查询具有可为空的日期时间偏移量属性的链接实体时出现问题

Question

我正在使用simple.odata.client v4来访问我的odata rest api。数据模型非常复杂。我遇到的问题是，我只想获取相关实体满足涉及可为空的日期时间偏移量（OnHandLastUpdate）的属性的条件的实体。实际上在 api 方面，它是一个可为空的日期时间，但我认为 odata v4 会自动转换它。我尝试运行的代码是：

        var items =
oDataClient.For<ClientProductSku>()
    .Filter(x => x.ClientId == clientId && x.Product.SupplierProductSkuClient
        .All(y => y.SupplierProductSku.SupplierProductSkuOnHand
            .Any(z => z.OnHandLastUpdated.HasValue && z.OnHandLastUpdated.Value > DateTimeOffset.Now.AddMinutes(-5))))
    .Expand(UpdateSkuOnhandExpandTables)
    .FindEntriesAsync(annotations)
    .Result;

我得到的错误如下：

  "error":{
    "code":"","message":"The query specified in the URI is not valid. Can only bind segments that are Navigation, Structural, Complex, or Collections. We found a segment 'OnHandLastUpdated' that isn't any of those. Please revise the query.","innererror":{
      "message":"Can only bind segments that are Navigation, Structural, Complex, or Collections. We found a segment 'OnHandLastUpdated' that isn't any of those. Please revise the query.","type":"Microsoft.OData.Core.ODataException","stacktrace":"   at Microsoft.OData.Core.UriParser.Parsers.InnerPathTokenBinder.BindInnerPathSegment(InnerPathToken segmentToken)rn   at Microsoft.OData.Core.UriParser.Parsers.MetadataBinder.BindInnerPathSegment(InnerPathToken token)rn   at Microsoft.OData.Core.UriParser.Parsers.MetadataBinder.Bind(QueryToken token)rn   at Microsoft.OData.Core.UriParser.Parsers.EndPathBinder.DetermineParentNode(EndPathToken segmentToken)rn   at Microsoft.OData.Core.UriParser.Parsers.EndPathBinder.BindEndPath(EndPathToken endPathToken)rn   at Microsoft.OData.Core.UriParser.Parsers.MetadataBinder.BindEndPath(EndPathToken endPathToken)rn   at Microsoft.OData.Core.UriParser.Parsers.MetadataBinder.Bind(QueryToken token)rn   at Microsoft.OData.Core.UriParser.Parsers.BinaryOperatorBinder.GetOperandFromToken(BinaryOperatorKind operatorKind, QueryToken queryToken)rn   at Microsoft.OData.Core.UriParser.Parsers.BinaryOperatorBinder.BindBinaryOperator(BinaryOperatorToken binaryOperatorToken)rn   at Microsoft.OData.Core.UriParser.Parsers.MetadataBinder.BindBinaryOperator(BinaryOperatorToken binaryOperatorToken)rn   at Microsoft.OData.Core.UriParser.Parsers.MetadataBinder.Bind(QueryToken token)rn   at Microsoft.OData.Core.UriParser.Parsers.LambdaBinder.BindExpressionToken(QueryToken queryToken)rn   at Microsoft.OData.Core.UriParser.Parsers.LambdaBinder.BindLambdaToken(LambdaToken lambdaToken, BindingState state)rn   at Microsoft.OData.Core.UriParser.Parsers.MetadataBinder.BindAnyAll(LambdaToken lambdaToken)rn   at Microsoft.OData.Core.UriParser.Parsers.MetadataBinder.Bind(QueryToken token)rn   at Microsoft.OData.Core.UriParser.Parsers.LambdaBinder.BindExpressionToken(QueryToken queryToken)rn   at Microsoft.OData.Core.UriParser.Parsers.LambdaBinder.BindLambdaToken(LambdaToken lambdaToken, BindingState state)rn   at Microsoft.OData.Core.UriParser.Parsers.MetadataBinder.BindAnyAll(LambdaToken lambdaToken)rn   at Microsoft.OData.Core.UriParser.Parsers.MetadataBinder.Bind(QueryToken token)rn   at Microsoft.OData.Core.UriParser.Parsers.BinaryOperatorBinder.GetOperandFromToken(BinaryOperatorKind operatorKind, QueryToken queryToken)rn   at Microsoft.OData.Core.UriParser.Parsers.BinaryOperatorBinder.BindBinaryOperator(BinaryOperatorToken binaryOperatorToken)rn   at Microsoft.OData.Core.UriParser.Parsers.MetadataBinder.BindBinaryOperator(BinaryOperatorToken binaryOperatorToken)rn   at Microsoft.OData.Core.UriParser.Parsers.MetadataBinder.Bind(QueryToken token)rn   at Microsoft.OData.Core.UriParser.Parsers.FilterBinder.BindFilter(QueryToken filter)rn   at Microsoft.OData.Core.UriParser.ODataQueryOptionParser.ParseFilterImplementation(String filter, ODataUriParserConfiguration configuration, IEdmType elementType, IEdmNavigationSource navigationSource)rn   at Microsoft.OData.Core.UriParser.ODataQueryOptionParser.ParseFilter()rn   at System.Web.OData.Query.FilterQueryOption.get_FilterClause()rn   at System.Web.OData.Query.Validators.FilterQueryValidator.Validate(FilterQueryOption filterQueryOption, ODataValidationSettings settings)rn   at System.Web.OData.Query.FilterQueryOption.Validate(ODataValidationSettings validationSettings)rn   at System.Web.OData.Query.Validators.ODataQueryValidator.Validate(ODataQueryOptions options, ODataValidationSettings validationSettings)rn   at System.Web.OData.Query.ODataQueryOptions.Validate(ODataValidationSettings validationSettings)rn   at System.Web.OData.EnableQueryAttribute.ValidateQuery(HttpRequestMessage request, ODataQueryOptions queryOptions)rn   at System.Web.OData.EnableQueryAttribute.ExecuteQuery(Object response, HttpRequestMessage request, HttpActionDescriptor actionDescriptor)rn   at System.Web.OData.EnableQueryAttribute.OnActionExecuted(HttpActionExecutedContext actionExecutedContext)"
    }

