            }
        }
    ],
    "description": "Details",
    "displayName": "Title of approval 22"
}

Expected behavior

Ignore the odata type by converting the object to a json string
"@odata.type": "#microsoft.graph.approvalIdentitySet",

How to reproduce

var requestBody = new ApprovalItem
  {
      DisplayName = "Title of approval 22",
      Description = "Details",
      ApprovalType = ApprovalItemType.Basic,
      AllowEmailNotification = true,
      AllowCancel = true,                        
      Approvers = new List<ApprovalIdentitySet>
      {
          new ()
          {
              User = new Identity
              {
                  Id = "9a033c37-4b75-4a89-87f6-8cd7f5b66026",
                  DisplayName= "Alex Wilber"
              },
          }
      }
  };
  var result = await graphBetaClient.Solutions.Approval.ApprovalItems.PostAsync(requestBody)

SDK Version

5.86.0

Latest version known to work for scenario above?

No response

Known Workarounds

Debug output

Click to expand log

```

</details>


### Configuration

_No response_

### Other information

_No response_

[andrueastman]

Transferring to the beta repo as this beta SDK related

[andrueastman]

Thanks for raising this @raclettierer

This looks to probably be a metadata/conversion side issue as the constructor initializes a value for the same here.

msgraph-beta-sdk-dotnet/src/Microsoft.Graph/Generated/Models/ApprovalIdentitySet.cs

Line 36 in 756ff7a

OdataType = "#microsoft.graph.approvalIdentitySet";

In the meantime, you could probably work around this by doing the following.

SerializationWriterFactoryRegistry.DefaultInstance.ContentTypeAssociatedFactories["application/json"] = new JsonSerializationWriterFactory(); // don't serialize null values
var requestBody = new ApprovalItem
{
    DisplayName = "Title of approval 22",
    Description = "Details",
    ApprovalType = ApprovalItemType.Basic,
    AllowEmailNotification = true,
    AllowCancel = true,
    Approvers = new List<ApprovalIdentitySet>
  {
      new ()
      {
          OdataType = null, // set value to null so that its ingored.
          User = new Identity
          {
              Id = "9a033c37-4b75-4a89-87f6-8cd7f5b66026",
              DisplayName= "Alex Wilber"
          },
      }
  }
};

[raclettierer]

@andrueastman I try your workaround, but the result is not as expected :-)

"approvers":[{
"@odata.type":null,
"@odata.type":null,
"user":{

Do you have any other ideas ?