Enhancement Request: Read-Only Service interface

[rpatrick00]

Description

I am trying to use the framework to access read-only data stored in Elasticsearch. Taking the recommended approach, I started customizing the service layer only to realize there were a dozen or so create, update, and delete interfaces I needed to implement that were irrelevant to my use case. I think it would be nice if the service layer interface had a read-only interface that I could extend.

[wisepotato]

you need to disable a few methods but this is certainly possible, can you give an example of these "dozens" of interfaces? We're open to these suggestions, as a readonly service is a great addition. @maurei thoughts?

[wisepotato]

Althought this isn't too much work to implement. Will investigate. we're currently working on a major refactor to decouple a singleton in the code, so this can either be solved during that time or after :)

[rpatrick00]

I’m not sure how to “disable” the methods. Simply throw a not implemented exception?

My object generally has no need for create, update, delete operations on the object or relationships. Also, we do not support GetAll without filters.

[wisepotato]

well a not implemented would server well, or a jsonapiexception would serve nice as you have control voer the status code

[maurei]

Hi @rpatrick00,

If I'm not mistaken, the interfaces you're looking for can be found here. Looks like you want to use the IResourceQueryService<T, TId> interface.

If you need custom service code, you can just use this to build your own implementation and register it

// implementation
public class ReadOnlyResourceService<T, TId> : IResourceQueryService<T, TId> { ... }

// registering
services.AddScoped<IResourceService<T, TId>, ReadOnlyResourceService<T, TId>>();

If you still want to use the boilerplate code from EntityResourceService<T,TId>: I believe you can simply inherit it and register it

// implementation
public class ReadOnlyResourceService<T, TId> : EntityResourceService<T, TId> { ... }

// registering
services.AddScoped<IResourceService<T, TId>, ReadOnlyResourceService<T, TId>>();

This way your implementation will still contain the the create, update, delete methods, but wherever your implementation is injected these methods will not be exposed, so you could choose not to worry about that.

Then there is a JsonApiQueryController that seems to be designed for read-only resources. I would have expected there to be a constructor that just takes the query service:

public JsonApiQueryController(
    IJsonApiContext jsonApiContext,
    IResourceQueryService<T, TId> resourceQueryService)  // <--- this is actually not here, it is IResourceService in the current implementation
: base(jsonApiContext, resourceService)
{ }

But interestingly enough, there is only the constructor that accept IResourceService, which exposes also the create/update/delete operations. I think we should add the constructor above. For completeness you could add the following workaround-base-controller for your readonly resources

    public class JsonApiQueryControllerFixed<T, TId>
            : BaseJsonApiController<T, TId> where T : class, IIdentifiable<TId>
    {
        public JsonApiReadOnlyController(
            IJsonApiContext jsonApiContext,
            IResourceQueryService<T, TId> resourceService)
        : base(jsonApiContext, resourceService)
        { }

        [HttpGet]
        public override async Task<IActionResult> GetAsync() => await base.GetAsync();

        [HttpGet("{id}")]
        public override async Task<IActionResult> GetAsync(TId id) => await base.GetAsync(id);

        [HttpGet("{id}/relationships/{relationshipName}")]
        public override async Task<IActionResult> GetRelationshipsAsync(TId id, string relationshipName)
            => await base.GetRelationshipsAsync(id, relationshipName);

        [HttpGet("{id}/{relationshipName}")]
        public override async Task<IActionResult> GetRelationshipAsync(TId id, string relationshipName)
            => await base.GetRelationshipAsync(id, relationshipName);
    }

so that you can have your controllers as follows

    public class YourResourceController : JsonApiQueryControllerFixed<YourResource, int>
    {
        public CompaniesController(
            IJsonApiContext jsonApiContext,
            IResourceQueryService<YourResource, int> queryService)
        : base(jsonApiContext, queryService)
        { }
    }

Let me know if this helps!

[rpatrick00]

@maurei, thanks! That's a huge help. I will give it a try.

[maurei]

closing as question resolved, created a new issue dedicated to the problem I mentioned in my earlier comment