在消息处理程序中添加属性值

Question

我想在asp.net webapi的消息处理程序中添加属性值.方案是我实现webapi,其中authenticationToken是不同请求的一部分,但客户端要求我接受请求标头中的令牌.但是一些应用程序已经在使用这个api在请求体中发送令牌.所以我不想改变实施.我想读取请求标头,如果它包含标头,则将该值分配给请求的属性.可能吗？

Answer 1

是的,它可以修改您的要求uri和formdata在消息处理程序.这是一个例子,你可以试试这个.我添加了一个class APIKeyHandler来处理这个,并添加了我的处理程序WebApiConfig.我已经在我的Git中上传了一个解决方案,您可以在MessageHandler中使用Modify Request Body从示例WebAPI进行检查

代码WebApiConfig:

public static class WebApiConfig
{
    public static void Register(HttpConfiguration config)
    {
        System.Web.Routing.RouteTable.Routes.MapHttpRoute(
            name: "DefaultApi",
            routeTemplate: "api/{controller}/{action}/{id}",
            defaults: new { id = RouteParameter.Optional }
        );

        //add the handler class in WebApiConfig
        config.MessageHandlers.Add(new APIKeyHandler());
    }
}

代码APIKeyHandler:

public class APIKeyHandler : DelegatingHandler
{
    protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
    {
        var formData = await request.Content.ReadAsFormDataAsync();
        if (request.Method.Method.Equals("POST"))
        {
            request.Content = new FormUrlEncodedContent(ModifyYourFormData(formData, request));
        }
        request.RequestUri = new Uri(ModifyYourURI(request.RequestUri.ToString(), request), UriKind.Absolute);

        return await base.SendAsync(request, cancellationToken);
    }

    public IEnumerable<KeyValuePair<string, string>> ModifyYourFormData(NameValueCollection source, HttpRequestMessage request)
    {
        //Add your logic here

        string Authorized = "";
        try
        {
            Authorized = request.Headers.GetValues("AuthorizedKey").FirstOrDefault();
        }
        catch (Exception ex)
        {

        }

        List<KeyValuePair<string, string>> formData;
        formData = source.AllKeys.SelectMany(
            source.GetValues,
            (k, v) => new KeyValuePair<string, string>(k, v)).ToList();

        if (!string.IsNullOrEmpty(Authorized))
        {
            formData.Insert(0, new KeyValuePair<string, string>("AuthorizedKey", Authorized)); 
        }

        return formData;
    }

    public string ModifyYourURI(string uri, HttpRequestMessage request)
    {
        //Add your logic here

        string Authorized = "";
        try
        {
            Authorized = request.Headers.GetValues("AuthorizedKey").FirstOrDefault();
        }
        catch (Exception ex)
        {

        }

        if (!string.IsNullOrEmpty(Authorized))
        {
            return uri + "?AuthorizedKey="+ Authorized;
        }
        else
        {
            return uri;
        }
    }
}

代码ExampleAPIController:

public class ExampleAPIController : ApiController
{
    public async Task<string> Post()
    {
        string returnValue = "OK";

        var formKeyValueData = await Request.Content.ReadAsFormDataAsync();

        string AuthorizedKey = formKeyValueData["AuthorizedKey"];

        return returnValue;
    }

    public string Get(string AuthorizedKey)
    {
        string returnValue = "OK";
        return returnValue;
    }
}

POST请求调用示例:

GET请求呼叫示例: