Gremlin 查询执行错误：无法添加分区键属性值为“null”的顶点

Question

我正在尝试将 Azure Cosmos DB 用于 Apache Gremlin。但是，当我第一次尝试向数据库添加新顶点时，它会抛出错误。我确认我已经设置了所需的属性，并且它们不能为空。

这是完整的错误：

fail: Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware[1]
      An unhandled exception has occurred while executing the request.
      ExRam.Gremlinq.Core.Execution.GremlinQueryExecutionException: Executing query 827bd7f2-3ae7-4b70-93ae-ef0ef18a2951 failed.
       ---> Gremlin.Net.Driver.Exceptions.ResponseException: ServerEvaluationError:

ActivityId : 7be8d7fe-6e53-4970-9418-84c6835c4b0a
ExceptionType : GraphRuntimeException
ExceptionMessage :
        Gremlin Query Execution Error: Cannot add a vertex where the partition key property has value 'null'.
        GremlinRequestId : 827bd7f2-3ae7-4b70-93ae-ef0ef18a2951
        Context : graphcompute
        Scope : graphcomp-execquery
        GraphInterOpStatusCode : GraphRuntimeError
        HResult : 0x80131500

         --- End of inner exception stack trace ---
         at ExRam.Gremlinq.Providers.Core.GremlinqClientFactory.GremlinQueryExecutorImpl.<Execute>g__Core|3_0[T](GremlinQueryExecutorImpl this, GremlinQueryExecutionContext context, CancellationToken ct)+MoveNext() in /_/src/Providers.Core/Factory/GremlinqClientFactory.cs:line 222
         at ExRam.Gremlinq.Providers.Core.GremlinqClientFactory.GremlinQueryExecutorImpl.<Execute>g__Core|3_0[T](GremlinQueryExecutorImpl this, GremlinQueryExecutionContext context, CancellationToken ct)+MoveNext() in /_/src/Providers.Core/Factory/GremlinqClientFactory.cs:line 217
         at ExRam.Gremlinq.Providers.Core.GremlinqClientFactory.GremlinQueryExecutorImpl.<Execute>g__Core|3_0[T](GremlinQueryExecutorImpl this, GremlinQueryExecutionContext context, CancellationToken ct)+System.Threading.Tasks.Sources.IValueTaskSource<System.Boolean>.GetResult()
         at ExRam.Gremlinq.Core.AsyncEnumerable.FirstAsync[TSource](IAsyncEnumerable`1 source, CancellationToken ct) in /_/src/Core/Extensions/AsyncEnumerable.cs:line 32
         at ExRam.Gremlinq.Core.AsyncEnumerable.FirstAsync[TSource](IAsyncEnumerable`1 source, CancellationToken ct) in /_/src/Core/Extensions/AsyncEnumerable.cs:line 32
         at AzheirAPI.Controllers.AccountsController.Register(Dictionary`2 request) in D:\GodotProjects\azheir\AzheirWebsite\AzheirAPI\Controllers\AccountsController.cs:line 267
         at lambda_method19(Closure, Object)
         at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.AwaitableObjectResultExecutor.Execute(ActionContext actionContext, IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
         at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeActionMethodAsync>g__Awaited|12_0(ControllerActionInvoker invoker, ValueTask`1 actionResultValueTask)
         at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeNextActionFilterAsync>g__Awaited|10_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
         at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context)
         at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
         at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeInnerFilterAsync>g__Awaited|13_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
         at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeFilterPipelineAsync>g__Awaited|20_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
         at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
         at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
         at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
         at Swashbuckle.AspNetCore.SwaggerUI.SwaggerUIMiddleware.Invoke(HttpContext httpContext)
         at Swashbuckle.AspNetCore.Swagger.SwaggerMiddleware.Invoke(HttpContext httpContext, ISwaggerProvider swaggerProvider)
         at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
         at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddlewareImpl.Invoke(HttpContext context)
info: Microsoft.Azure.SignalR.ServiceConnection[12]

