How to properly create and link a one-to-one relat

问题:

In the OData:Operations documentation, section 2.4 fourth paragraph down, it reads when creating an entity with POST it is also possible to create a link within the same request. However, I'm having trouble trying to make this work. A similar question has been asked about many-to-many linking while creating and it looks like that particular scenario isn't possible without a batch request. Below is the scenario I'm trying to create using this sample OData read write service.

Create a new Product named "Test Product" and link it to Category(0) in a single POST using JSON.

I have tried...

POST /OData/OData.svc/Products HTTP/1.1
Accept: application/json
Content-Type: application/json


{ "ID": 99, "Name": "Test Product", "Description": "Simple Test", "ReleaseDate": "\/Date(1210204800000)\/", "DiscontinuedDate": null, "Rating": 3, "Price": "99.99", "Category":"http://services.odata.org/OData/OData.svc/Categories(0)" }

and ...

POST /OData/OData.svc/Products HTTP/1.1
Accept: application/json
Content-Type: application/json


{ "ID": 99, "Name": "Test Product", "Description": "Simple Test", "ReleaseDate": "\/Date(1210204800000)\/", "DiscontinuedDate": null, "Rating": 3, "Price": "99.99", "Category": {"uri": "http://services.odata.org/OData/OData.svc/Categories(0)"} }

Both which result in failures.

Another example using atom format...

<?xml version="1.0" encoding="utf-8"?>
<entry xmlns:d="http://schemas.microsoft.com/ado/2007/08/dataservices" xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata" xmlns="http://www.w3.org/2005/Atom">
    <title type="text"/>
    <updated>2010-02-27T21:36:47Z</updated>
    <author>
        <name/>
    </author>
    <Link rel="http://schemas.microsoft.com/ado/2007/08/dataservices/related/Category" type="application/atom+xml;type=Entry" title="Category" href="Categories(0)"/>
    <category term="ODataDemo.Product" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme"/>
    <content type="application/xml">
        <m:properties>
            <d:ID m:type="Edm.Int32">99</d:ID>
            <d:Name m:type="Edm.String">New Product</d:Name>
            <d:ReleaseDate m:type="Edm.DateTime">1992-01-01T00:00:00</d:ReleaseDate>
            <d:DiscontinuedDate m:type="Edm.DateTime" m:null="true"/>
            <d:Rating m:type="Edm.Int32">4</d:Rating>
            <d:Price m:type="Edm.Decimal">2.5</d:Price>
        </m:properties>
    </content>
</entry>

The above results in a 201 created, yet no association is created for the new Product linking to the existing Category.

Any help would be appreciated. Thanks in advance.

回答1:

Pablo Castro from Microsoft answered my question. He suggested in the Atom payload I change the capital "L", to lowercase. IE.

<link rel="http://schemas.microsoft.com/ado/2007/08/dataservices/related/Category" type="application/atom+xml;type=entry" title="Category" href="Categories(0)"/>

For the JSON payload you need to include "__metadata" in order for it to work. IE.

{
 Prop1: ...,
 Prop2: ...,
 LinkProp1: { __metadata: { uri: "http://..." } }
}