我在某处读到，odata v4 中尚未完全支持可为空的日期时间和日期时间偏移量，这可能会导致此问题。无论如何，是否有解决方法来实现上述查询？

Answer 1

我相信这是Simple.OData.Client的当前限制。它具有一个内置的表达式分析器，其工作方式与其他 LINQ 提供程序类似。它将 C# 表达式转换为 OData URI。发生的情况是，它将 HasValue 视为 OnHandLastUpdated 的属性，即 OnHandLastUpdated 被解释为 ComplexType，因此您会收到此错误。

我将在Simple.OData.Client GitHub上注册一个问题，看看这是否可以轻松解决。

我检查了库，看起来您可以像这样重写查询：

     var items =
oDataClient.For<ClientProductSku>()
    .Filter(x => x.ClientId == clientId && x.Product.SupplierProductSkuClient
        .All(y => y.SupplierProductSku.SupplierProductSkuOnHand
            .Any(z => z.OnHandLastUpdated.Value > DateTimeOffset.Now.AddMinutes(-5))))
    .Expand(UpdateSkuOnhandExpandTables)
    .FindEntriesAsync(annotations)
    .Result;

你能试试吗？我相信它应该有效。

Answer 2

FWIW，我正在手动创建表达式树并遇到了同样的问题。我决定四处闲逛并尝试一些东西，并利用@Vagif Abilov的回答将问题缩小到明确使用HasValue属性。

如果您与null进行比较而不是Nullable<DateTimeOffset>.HasValue它有效，并且您不必捏造任何依赖于可为空测试的测试或为 OData 框架提供特殊情况。

因此，按照上面的示例，您应该能够执行以下操作：

 var items = oDataClient.For<ClientProductSku>()
    .Filter(x => x.ClientId == clientId && x.Product.SupplierProductSkuClient
    .All(y => y.SupplierProductSku.SupplierProductSkuOnHand
        .Any(z => z.OnHandLastUpdated != null && 
            z.OnHandLastUpdated.Value > DateTimeOffset.Now.AddMinutes(-5))))
    .Expand(UpdateSkuOnhandExpandTables)
    .FindEntriesAsync(annotations)
    .Result;