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Я следую примеру на https://github.com/graphql-dotnet/server чтобы создать GraphQL, но я получаю вышеуказанную ошибку (полная версия ниже) при переходе к моему http://localhost:5001/graphql .

Я поиграл со многими аспектами asp.core DependencyInjections, но все равно возвращается к этой ошибке:

     System.InvalidOperationException: Unable to resolve service for type 'MyProject.GraphQL.MySchema' while attempting to activate 'GraphQL.Server.Internal.DefaultGraphQLExecuter`1[MyProject.GraphQL.MySchema]'.
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateArgumentCallSites(Type serviceType, Type implementationType, CallSiteChain callSiteChain, ParameterInfo[] parameters, Boolean throwIfCallSiteNotFound)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateConstructorCallSite(ResultCache lifetime, Type serviceType, Type implementationType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateOpenGeneric(ServiceDescriptor descriptor, Type serviceType, CallSiteChain callSiteChain, Int32 slot, Boolean throwOnConstraintViolation)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateOpenGeneric(Type serviceType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateCallSite(Type serviceType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.<>c__DisplayClass7_0.<GetCallSite>b__0(Type type)
   at System.Collections.Concurrent.ConcurrentDictionary`2.GetOrAdd(TKey key, Func`2 valueFactory)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.GetCallSite(Type serviceType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.ServiceProviderEngine.CreateServiceAccessor(Type serviceType)
   at System.Collections.Concurrent.ConcurrentDictionary`2.GetOrAdd(TKey key, Func`2 valueFactory)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.ServiceProviderEngine.GetService(Type serviceType, ServiceProviderEngineScope serviceProviderEngineScope)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.ServiceProviderEngineScope.GetService(Type serviceType)
   at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService(IServiceProvider provider, Type serviceType)
   at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService[T](IServiceProvider provider)
   at GraphQL.Server.Transports.AspNetCore.GraphQLHttpMiddleware`1.InvokeAsync(HttpContext context) in /_/src/Transports.AspNetCore/GraphQLHttpMiddleware.cs:line 136
   at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)
  

Может кто-нибудь указать мне правильное направление, чтобы исправить это, пожалуйста
.Net Core 5.0;
Последняя версия Nuget GraphQL.Net Сервер

Мой код Startup.cs

 using GraphQL;
using GraphQL.Server;
using GraphQL.SystemTextJson;
using GraphQL.Types;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Serilog;

namespace Ace.Aceterilize
{
    public class Startup
    {
        public Startup(IConfiguration configuration, IWebHostEnvironment environment)
        {
            Configuration = configuration;
            Environment = environment;
        }

        public IConfiguration Configuration { get; }

        public IWebHostEnvironment Environment { get; }
        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddDbContext<MyDbContext>(options => options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")), ServiceLifetime.Singleton);

            services.AddHttpContextAccessor();
            //GraphQL
            services.AddSingleton<IDocumentExecuter, DocumentExecuter>();
            services.AddSingleton<IDocumentWriter, DocumentWriter>();

            services.AddSingleton<MyQuery>();
            services.AddSingleton<ISchema, MySchema>();

            services.AddGraphQL((options, provider) =>
        {
            options.EnableMetrics = Environment.IsDevelopment();
            var logger = provider.GetRequiredService<ILogger>();
            options.UnhandledExceptionDelegate = ctx => logger.Error("GraphQL: {Error} occurred", ctx.OriginalException.Message);
        })
         // Add required services for GraphQL request/response de/serialization
        .AddSystemTextJson(configureDeserializerSettings => { }, configureSerializerSettings => { })
        .AddErrorInfoProvider(opt => opt.ExposeExceptionStackTrace = Environment.IsDevelopment())
        .AddWebSockets() // Add required services for web socket support
        .AddDataLoader() // Add required services for DataLoader support
        .AddGraphTypes(typeof(AceteriliseSchema), ServiceLifetime.Transient);

            services.AddControllersWithViews();

        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
 //... Standard if development Mode
            }

            app.UseWebSockets();
            app.UseGraphQL<MySchema, GraphQLHttpMiddlewareWithLogs<MySchema>>();
            app.UseGraphQLWebSockets<MySchema>();
            // use graphiQL middleware at default path /ui/graphiql
            app.UseGraphiQLServer();

            // use graphql-playground middleware at default path /ui/playground
            app.UseGraphQLPlayground();

            // use altair middleware at default path /ui/altair
            app.UseGraphQLAltair();

            // use voyager middleware at default path /ui/voyager
            app.UseGraphQLVoyager();

          
        }
    }
}
  

Мой файл схемы

   public class MySchema : Schema,ISchema
    {
        public MySchema(IServiceProvider provider):base(provider)
        {
            {
                Query = provider.GetRequiredService<MyQuery>();
          
            }
        }
    }
  

И мой запрос

  public class MyQuery : ObjectGraphType
    {
        public MyQuery(MyDbContext db)
        {

            Field<ListGraphType<ApplicationUserType>>("users", "List of Active Users",
                  
                resolve: context => db.ApplicationUsers.Where(u => !u.IsDeleted));
        }
    }

  public class ApplicationUserType : ObjectGraphType<ApplicationUser>
    {
        public ApplicationUserType()
        {
            Field(t => t.Id);
            Field(t => t.UserName);
}}}
  

https://github.com/graphql-dotnet/server/issues/454

Проблема заключалась в том, что я пытался создать службу для этого типа, и я должен был просто создать ее для своего класса I.E

 services.AddSingleton<ISchema, MySchema>();
  

изменено на

 services.AddSingleton<MySchema>();