我正在使用Microsofts EnableCors属性进行Web API次调用。客户端行为按我的预期运行：例如当Origin无效时，调用返回失败。
然而，当我在方法中加入一个断点时，＆amp;从无效的Origin调用...该方法仍然从上到下执行（即使客户端获得失败的结果）。如果Origin无效，我不希望它执行AT ALL。
我的问题是：
如果EnableCors Origin无效，如何阻止Web API方法执行AT ALL？
帮助我Obi-Wan Kenobi ......你是我唯一的希望。
我的代码看起来像：
[HttpPost]
[EnableCors(origins: "www.zippitydoodah.com", headers: "*", methods: "*")]
public HttpResponseMessage Enqueue(HttpRequestMessage request)
{
// NONE OF THIS SHOULD RUN: If the Origin is bad...but (oddly) it is
TraceHandler.TraceIn(TraceLevel.Info);
string claimId = string.Empty;
ClaimMessage claimMessage = null;
try
{
claimId = GetClaimId(request);
claimMessage = CreateClaimMessage(claimId, segmentClaimFullName);
Enqueue(claimMessage);
TraceHandler.TraceAppend(FORMAT_ENQUEUED_SUCCESS, claimId);
}
catch (Exception ex)
{
TraceHandler.TraceError(ex);
TraceHandler.TraceOut();
EnqueueToPoison(ex, claimMessage);
return Request.CreateResponse(HttpStatusCode.InternalServerError, GetHttpError());
}
TraceHandler.TraceOut();
return Request.CreateResponse(HttpStatusCode.OK, string.Format(FORMAT_ENQUEUED_SUCCESS, claimId));
}
MY CONFIG看起来像：
public static class WebApiConfig
{
#region <Methods>
public static void Register(HttpConfiguration config)
{
// ENABLE CORS
config.EnableCors();
// CREATE ROUTES
config.Routes.MapHttpRoute(
name: "DefaultRpcApiActions",
routeTemplate: "api/{controller}/actions/{action}/{id}",
defaults: new { id = RouteParameter.Optional });
config.Routes.MapHttpRoute(
name: "DefaultApi",
routeTemplate: "api/{controller}/{id}",
defaults: new { id = RouteParameter.Optional });
}
#endregion
}
答案 0 :(得分：2)
事实证明......
预计不会对控制器进行PREVENT调用：MVC或Web API。它只是阻止结果返回到浏览器。它将被执行的方法无论如何......所以你必须通过其他方式阻止执行。
其他方面是什么？
您可以使用AuthorizeAttribute来完成此操作。但我想在ACTION级别进行，所以我选择了ActionFilterAttribute - 并在OnActionExecuting中执行了检查
使用注意事项： ActionFilterAttribute
继续向所有人开放CORS＆amp;然后按行动限制（所以每个人都可以PING）
假设所有来电均来自有效的REFERRER
这意味着来自数据库（我正在做的）的SQL CLR调用之类的东西将无效，因为REFERRER为空（因此，我将在稍后发布更好的解决方案。）
ICorsPolicyProvider没用 - 我正在删除它（但在此处包含它）我看到的所有例子都包括它，但我还没有找到一个被调用的场景。我的构造函数已经创建了CorsPolicy＆amp;该策略在整个呼叫生命周期内都可用...所以ICorsPolicyProvider方法似乎没用（目前）。
TraceHandler实施是我自己的 - 继续＆amp;使用你自己的
必须添加Access-Control-Allow-Origin标头以确保某些客户的预期回复消息行为
这里是代码： ActionFilterAttribute
namespace My.Application.Security
{
using My.Application.Diagnostics;
using System;
using System.Configuration;
using System.Diagnostics;
using System.Net;
using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;
using System.Web.Cors;
using System.Web.Http.Controllers;
using System.Web.Http.Cors;
using System.Web.Http.Filters;
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = false)]
public class EnableWebApiCorsFromAppSettingsAttribute : ActionFilterAttribute, ICorsPolicyProvider
{
#region <Fields & Constants>
private const string EXCEPTION_CONTEXT_NULL = "Access Denied: HttpActionContext cannot be null.";
private const string EXCEPTION_REFERRER_NULL = "Access Denied: Referrer cannot be null.";
private const string FORMAT_INVALID_REFERRER = "Access Denied: '{0}' is not a valid referrer.";
private const string FORMAT_REFERRER = "Referrer: '{0}' was processed for this request.";
private const string FORMAT_REFERRER_FOUND = "Referrer IsFound: {0}.";
private readonly CorsPolicy policy;
#endregion
#region <Constructors>
public EnableWebApiCorsFromAppSettingsAttribute(string appSettingKey, bool allowAnyHeader = true, bool allowAnyMethod = true, bool supportsCredentials = true)
{
policy = new CorsPolicy();
policy.AllowAnyOrigin = false;
policy.AllowAnyHeader = allowAnyHeader;
policy.AllowAnyMethod = allowAnyMethod;
policy.SupportsCredentials = supportsCredentials;
SetValidOrigins(appSettingKey);
if (policy.Origins.Count == 0)
policy.AllowAnyOrigin = true;
}
#endregion
#region <Methods>
#region public
public override void OnActionExecuting(HttpActionContext actionContext)
{
