Operations Issues

I've been using operations mainly for creating multiple related entities, but I want to extend my usage so after updating to the latest pre-release I started testing the current functionality.

I've found the following issues:

1. Get: requesting a List-Relationship yields a NullReferenceException
2. Get: specifying a wrong type yields a NullReferenceException
3. Remove: the response is always an empty array - both in case of a success and if the entity doesn't actually exist.

[jaredcnance]

Thanks! I’ll look into these this weekend.

[jaredcnance]

@nikalfa sorry for the delay on this issue. The fixes are going to be released in v2.4.0-beta5 (see #357 for details). If everything goes well this is going to be the last beta release and we should roll a 2.4.0 sometime in the next week.

Regarding (3), I'm not certain what the best way to proceed on this is yet. Consider the case where I want to remove a resource before I perform some other operation in the same request. I may or may not actually care if that resource exists, I just want to ensure it does not exist before proceeding. So, I think it may be acceptable to process a remove operation and report success even if the resource did not exist. You could achieve an error response by first requesting the resource and then deleting it. While this results in 2 requests to the db in the existent case (albeit over the same connection), it would return a 404 in the non-existent case and the entire transaction will rollback.

However, this behavior does contradict the v1 behavior of returning a 404 in the case of DELETE requests. What do you think?

Reproduced Errors

Adding stack traces to the issue in case of regression.

1. Get: requesting a List-Relationship yields a NullReferenceException

JsonApiDotNetCore.Internal.JsonApiException: Transaction failed on operation[0] (get) for an unexpected reason. ---> System.NullReferenceException: Object reference not set to an instance of an object.
   at DocumentData JsonApiDotNetCore.Builders.DocumentBuilder.GetData(ContextEntity contextEntity, IIdentifiable entity, IResourceDefinition resourceDefinition) in /Users/jarednance/dev/json-api-dotnet-core/src/JsonApiDotNetCore/Builders/DocumentBuilder.cs:line 115
   at DocumentData JsonApiDotNetCore.Builders.DocumentBuilder.GetData(ContextEntity contextEntity, IIdentifiable entity) in /Users/jarednance/dev/json-api-dotnet-core/src/JsonApiDotNetCore/Builders/DocumentBuilder.cs:line 111
   at async Task<object> JsonApiDotNetCore.Services.Operations.Processors.GetOpProcessor<T, TId>.GetRelationshipAsync(Operation operation) in/Users/jarednance/dev/json-api-dotnet-core/src/JsonApiDotNetCore/Services/Operations/Processors/GetOpProcessor.cs:line 140
   at async Task<Operation> JsonApiDotNetCore.Services.Operations.Processors.GetOpProcessor<T, TId>.ProcessAsync(Operation operation) in /Users/jarednance/dev/json-api-dotnet-core/src/JsonApiDotNetCore/Services/Operations/Processors/GetOpProcessor.cs:line 85
   at async Task JsonApiDotNetCore.Services.Operations.OperationsProcessor.ProcessOperation(Operation op, List<Operation> outputOps) in /Users/jarednance/dev/json-api-dotnet-core/src/JsonApiDotNetCore/Services/Operations/OperationsProcessor.cs:line 74
   at async Task<List<Operation>> JsonApiDotNetCore.Services.Operations.OperationsProcessor.ProcessAsync(List<Operation> inputOps) in /Users/jarednance/dev/json-api-dotnet-core/src/JsonApiDotNetCore/Services/Operations/OperationsProcessor.cs:line 48
   --- End of inner exception stack trace ---
   at JsonApiDotNetCore.Services.Operations.OperationsProcessor.<ProcessAsync>d__4.MoveNext() in /Users/jarednance/dev/json-api-dotnet-core/src/JsonApiDotNetCore/Services/Operations/OperationsProcessor.cs:line 63
...

2. Get: specifying a wrong type yields a NullReferenceException

JsonApiDotNetCore.Internal.JsonApiException: Transaction failed on operation[0] (get) for an unexpected reason. ---> System.NullReferenceException: Object reference not set to an instance of an object.
   at IOpProcessor JsonApiDotNetCore.Services.Operations.OperationProcessorResolver.LocateGetService(Operation operation) in /Users/jarednance/dev/json-api-dotnet-core/src/JsonApiDotNetCore/Services/Operations/OperationProcessorResolver.cs:line 68
   at IOpProcessor JsonApiDotNetCore.Services.Operations.OperationsProcessor.GetOperationsProcessor(Operation op) in /Users/jarednance/dev/json-api-dotnet-core/src/JsonApiDotNetCore/Services/Operations/OperationsProcessor.cs:line 138
   at async Task JsonApiDotNetCore.Services.Operations.OperationsProcessor.ProcessOperation(Operation op, List<Operation> outputOps) in /Users/jarednance/dev/json-api-dotnet-core/src/JsonApiDotNetCore/Services/Operations/OperationsProcessor.cs:line 73
   at async Task<List<Operation>> JsonApiDotNetCore.Services.Operations.OperationsProcessor.ProcessAsync(List<Operation> inputOps) in /Users/jarednance/dev/json-api-dotnet-core/src/JsonApiDotNetCore/Services/Operations/OperationsProcessor.cs:line 48
   --- End of inner exception stack trace ---
   at JsonApiDotNetCore.Services.Operations.OperationsProcessor.<ProcessAsync>d__4.MoveNext() in /Users/jarednance/dev/json-api-dotnet-core/src/JsonApiDotNetCore/Services/Operations/OperationsProcessor.cs:line 63