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Value cannot be null for declaryingType when visting FieldInfo

See original GitHub issue

Hello all! I’m experiencing the following exception in my setup:

System.ArgumentNullException: Value cannot be null.
Parameter name: declaringType
   at HotChocolate.Validation.FieldSelectionMergingVisitor.FieldInfo..ctor(IType declaringType, FieldNode field)
   at HotChocolate.Validation.FieldSelectionMergingVisitor.VisitField(FieldNode field, IType type, ImmutableStack`1 path)
   at HotChocolate.Validation.QueryVisitor.VisitSelectionSet(SelectionSetNode selectionSet, IType type, ImmutableStack`1 path)
   at HotChocolate.Validation.QueryVisitor.VisitOperationDefinition(OperationDefinitionNode operation, ImmutableStack`1 path)
   at HotChocolate.Validation.FieldSelectionMergingVisitor.VisitDocument(DocumentNode document, ImmutableStack`1 path)
   at HotChocolate.Validation.QueryVisitorValidationErrorBase.Validate(ISchema schema, DocumentNode queryDocument)
   at HotChocolate.Validation.QueryValidator.Validate(DocumentNode query)
   at HotChocolate.Execution.QueryExecuter.CreateQueryInfo(String queryText)
   at HotChocolate.Runtime.Cache`1.GetOrCreate(String key, Func`1 create)
   at HotChocolate.Execution.QueryExecuter.ExecuteInternalAsync(QueryRequest request, CancellationToken cancellationToken)
   at HotChocolate.AspNetCore.QueryMiddlewareBase.HandleRequestAsync(HttpContext context, QueryExecuter queryExecuter)
   at HotChocolate.AspNetCore.QueryMiddlewareBase.InvokeAsync(HttpContext context)
   at Microsoft.AspNetCore.Routing.EndpointMiddleware.Invoke(HttpContext httpContext)
   at Microsoft.AspNetCore.Routing.EndpointRoutingMiddleware.Invoke(HttpContext httpContext)
   at Microsoft.AspNetCore.StaticFiles.StaticFileMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Cors.Infrastructure.CorsMiddleware.InvokeCore(HttpContext context)
   at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)

My startup:

services.AddGraphQL(serviceProvider => Schema.Create(options =>
{
    options.RegisterServiceProvider(serviceProvider);
    options.RegisterQueryType<ObjectType<GraphQLRepository>>();
    options.RegisterType<InputObjectType<MapDefinition>>();
}));

My types:

public class GraphQLRepository
{
    private DbContext dbc;

    public GraphQLRepository(DbContext dbContext)
    {
        dbc = dbContext;
        productMatcher = matcher;
    }

    // This works!
    public async Task<List<EntityFrameworkType>> EntityFrameworkType() => await dbc.EntityFrameworkType.ToListAsync();

    // This produces the declaringType cannot be null exception.
    public async Task<int> AddNewMap(MapDefinition mapDefinition)
    {
        return 1;
    }
}

public class MapDefinition
{
    public int Id { get; set; }
}

I think I’m missing a fundamental concept here…trying to figure it out through the docs and what not. I believe it has something to do with parsing the MapDefinition argument of AddNewMap. I’ve tried IType, and Object/InputObject inheritance wrappers. I’ve also enabled trace level logs in appSettings. Is there any way I can drill deeper?

Issue Analytics

  • State:closed
  • Created 5 years ago
  • Comments:13 (9 by maintainers)

github_iconTop GitHub Comments

1reaction
michaelstaibcommented, Dec 20, 2018

I have opened a new issue #411 for the nullrefexception… we will fix that with the next release. Although the query was invalid there should never be a nullrefexception from the system. Thanks for reporting that.

1reaction
michaelstaibcommented, Dec 19, 2018

Ok, I will have a look at it.

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