How to add my functionality before and after pagination, filtering, sorting and projection?

[vvitkovsky]

Hello, HotChocolate experts. I kindly need some help with this issue:

[UsePaging]
[UseProjection]
[UseSorting]
[UseFiltering]
[UseMyCache]
public IQueryable<Person> GetPersons([Service] PersonContext aContext)
{
     return aContext.Persons.AsQueryable();
}

The question is - how to add my own logic before the query (caching) and after the query (cache update)?
I tried to build my own middleware, but the problem is that I can't get into a state where the filtering, paging, and projection are already applied. Example of my middleware:

public class MyCacheMiddleware
{
    private readonly FieldDelegate _next;

    public MyCacheMiddleware(FieldDelegate next)
    {
        _next = next;
    }

    public async Task InvokeAsync(IMiddlewareContext context)
    {
        var cacheKey = GenerateCacheKey(context);

        await _next(context);

        if (context.Result is IQueryable<Person> queryable)
        {
            var result = await queryable.ToListAsync();
            // queryable.ToListAsync() returns all records from the database, no filtering, paging, sorting, etc.
        }
    }

    private string GenerateCacheKey(IMiddlewareContext context)
    {
        return $"{context.Selection.SyntaxNode}";
    }
}

I want to add my own caching before processing the request (that can be done with the mentioned middleware), but how can I update my cache with the final result after filtering, paging, sorting, etc.?

Best regards,
Victor

[vvitkovsky]

I have found one approach. Is this the correct one:

[UseMyCache]
[UsePaging]
[UseProjection]
[UseSorting]
[UseFiltering]    
public IQueryable<Person> GetPersons([Service] PersonContext aContext)
{
     return aContext.Persons.AsQueryable();
}

public class UseMyCacheAttribute : ObjectFieldDescriptorAttribute
{
    public UseMyCacheAttribute([CallerLineNumber] int order = 0)
    {
        Order = order;
    }

    protected override void OnConfigure(IDescriptorContext context, IObjectFieldDescriptor descriptor, MemberInfo member)
    {
        descriptor.Use<MyCacheMiddleware>();
    }
}

public class MyCacheMiddleware
{
    private readonly FieldDelegate _next;

    public MyCacheMiddleware(FieldDelegate next)
    {
        _next = next;
    }

    public async Task InvokeAsync(IMiddlewareContext context)
    {
        var cacheKey = GenerateCacheKey(context);

        await _next(context);

        if (context.Result is Connection<Person> queryable)
        {
            var result = queryable.Edges.Select(edge => edge.Node).ToList();
        }
    }

    private string GenerateCacheKey(IMiddlewareContext context)
    {
        return $"{context.Selection.SyntaxNode}";
    }
}

[davidfowl]

This isn’t really an aspire question you’ll have more luck asking on the hot chocolate repository