这是 Program.cs 类，我在其中告诉查询源如何找到我的 PartitionKey：

            var hostname = builder.Configuration["Azure:CosmosDB:Gremlin:Hostname"]!;
            var port = builder.Configuration["Azure:CosmosDB:Gremlin:Port"]!;
            var authentication = builder.Configuration["Azure:CosmosDB:Gremlin:AuthKey"]!;
            var database = builder.Configuration["Azure:CosmosDB:Gremlin:Database"]!;
            var graph = builder.Configuration["Azure:CosmosDB:Gremlin:Graph"]!;
            var fullUri = $"wss://{hostname}:{port}/";

            IGremlinQuerySource gremlinQuerySource = GremlinQuerySource.g
               .UseCosmosDb<Vertex, Edge>(configurator => configurator
                    .At(new Uri(fullUri))
                    .OnDatabase(database)
                    .OnGraph(graph)
                    .WithPartitionKey(x => x.PartitionKey!)
                    .AuthenticateBy(authentication)
                    .UseNewtonsoftJson());

            builder.Services.AddSingleton(gremlinQuerySource);

这是我定义 Vertex 类及其继承的方式：

    public class Vertex
    {
        public string? Id { get; set; }

        public string? PartitionKey { get; set; } = "/AzheirGraph";
    }

    public class Edge
    {
        public string? Id { get; set; }
        public string? PartitionKey { get; set; } = "/AzheirGraph";
    }

    public class Account : Vertex
    {
        public string Avatar { get; set; } = string.Empty;
        public required string Email { get; set; } = string.Empty;
        public required string Password { get; set; } = string.Empty;
        public string FullName { get; set; } = string.Empty;
        public string PhoneNumber { get; set; } = string.Empty;
        public DateTime DateOfBirth { get; set; } = DateTime.MaxValue;
        public DateTime CreatedDate { get; set; } = DateTime.UtcNow;
        public Gender Gender { get; set; } = Gender.Unknown;
        public int Points { get; set; } = 0;
        public bool IsConfirmed { get; set; } = false;
        public bool NewsletterSubscription { get; set; } = false;
    }

我的 csproj 文件

    <PackageReference Include="ExRam.Gremlinq.Core" Version="12.10.0" />
    <PackageReference Include="ExRam.Gremlinq.Core.AspNet" Version="12.10.0" />
    <PackageReference Include="ExRam.Gremlinq.Providers.Core" Version="12.10.0" />
    <PackageReference Include="ExRam.Gremlinq.Providers.CosmosDb" Version="12.10.0" />
    <PackageReference Include="ExRam.Gremlinq.Providers.CosmosDb.AspNet" Version="12.10.0" />
    <PackageReference Include="ExRam.Gremlinq.Providers.GremlinServer" Version="12.10.0" />
    <PackageReference Include="ExRam.Gremlinq.Providers.GremlinServer.AspNet" Version="12.10.0" />
    <PackageReference Include="ExRam.Gremlinq.Support.NewtonsoftJson" Version="12.10.0" />
    <PackageReference Include="ExRam.Gremlinq.Support.NewtonsoftJson.AspNet" Version="12.10.0" />
    <PackageReference Include="FlakeId" Version="1.2.0" />
    <PackageReference Include="Gremlin.Net" Version="3.7.2" />

以下是它的使用方法：

            AzheirAPI.Elements.Account newAccount = new()
            {
                Id = Guid.NewGuid().ToString(),
                Email = requestEmail,
                Password = Argon2.Hash(requestPassword),
            };

           // This line causing: Gremlin Query Execution Error: Cannot add a vertex where the partition key property has value 'null'.
            Elements.Account createdAccount = await gremlinQuerySource.AddV(newAccount).FirstAsync();

            Console.WriteLine($"createdAccount: {createdAccount}");

我尝试删除 Azure 上的图表，然后使用设置为“/AzheirGraph”的 PartitionKey 重新创建它。我还尝试从该键中删除“/”，但这也不起作用。请指出我可能做错了什么。这是我第一次与 Cosmos DB 和 Gremlin 交互，所以我不知道我可能做错了什么。

Answer 1

更改以下代码

public string? PartitionKey { get; set; } = "/AzheirGraph";

到

public string? AzheirGraph { get; set; }

基本上，分区键的名称必须是 Vertex 基类属性的名称。确保拼写正确。

我的分区键名称是“elementTypeId”，它是一个 int 值。

所以我将 Vertex 类属性更改为；

public int elementTypeId { get; set; } = 0;

并且成功了。我希望这对您有帮助，这对我有用。