Bug affecting $apply/aggregate when using average aggregation method against floats and nullable floats

[gathogojr]

It appears there might an ODL bug affecting $apply/aggregate expression specifically when using average aggregation method against floats and nullable floats

Assemblies affected

• Microsoft.OData.Core 7.6.4
• Microsoft.AspNetCore.OData 7.4.1

Reproduce steps

1. Create an OData Web API project
2. Create a CLR type with float and nullable float properties

   public class Number
   {
       public int Id { get; set; }
       public float SingleProp { get; set; }
       public float? NullableSingleProp { get; set; }
   }

3. Create a controller with a Get action

   public class NumbersController : ODataController
   {
       // ...
       [EnableQuery]
       public IQueryable<Number> Get()
       {
           return _db.Numbers;
       }
       // ...
   }

4. Bootstrap the service

   // ...
   ODataModelBuilder modelBuilder = new ODataConventionModelBuilder();
   modelBuilder.EntitySet<Number>("Numbers");
   
   app.UseMvc(routeBuilder =>
   {
       routeBuilder.Select().Filter().Expand().Count().OrderBy().SkipToken().MaxTop(null);
       routeBuilder.MapODataServiceRoute("odata", "odata", modelBuilder.GetEdmModel());
   });
   // ...

5. Try to query for averages for the float and nullable float properties using $apply/aggregate expression
   a. http://ServiceRoot/Numbers?$apply=aggregate(SingleProp with average as AverageSingleProp)
   b. http://ServiceRoot/Numbers?$apply=aggregate(NullableSingleProp with average as AverageNullableSingleProp)

Expected result

The averages values for both properties should be returned in the respective cases

Actual result

An exception it thrown

{
"error": {
"code": "",
"message": "The query specified in the URI is not valid. $apply/aggregate expression 'Microsoft.OData.UriParser.SingleValuePropertyAccessNode' operation does not support value type 'Single'.",
"details": [],
"innererror": {
"message": "$apply/aggregate expression 'Microsoft.OData.UriParser.SingleValuePropertyAccessNode' operation does not support value type 'Single'.",
"type": "Microsoft.OData.ODataException",
"stacktrace": " at Microsoft.OData.UriParser.Aggregation.ApplyBinder.CreateAggregateExpressionTypeReference(SingleValueNode expression, AggregationMethodDefinition method)\r\n at Microsoft.OData.UriParser.Aggregation.ApplyBinder.BindAggregateExpressionToken(AggregateTokenBase aggregateToken)\r\n at Microsoft.OData.UriParser.Aggregation.ApplyBinder.BindAggregateToken(AggregateToken token)\r\n at Microsoft.OData.UriParser.Aggregation.ApplyBinder.BindApply(IEnumerable1 tokens)\r\n at Microsoft.OData.UriParser.ODataQueryOptionParser.ParseApplyImplementation(String apply, ODataUriParserConfiguration configuration, ODataPathInfo odataPathInfo)\r\n at Microsoft.OData.UriParser.ODataQueryOptionParser.ParseApply()\r\n at Microsoft.AspNet.OData.Query.ApplyQueryOption.get_ApplyClause() in C:\\Users\\jogathog\\Projects\\WebApi\\src\\Microsoft.AspNet.OData.Shared\\Query\\ApplyQueryOption.cs:line 78\r\n at Microsoft.AspNet.OData.Query.Validators.ODataQueryValidator.Validate(ODataQueryOptions options, ODataValidationSettings validationSettings) in C:\\Users\\jogathog\\Projects\\WebApi\\src\\Microsoft.AspNet.OData.Shared\\Query\\Validators\\ODataQueryValidator.cs:line 35\r\n at Microsoft.AspNet.OData.Query.ODataQueryOptions.Validate(ODataValidationSettings validationSettings) in C:\\Users\\jogathog\\Projects\\WebApi\\src\\Microsoft.AspNet.OData.Shared\\Query\\ODataQueryOptions.cs:line 586\r\n at Microsoft.AspNet.OData.EnableQueryAttribute.ValidateQuery(HttpRequest request, ODataQueryOptions queryOptions) in C:\\Users\\jogathog\\Projects\\WebApi\\src\\Microsoft.AspNetCore.OData\\EnableQueryAttribute.cs:line 222\r\n at Microsoft.AspNet.OData.EnableQueryAttribute.CreateAndValidateQueryOptions(HttpRequest request, ODataQueryContext queryContext) in C:\\Users\\jogathog\\Projects\\WebApi\\src\\Microsoft.AspNetCore.OData\\EnableQueryAttribute.cs:line 129\r\n at Microsoft.AspNet.OData.EnableQueryAttribute.<>c__DisplayClass1_0.<OnActionExecuted>b__1(ODataQueryContext queryContext) in C:\\Users\\jogathog\\Projects\\WebApi\\src\\Microsoft.AspNetCore.OData\\EnableQueryAttribute.cs:line 107\r\n at Microsoft.AspNet.OData.EnableQueryAttribute.ExecuteQuery(Object responseValue, IQueryable singleResultCollection, IWebApiActionDescriptor actionDescriptor, Func2 modelFunction, IWebApiRequestMessage request, Func2 createQueryOptionFunction) in C:\\Users\\jogathog\\Projects\\WebApi\\src\\Microsoft.AspNet.OData.Shared\\EnableQueryAttribute.cs:line 596\r\n at Microsoft.AspNet.OData.EnableQueryAttribute.OnActionExecuted(Object responseValue, IQueryable singleResultCollection, IWebApiActionDescriptor actionDescriptor, IWebApiRequestMessage request, Func2 modelFunction, Func2 createQueryOptionFunction, Action1 createResponseAction, Action`3 createErrorAction) in C:\Users\jogathog\Projects\WebApi\src\Microsoft.AspNet.OData.Shared\EnableQueryAttribute.cs:line 415"
}
}
}

Additional detail

This is almost certainly a bug since $apply/aggregate works for sum, min and max aggregation method

• http://ServiceRoot/Numbers?$apply=aggregate(SingleProp with sum as SumSingleProp)

• http://ServiceRoot/Numbers?$apply=aggregate(NullableSingleProp with sum as SumNullableSingleProp)

• http://ServiceRoot/Numbers?$apply=aggregate(SingleProp with min as MinSingleProp)

• http://ServiceRoot/Numbers?$apply=aggregate(NullableSingleProp with min as MinNullableSingleProp)

• http://ServiceRoot/Numbers?$apply=aggregate(SingleProp with max as MaxSingleProp)

• http://ServiceRoot/Numbers?$apply=aggregate(NullableSingleProp with max as MaxNullableSingleProp)