Question

我正在制作一个基于请求使用不同EDM模型的Web服务。为了实现这一目标，我的目标是从XML加载模型，但是我的测试表明我的序列化方法似乎丢失了数据（看起来真的很臭）。

我有以下API控制器方法来测试反序列化，写入xml并再次回读

public IHttpActionResult Post()
{
    IEnumerable<EdmError> errors;
    var model = FromXml(await Request.Content.ReadAsStringAsync(), out errors);

    var parts = ToXml(model);

    model = FromParts(parts);

    var odataProperties = Request.ODataProperties();
    odataProperties.Model = model;
    return Ok(GetMetadata());
}

public IEdmModel FromXml(string xml, out IEnumerable<EdmError> errors)
{
    var readers = new List<XmlReader>();
    var disposables = new List<IDisposable>();
    try
    {
        //Have no idea if this is correct but only way I was able to make it work
        XmlDocument doc = new XmlDocument();
        doc.LoadXml(xml);
        doc.GetElementsByTagName("Schema").Cast<XmlNode>().ToList().ForEach(node =>
        {
            var stringReader = new StringReader(node.OuterXml);
            var xmlReader = XmlReader.Create(stringReader);
            readers.Add(xmlReader);
            disposables.Add(xmlReader);
            disposables.Add(stringReader);
        });

        IEdmModel model;
        CsdlReader.TryParse(readers.AsEnumerable(), out model, out errors);

        return model;
    }
    finally
    {
        disposables.ForEach(r => r.Dispose());
    }
}

//Really don't thing this is right but couldn't write the model
//But passing the model into TryWriteCsdl gives edm error Single file provided but model cannot be serialized into single file
public static List<string> ToXml(IEdmModel model)
{

    IEnumerable<EdmError> errors = new List<EdmError>();
    var xmlParts = new List<string>();
    foreach (var schema in model.SchemaElements)
    {
        var xmlBuilder = new StringBuilder();
        var tempModel = new EdmModel();
        tempModel.AddElement(schema);
        using (var xmlWriter = XmlWriter.Create(xmlBuilder, new XmlWriterSettings() { Encoding = Encoding.UTF32 }))
        {
            tempModel.TryWriteCsdl(xmlWriter, out errors);
        }
        xmlParts.Add(xmlWriter.ToString());
    }

    return xmlParts;
}

public IEdmModel FromParts(List<string> parts)
{
    var readers = new List<XmlReader>();
    var disposables = new List<IDisposable>();
    EdmEntityContainer entityContainer = null;
    try
    {
        IEdmModel model;
        IEnumerable<EdmError> errors;
        await
            parts.ForEachAsync(f =>
            {
                var stringReader = new StringReader(f);
                var xmlReader = XmlReader.Create(stringReader);
                readers.Add(xmlReader);
                disposables.Add(xmlReader);
                disposables.Add(stringReader);
            });
        CsdlReader.TryParse(readers, out model, out errors);

        return model ;
    }
    finally
    {
        disposables.ForEach(r => r.Dispose());
    }
}

当我发送以下作为请求正文时

<?xml version="1.0" encoding="utf-8"?>
<edmx:Edmx Version="4.0" xmlns:edmx="http://docs.oasis-open.org/odata/ns/edmx">
  <edmx:Reference Uri="http://docs.oasis-open.org/odata/odata/v4.0/os/vocabularies/Org.OData.Core.V1.xml">
    <edmx:Include Alias="Core" Namespace="Org.OData.Core.V1"/>
  </edmx:Reference>
  <edmx:DataServices>
    <Schema Namespace="NorthwindModel" xmlns="http://docs.oasis-open.org/odata/ns/edm">
      <EntityType Name="Item">
        <Key>
          <PropertyRef Name="ItemID"/>
        </Key>
        <Property Name="ItemID" Type="Edm.Int32" Nullable="false">
          <Annotation Term="Core.Computed" Bool="true" />
        </Property>
        <Property Name="ItemName" Type="Edm.String"/>
      </EntityType>
    </Schema>
    <Schema Namespace="ODataWebExperimental.Northwind.Model" xmlns="http://docs.oasis-open.org/odata/ns/edm">
      <EntityContainer xmlns:p4="http://schemas.microsoft.com/ado/2009/02/edm/annotation" Name="NorthwindEntities" p4:LazyLoadingEnabled="true">
        <EntitySet Name="Items" EntityType="NorthwindModel.Item" />
      </EntityContainer>
    </Schema>
  </edmx:DataServices>
</edmx:Edmx>

我得到了这个回复

<?xml version="1.0" encoding="utf-8"?>
<edmx:Edmx Version="4.0" 
xmlns:edmx="http://docs.oasis-open.org/odata/ns/edmx">
    <edmx:DataServices>
        <Schema Namespace="NorthwindModel" 
        xmlns="http://docs.oasis-open.org/odata/ns/edm">
            <EntityType Name="Item">
                <Key>
                    <PropertyRef Name="ItemID" />
                </Key>
                <Property Name="ItemID" Type="Edm.Int32" Nullable="false" />
                <Property Name="ItemName" Type="Edm.String" />
            </EntityType>
        </Schema>
        <Schema Namespace="ODataWebExperimental.Northwind.Model" 
        xmlns="http://docs.oasis-open.org/odata/ns/edm">
            <EntityContainer Name="NorthwindEntities">
                <EntitySet Name="Items" EntityType="NorthwindModel.Item" />
            </EntityContainer>
        </Schema>
    </edmx:DataServices>
</edmx:Edmx>

除了<Annotation Term="Core.Computed" Bool="true" />行消失之外，这几乎是正确的。我需要确保序列化/反序列化

中没有数据丢失

我序列化模型的方式对我来说似乎不对，但不确定我该怎么做

XML的EDM模型

0 个答案: