如何在 ASP.NET Web API 实现中将数组传递给 OData 函数？

Question

OData V4 的规范声明它必须是可能的： https://issues.oasis-open.org/browse/ODATA-636.

"复杂类型和数组只能通过 参数别名”

当我尝试传递带有 OData 参数别名的数组时，会发生异常。

/TestEntities/NS.TestFunction(ArrayHere=@p)?@p=[1,2,3]

结果：

无法将“EdmValidCoreModelPrimitiveType”类型的对象转换为类型 'Microsoft.OData.Edm.IEdmStructuredType

有趣的是，元数据文档在这种情况下是正确组成的：

<Function Name="TestFunction" IsBound="true">
  <Parameter Name="bindingParameter" Type="Collection(NS.TestEntity)"/>
  <Parameter Name="ArrayHere" Type="System.Int32[]"/>
  <ReturnType Type="Collection(NS.TestEntity)"/>
</Function>

ASP.NET MVC Web API 2 OData 是否可以在查询字符串中将数组传递给 OData 函数？

更新：

这是构建 EDM 模型和控制器的代码。

 var builder = new ODataConventionModelBuilder();

 builder.Namespace = "NS";

 builder.EntitySet<TestEntity>("TestEntities");

 builder.EntityType<TestEntity>().Collection
    .Function("TestFunction")
    .ReturnsCollectionFromEntitySet<TestEntity>("TestEntities")
    .Parameter<int[]>("ArrayHere");

控制器：

public class TestEntitiesController : ODataController
{
    public IEnumerable<TestEntity> TestFunction(int[] arrayHere)
    {
        throw new NotImplementedException();
    }
}

用[FromODataUri]标记参数不能解决问题。

更新 2：

这是堆栈跟踪：

at Microsoft.OData.Core.UriParser.TypePromotionUtils.CanConvertTo(SingleValueNode sourceNodeOrNull, IEdmTypeReference sourceReference, IEdmTypeReference targetReference)
at Microsoft.OData.Core.UriParser.Parsers.MetadataBindingUtils.ConvertToTypeIfNeeded(SingleValueNode source, IEdmTypeReference targetTypeReference)
at Microsoft.OData.Core.UriParser.Parsers.FunctionCallBinder.BindSegmentParameters(ODataUriParserConfiguration configuration, IEdmOperation functionOrOpertion, ICollection`1 segmentParameterTokens)
at Microsoft.OData.Core.UriParser.Parsers.ODataPathParser.TryBindingParametersAndMatchingOperation(String identifier, String parenthesisExpression, IEdmType bindingType, ODataUriParserConfiguration configuration, ICollection`1& boundParameters, IEdmOperation& matchingOperation)
at Microsoft.OData.Core.UriParser.Parsers.ODataPathParser.TryCreateSegmentForOperation(ODataPathSegment previousSegment, String identifier, String parenthesisExpression)
at Microsoft.OData.Core.UriParser.Parsers.ODataPathParser.CreateNextSegment(String text)
at Microsoft.OData.Core.UriParser.Parsers.ODataPathParser.ParsePath(ICollection`1 segments)
at Microsoft.OData.Core.UriParser.Parsers.ODataPathFactory.BindPath(ICollection`1 segments, ODataUriParserConfiguration configuration)
at Microsoft.OData.Core.UriParser.ODataUriParser.ParsePathImplementation()
at Microsoft.OData.Core.UriParser.ODataUriParser.Initialize()
at System.Web.OData.Routing.DefaultODataPathHandler.Parse(IEdmModel model, String serviceRoot, String odataPath, Boolean enableUriTemplateParsing)
at System.Web.OData.Routing.DefaultODataPathHandler.Parse(IEdmModel model, String serviceRoot, String odataPath)
at System.Web.OData.Routing.ODataPathRouteConstraint.Match(HttpRequestMessage request, IHttpRoute route, String parameterName, IDictionary`2 values, HttpRouteDirection routeDirection)
at System.Web.Http.Routing.HttpRoute.ProcessConstraint(HttpRequestMessage request, Object constraint, String parameterName, HttpRouteValueDictionary values, HttpRouteDirection routeDirection)
at System.Web.Http.Routing.HttpRoute.ProcessConstraints(HttpRequestMessage request, HttpRouteValueDictionary values, HttpRouteDirection routeDirection)
at System.Web.Http.Routing.HttpRoute.GetRouteData(String virtualPathRoot, HttpRequestMessage request)
at System.Web.Http.WebHost.Routing.HttpWebRoute.GetRouteData(HttpContextBase httpContext)

Answer 1

假设您使用的是 OData V4，您需要在注册函数时使用 CollectionParameter，并且您缺少 arrayHere 参数上的 [FromODataUri]。另外，请尝试使用 IEnumerable<int> 而不是数组。

var builder = new ODataConventionModelBuilder();

 builder.Namespace = "NS";

 builder.EntitySet<TestEntity>("TestEntities");

 builder.EntityType<TestEntity>().Collection
    .Function("TestFunction")
    .ReturnsCollectionFromEntitySet<TestEntity>("TestEntities")
    .CollectionParameter<int>("ArrayHere");

像这样在控制器中使用函数...

[HttpGet]
public async Task<IHttpActionResult> TestFunction([FromODataUri] IEnumerable<int> ArrayHere)
{
    // Do stuff
}

现在您可以提出诸如...之类的请求

http://yourRestService/API/TestEntities/NS.TestFunction(ArrayHere=[1,2,3])

请注意，您也可以接受复杂类型的数组。您必须对数组的 json 进行 url 编码并使用参数别名，这样您最终会得到这样的结果...

 builder.EntityType<TestEntity>().Collection
    .Function("TestFunction2")
    .ReturnsCollectionFromEntitySet<TestEntity>("TestEntities")
    .CollectionParameter<person>("ArrayHere");

和

[HttpGet]
public async Task<IHttpActionResult> TestFunction2([FromODataUri] IEnumerable<person> ArrayHere)
{
    // Do stuff
}

http://yourRestService/API/TestEntities/NS.TestFunction2(ArrayHere=@ArrayData)?@ArrayData=%5B%7B%22FirstName%22%3A%22Bob%22%2C+%22LastName%22%3A%22Dole%22%7D%2C%7B%22FirstName%22%3A%22Bill%22%2C+%22LastName%22%3A%22Clinton%22%7D%5D

Answer 2

我不知道您当前使用的是哪个版本的 OData，但这是我实施的适用于 v4 并将简单数组传递给 OData Action 方法的解决方案

在您的 WebConfig.cs 中

ODataModelBuilder builder = new ODataConventionModelBuilder();
builder.EntitySet<TestEntity>("TestEntities");

builder.Namespace = "NS";

builder.EntityType<TestEntity>()
        .Action("TestAction")
    .CollectionParameter<string>("ArrayHere");    

这里是你的控制器方法

[HttpPost]
public async Task<IHttpActionResult> TestAction([FromODataUri] int key, ODataActionParameters parameters)
{
    // Do your thing here..
    var invites = parameters["ArrayHere"] as IEnumerable<string>;
}

生成的 API 端点请求应如下所示：

POST http://localhost/odata/TestEntities(1)/NS.TestAction HTTP/1.1
Content-type: application/json
Host: localhost:49255
Content-Length: 37

{"ArrayHere":["hello", "world"]}    

我多次遇到这个特殊问题，但无法使其适用于 OData 函数。我挖得更深一点，发现CollectionParameter<>() 方法可以解决所有问题。我没有回去尝试Function，因为我并没有真正看到需要。希望对你有所帮助