javascript - Breeze 底层数组在保存时出现 null 错误

Question

当我想要保存我创建的实体时，收到“500(内部服务器错误)底层错误为空”错误消息。

场景:

• 用户打开一个模式窗口，可以在其中创建/编辑博客条目
• 他可以选择标签
• 他还可以创建新标签
• 如果存在尚不存在的标签，系统会自动创建它

当系统想要保存新标签时会发生错误。我真正不明白的是哪个数组为空？!如果我写出新创建的实体，那么我会看到一个由 Breeze 创建的健康实体，并且没有空值，除了一个(博客描述字段，但它不是必填字段)

我做了什么来定位缺陷:

• 仔细检查代码 - 完成
• 检查缓存 - 已完成 - 已禁用
• 谷歌搜索 - 完成 - 看来这是一个非常罕见的问题
• 将代码放入 Controller 中，无论是否是范围问题 - 完成 - 结果是相同的
• 检查 REST Controller ，上次更改是在 71 天前，但在其他情况下运行良好
• sleep ...有时会有所帮助 - 完成，很棒，但没有帮助
• 重新启动机器 - 完成 - 没有任何反应
• 我想我已经没有主意了......

这是代码。里面没有什么新东西。这样的代码在应用程序的其他地方工作没有任何问题。

该函数由 ngTags-input stuff 的 onTagAdding 方法调用，并将其放置在服务中。

function onTagAdding(tag)
        {
            console.log("ontagadding");
            var select = 'id, name';
            var p = new Predicate('name', FilterQueryOp.Equals, tag.name);

            datacontext.tag.getAll(select, p).then(function (result)
            {
                if (result.length < 1)
                {
                    //add new tag
                    var newTag = datacontext.tag.create();
                    newTag.name = tag.name;
                    console.log('tag ontagadding', tag);
                    console.log('newTag  ontagadding', newTag);
                }

                datacontext.save().then(function (saveResult)
                {
                    console.log('saved tag  ontagadding');
                    if (typeof (saveResult) !== 'undefined')
                    {
                        lastSavedTag = saveResult.entities[0];
                    }
                });
            });
        }

Controller 调用服务方法:

function onTagAdding(tag)
        {
            dataServiceTagHelper.onTagAdding(tag);
        }

请求负载:

"entities": [{
    "Id": -1,
    "Name": "sdfsdfsdf",
    "Desc": null,
    "entityAspect": {
        "entityTypeName": "Tag:#SayusiAndo.DiLib.Model.Model.Db.Model.Blog",
        "defaultResourceName": "Tags",
        "entityState": "Added",
        "originalValuesMap": {

        },
        "autoGeneratedKey": {
            "propertyName": "Id",
            "autoGeneratedKeyType": "Identity"
        }
    }
}],
"saveOptions": {

}

以下是完整的错误消息:

Error: [DiLib Error]  save failed!The underlying array is null.
    at createError (http://dev.dilib.local/ui/scripts/breeze.debug.js:15821:15)
    at handleHttpError (http://dev.dilib.local/ui/scripts/breeze.debug.js:15811:15)
    at Object.breeze.AbstractDataServiceAdapter.proto.saveChanges.ajaxImpl.ajax.error (http://dev.dilib.local/ui/scripts/breeze.debug.js:15687:9)
    at errorFn (http://dev.dilib.local/ui/scripts/breeze.debug.js:16026:14)
    at http://dev.dilib.local/ui/scripts/angular.js:9415:11
    at processQueue (http://dev.dilib.local/ui/scripts/angular.js:13248:27)
    at http://dev.dilib.local/ui/scripts/angular.js:13264:27
    at Scope.$get.Scope.$eval (http://dev.dilib.local/ui/scripts/angular.js:14466:28)
    at Scope.$get.Scope.$digest (http://dev.dilib.local/ui/scripts/angular.js:14282:31)
    at Scope.$get.Scope.$apply (http://dev.dilib.local/ui/scripts/angular.js:14571:24)

