apply=groupby with aggregate does not return @odata.context

[oleg-ua]

before asking, i've read this issue: OData/WebApi#1712

performing the request http://localhost/tf/dataapi/workspaces
returns
{
"@odata.context": "http://localhost/tf/dataapi/$metadata#Workspaces",
"value": [
{
"Label": "W 638271950392162608",
"Code": "W 638271950392162608",
"IsActive": true,
"Description": "Generated by Watin test",
"IsHidden": false,
"CreatedOn": "2023-08-09T16:23:59+03:00",
"LastModifiedOn": "2023-08-09T16:23:59+03:00",
"Id": 116
},
...
}

but performing the request
http://localhost/tf/dataapi/workspaces?apply=groupby((IsActive),aggregate($count as Total))
returns
[
{
"IsActive": true,
"Total": 309
},
{
"IsActive": false,
"Total": 1
}
]

so, in the second request @odata.context is missing and thus the structure of the response is different - only value is returned.

The controller method looks like this:
` [EnableQueryTopSkipFilter(AllowedQueryOptions = Select | Expand | Top | OrderBy | Count | Skip | Filter | Apply)]
[SwaggerResponse(Status200OK, "Objects successfully retrieved.", typeof(IEnumerable))]
public virtual async Task<ActionResult<IQueryable>> Get(ODataQueryOptions odataQueryOptions)
{
return await TryCatchAsync(async () =>
{
PagedCollectResult entities = await Entities.Get(odataQueryOptions);

        return Page(entities, odataQueryOptions);
    });
}`

the Page Method:
` protected OkObjectResult Page(PagedCollectResult paginatedQueryResult, ODataQueryOptions odataQueryOptions)
{
IReadOnlyList entities = paginatedQueryResult.Result;

    if (odataQueryOptions.SetTotalCount())
    {
        // Bug: We need this line because to some internal AspNtCore.OData stuff. Just adding TotalCount number to PageResult doesn't work.
        Request.ODataFeature().TotalCountFunc = () => paginatedQueryResult.TotalNumberOfEntities;
    }

    Request.ODataFeature().NextLink = entities?.Count > 0
        ? Request.GetNextPageLink(paginatedQueryResult.TotalNumberOfEntities)
        : null;

    PageResult<TDataApiEntity> value = new(entities?.AsQueryable() ?? Enumerable.Empty<TDataApiEntity>().AsQueryable(),
        Request.ODataFeature().NextLink,
        odataQueryOptions.SetTotalCount() ? Request.ODataFeature().TotalCount.GetValueOrDefault() : null);

    return Ok(value);
}`

So, return type of the Get method is ActionResult<...>, but not IQueryable<...>. I saw in exampleas, that @odata.context is returned in case when controller returns IQueriable<...>.
Is it possible to return odata.context in my case as well?
Or maybe you can suggest what I should modify in the EDM model?

[peterkovecses]

I had the same issue, I solved it like this:
https://github.com/peterkovecses/ODataApplyDemo

[valentasm1]

Couple solutions are provided here
#181