sciensoft / hateoas Goto Github PK

To my knowledge, in current version it is not possible to add multiple policies when multiple routes return the same DTO. Let's suppose we have a DTO that returns ID when some object was created; then if the same DTO with ID is used as a response in CreateUser, CreateTeam, CreateBook, etc., all links defined within the policy will be visible everytime.

The solution: maybe an option to specify route name in policy or somehow build policies around controller method with help of expressions - not just around models?

It would be cool if link generation supports custom response objects.

Example:

        {
            "data": [
                {
                    "firstName": "Jhon",
                    "lastName": "Doe",
                    "links": [
                        {
                            "method": "GET",
                            "uri": "https://localhost:5001/api/person/5",
                            "relation": "Self",
                            "message": "Self link"
                        }
                    ]
                }
            ],
            "statusCode": 200,
            "message": "success"
        }

Is it possible (if yes how?) to add links to collections (lists, arrays, IEnumerable) like in Tapioca.HATEOAS? Could you prepare a sample code?

In my oppinion LinkExtension.AddLink does not have enough flexibility. It is not possible to set custom JSON serializer options, use other methods instead of AddMvcCore like AddControllers. This may lead to braking the existing code.

The solution could be to extract parts of LinkExtension.AddLink e.g.

services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
services.AddTransient<HateoasUriProvider<InMemoryPolicyRepository.SelfPolicy>, HateoasSelfUriProvider>();
services.AddTransient<HateoasUriProvider<InMemoryPolicyRepository.RoutePolicy>, HateoasRouteUriProvider>();
services.AddTransient<HateoasUriProvider<InMemoryPolicyRepository.CustomPolicy>, HateoasCustomUriProvider>();
services.AddTransient<HateoasUriProvider<InMemoryPolicyRepository.ExternalPolicy>, HateoasExternalUriProvider>();

services.AddTransient<IHateoasResultProvider, HateoasResultProvider>();

so that they can be executed in user code without calling services.AddMvcCore implicitly in LinkExtension.AddLink.

Other solution may be making the classes public.

In the case of reverse proxies and API gateways. The client interacts with a URL different than the URL where the API is hosted. For example, consider if my API is hosted on a URL http://api.example.com/apiresources/ which is called downstream URL and clients are supposed to interact with the URL https://gateway-apiresources.example.com which is called upstream url. Then in the response clients are always getting downstream URLs but they are supposed to get upstream URL.

While I was able to update the domain and scheme part using ForwardedHeadersMiddleware I am still not able to remove the apiresources at the end of the URL. Is there any solution other than using AddExternalUri?

On .NET Core 3 (checked on 3.1.201), when Newtonsoft.Json serializer is used, returned DTO from controllers is wrong:

{
  "Id": {
    "valueKind": 3
  },
  "CreatedOn": {
    "valueKind": 3
  },
  "CreatedBy": {
    "valueKind": 3
  },
  "LastSavedOn": {
    "valueKind": 3
  },
  "LastSavedBy": {
    "valueKind": 3
  },
  "Latitude": {
    "valueKind": 4
  },
  "Longitude": {
    "valueKind": 4
  },
  "links": [
    {
      "method": "GET",
      "uri": "http://localhost:2138/api/station/get/2af61203-e39f-4998-0be3-08d7e6a9860f",
      "relation": "Self"
    },
    {
      "method": "DELETE",
      "uri": "http://localhost:2138/api/station/delete/2af61203-e39f-4998-0be3-08d7e6a9860f",
      "relation": "DeleteStation"
    }
  ]
}

After using default serializer in .NET Core 3, i.e., System.Text.Json the DTO is serialized correctly:

{
  "Id": "2af61203-e39f-4998-0be3-08d7e6a9860f",
  "CreatedOn": "2020-04-22T10:40:06.9052182",
  "CreatedBy": "b2ac5452-e45c-4ed3-4d76-08d7dfa3a155",
  "LastSavedOn": "2020-04-22T10:40:06.9052182",
  "LastSavedBy": "b2ac5452-e45c-4ed3-4d76-08d7dfa3a155",
  "Latitude": 0,
  "Longitude": 0,
  "links": [
    {
      "method": "GET",
      "uri": "http://localhost:2138/api/station/get/2af61203-e39f-4998-0be3-08d7e6a9860f",
      "relation": "Self"
    },
    {
      "method": "DELETE",
      "uri": "http://localhost:2138/api/station/delete/2af61203-e39f-4998-0be3-08d7e6a9860f",
      "relation": "DeleteStation"
    }
  ]
}

I've noticed that [JsonIgnore] attribute doesn't affect response when Sciensoft.Hateoas library is added to IServiceCollection.
I would like to decorate some properties with this attribute to skip serialization.
Alternate solution is to create new DTO without ignored property, but decorating one is much easier.