服务器端:

StackTrace: "   at System.ArraySegment`1.System.Collections.IEnumerable.GetEnumerator()
↵   at System.Data.Entity.Core.Objects.EntityEntry.TakeSnapshotOfRelationships()
↵   at System.Data.Entity.Core.Objects.ObjectContext.AddObject(String entitySetName, Object entity)
↵   at Breeze.ContextProvider.EF6.EFContextProvider`1.AddObjectStateEntry(EFEntityInfo entityInfo)
↵   at Breeze.ContextProvider.EF6.EFContextProvider`1.ProcessEntity(EFEntityInfo entityInfo)
↵   at Breeze.ContextProvider.EF6.EFContextProvider`1.ProcessSaves(Dictionary`2 saveMap)
↵   at Breeze.ContextProvider.EF6.EFContextProvider`1.SaveChangesCore(SaveWorkState saveWorkState)
↵   at Breeze.ContextProvider.ContextProvider.OpenAndSave(SaveWorkState saveWorkState)
↵   at Breeze.ContextProvider.ContextProvider.SaveChanges(JObject saveBundle, TransactionSettings transactionSettings)
↵   at SayusiAndo.DiLib.Service.WebApi.Controllers.Breeze.DiLibController.SaveChanges(JObject saveBundle) in c:\PROJECTS\sayusiando.visualstudio.com\DiLib\Dev\branches\DiLib-Dev\src\DigitalLibrary\App\DiLib\Service\DiLib.Service.WebApi\Controllers\Breeze\DiLibController.cs:line 29
↵   at lambda_method(Closure , Object , Object[] )
↵   at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.<>c__DisplayClass10.<GetExecutor>b__9(Object instance, Object[] methodParameters)
↵   at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ExecuteAsync(HttpControllerContext controllerContext, IDictionary`2 arguments, CancellationToken cancellationToken)
↵--- End of stack trace from previous location where exception was thrown ---
↵   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
↵   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
↵   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
↵   at System.Web.Http.Controllers.ApiControllerActionInvoker.<InvokeActionAsyncCore>d__0.MoveNext()
↵--- End of stack trace from previous location where exception was thrown ---
↵   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
↵   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
↵   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
↵   at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__5.MoveNext()
↵--- End of stack trace from previous location where exception was thrown ---
↵   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
↵   at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__5.MoveNext()
↵--- End of stack trace from previous location where exception was thrown ---
↵   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
↵   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
↵   at System.Web.Http.Filters.ActionFilterAttribute.<ExecuteActionFilterAsyncCore>d__0.MoveNext()
↵--- End of stack trace from previous location where exception was thrown ---
↵   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
↵   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
↵   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
↵   at System.Web.Http.Controllers.ActionFilterResult.<ExecuteAsync>d__2.MoveNext()
↵--- End of stack trace from previous location where exception was thrown ---
↵   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
↵   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
↵   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
↵   at System.Web.Http.Controllers.ExceptionFilterResult.<ExecuteAsync>d__0.MoveNext()
↵--- End of stack trace from previous location where exception was thrown ---
↵   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
↵   at System.Web.Http.Controllers.ExceptionFilterResult.<ExecuteAsync>d__0.MoveNext()
↵--- End of stack trace from previous location where exception was thrown ---
↵   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
↵   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
↵   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
↵   at System.Web.Http.Dispatcher.HttpControllerDispatcher.<SendAsync>d__1.MoveNext()"

感谢您提前提供的任何帮助!

Answer 1

我找到了。我犯了两个错误。

• 当我为对象模型创建 C# 类时，我认为需要一个数组来存储 BlogEntryTags，因此我输入“array”并按 Enter 键。 Resharper 试图提供帮助，因此它放置了 ArraySegment 而不是 List。到目前为止，它没有出现任何缺陷，因为我还没有使用过应用程序的这一部分。
• 当我检查可能的问题时，我并没有检查breeze和db之间所有可能的问题。

现在，一切正常。

这是变化: