如何读取发布到 REST Web 服务的 HttpRequest 正文 - C# WCF

Question

我有一个调用 REST Web 服务的 Apex 类（SalesForce 中的一个类）。

public class WebServiceCallout 
{
    @future (callout=true)
    public static void sendNotification(String aStr) 
    {
        HttpRequest req = new HttpRequest();
        HttpResponse res = new HttpResponse();
        Http http = new Http();

        req.setEndpoint('http://xx.xxx.xxx.xx:41000/TestService/web/test');
        req.setMethod('POST');
        req.setHeader('Content-Type', 'application/json');
        req.setBody(aStr); // I want to read this in the web service

        try 
        {
            res = http.send(req);
        } 
        catch(System.CalloutException e) 
        {
            System.debug('Callout error: '+ e);
            System.debug(res.toString());
        }
    }
}

REST Web 服务（C#、WCF）如下所示：

public interface ITestService
{
    [OperationContract]
    [WebInvoke(Method = "POST",
     ResponseFormat = WebMessageFormat.Json,
     BodyStyle = WebMessageBodyStyle.Bare,
     UriTemplate = "/test")]
    string Test(string aStr);
}

Test() 方法执行原始操作。

当我跑步时

WebServiceCallout.sendNotification("a test message")

POST 进入 Web 服务，但我如何才能读取 HttpRequest req 的 body 中设置的内容，而 sendNotification()方法——req.setBody(aStr);?

即string Test(string aStr);的参数应该是什么？

我是否需要在WebInvoke 或App.config（例如binding）中指定任何其他配置/属性？

Answer 1

如果要读取传入请求的原始正文，则应将参数的类型定义为Stream，而不是string。下面的代码显示了一种实现场景的方法，http://blogs.msdn.com/b/carlosfigueira/archive/2008/04/17/wcf-raw-programming-model-receiving-arbitrary-data.aspx 的帖子有更多关于这种“原始”模式的信息。

public class StackOverflow_25377059
{
    [ServiceContract]
    public interface ITestService
    {
        [OperationContract]
        [WebInvoke(Method = "POST",
         ResponseFormat = WebMessageFormat.Json,
         BodyStyle = WebMessageBodyStyle.Bare,
         UriTemplate = "/test")]
        string Test(Stream body);
    }

    public class Service : ITestService
    {
        public string Test(Stream body)
        {
            return new StreamReader(body).ReadToEnd();
        }
    }

    class RawMapper : WebContentTypeMapper
    {
        public override WebContentFormat GetMessageFormatForContentType(string contentType)
        {
            return WebContentFormat.Raw;
        }
    }

    public static void Test()
    {
        var baseAddress = "http://" + Environment.MachineName + ":8000/Service";
        var host = new ServiceHost(typeof(Service), new Uri(baseAddress));
        var binding = new WebHttpBinding { ContentTypeMapper = new RawMapper() };
        host.AddServiceEndpoint(typeof(ITestService), binding, "").Behaviors.Add(new WebHttpBehavior());
        host.Open();
        Console.WriteLine("Host opened");

        var req = (HttpWebRequest)HttpWebRequest.Create(baseAddress + "/test");
        req.Method = "POST";
        req.ContentType = "application/json";
        var reqStream = req.GetRequestStream();
        var body = "a test message";
        var bodyBytes = new UTF8Encoding(false).GetBytes(body);
        reqStream.Write(bodyBytes, 0, bodyBytes.Length);
        reqStream.Close();
        var resp = (HttpWebResponse)req.GetResponse();
        Console.WriteLine("HTTP/{0} {1} {2}", resp.ProtocolVersion, (int)resp.StatusCode, resp.StatusDescription);
        foreach (var header in resp.Headers.AllKeys)
        {
            Console.WriteLine("{0}: {1}", header, resp.Headers[header]);
        }

        Console.WriteLine();
        Console.WriteLine(new StreamReader(resp.GetResponseStream()).ReadToEnd());
        Console.WriteLine();
    }
}

顺便说一句，您的传入请求在技术上不正确 - 您说（通过 Content-Type）您正在发送 JSON，但请求正文 (a test message) 不是有效的 JSON 字符串（它应该被包装在引号中 - "a test message" 改为 JSON 字符串）。