TraceHandler.TraceIn(TraceLevel.Info);
if (actionContext == null)
throw new ArgumentNullException("HttpActionContext");
if (actionContext.Request.Headers.Referrer == null)
actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.Forbidden, EXCEPTION_REFERRER_NULL);
var referrer = actionContext.Request.Headers.Referrer.ToString();
TraceHandler.TraceAppend(string.Format(FORMAT_REFERRER, referrer));
// If no Origins Are Set - Do Nothing
if (policy.Origins.Count > 0)
{
var isFound = policy.Origins.Contains(referrer);
TraceHandler.TraceAppend(string.Format(FORMAT_REFERRER_FOUND, isFound));
if (!isFound)
{
TraceHandler.TraceAppend("IsFound was FALSE");
actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.Forbidden, string.Format(FORMAT_INVALID_REFERRER, referrer));
}
}
TraceHandler.TraceOut();
base.OnActionExecuting(actionContext);
}
public Task<CorsPolicy> GetCorsPolicyAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
if (cancellationToken.CanBeCanceled && cancellationToken.IsCancellationRequested)
return Task.FromResult<CorsPolicy>(null);
return Task.FromResult(policy);
}
#endregion
#region private
private void SetValidOrigins(string appSettingKey)
{
// APP SETTING KEY: <add key="EnableCors.Origins" value="http://www.zippitydoodah.com" />
var origins = string.Empty;
if (!string.IsNullOrEmpty(appSettingKey))
{
origins = ConfigurationManager.AppSettings[appSettingKey];
if (!string.IsNullOrEmpty(origins))
{
foreach (string origin in origins.Split(",;|".ToCharArray(), StringSplitOptions.RemoveEmptyEntries))
policy.Origins.Add(origin);
}
}
}
#endregion
#endregion
}
}
这里是代码的使用： ActionFilterAttribute
namespace My.Application.Web.Controllers
{
using Security;
using My.Application.Diagnostics;
using My.Application.Framework.Configuration;
using My.Application.Models;
using My.Application.Process;
using System;
using System.Configuration;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Messaging;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using System.Web.Http.Cors;
using System.Xml.Linq;
using System.Xml.Serialization;
[EnableCors(origins: "*", headers: "*", methods: "*")]
public class OutboundEventController : ApiControllerBase
{
#region <Actions>
[HttpGet]
public HttpResponseMessage Ping()
{
TraceHandler.TraceIn(TraceLevel.Info);
if (Request.Headers.Referrer == null)
TraceHandler.TraceAppend(MESSAGE_REFERRER_NULL);
if (Request.Headers.Referrer != null)
TraceHandler.TraceAppend(string.Format(FORMAT_REFERRER, Request.Headers.Referrer));
TraceHandler.TraceOut();
return Request.CreateResponse(HttpStatusCode.OK, "Ping back at cha...");
}
[HttpPost]
[EnableWebApiCorsFromAppSettings("EnableCors.Origins")]
public HttpResponseMessage Enqueue(HttpRequestMessage request)
{
TraceHandler.TraceIn(TraceLevel.Info);
if (Request.Headers.Referrer == null)
TraceHandler.TraceAppend(MESSAGE_REFERRER_NULL);
if (Request.Headers.Referrer != null)
TraceHandler.TraceAppend(string.Format(FORMAT_REFERRER, Request.Headers.Referrer));
try
{
// Do Amazing Stuff Here...
TraceHandler.TraceAppend(FORMAT_ENQUEUED_SUCCESS, claimId);
}
catch (Exception ex)
{
TraceHandler.TraceError(ex);
TraceHandler.TraceOut();
EnqueueToPoison(ex, claimMessage);
return Request.CreateResponse(HttpStatusCode.InternalServerError, GetHttpError());
}
TraceHandler.TraceOut();
// FORCE: Correct Header
var response = Request.CreateResponse(HttpStatusCode.OK, string.Format(FORMAT_ENQUEUED_SUCCESS, claimId));
response.Headers.Add("Access-Control-Allow-Origin", "*");
return response;
}
#endregion
private string GetClaimId(HttpRequestMessage request)
{
var stream = request.Content.ReadAsStreamAsync().Result;
var xdoc = XDocument.Load(stream);
var result = GetElementValue(xdoc, "ClaimId");
return result;
}
private ClaimMessage CreateClaimMessage(string claimId, string process)
{
ClaimMessage message = new ClaimMessage();
message.ClaimID = claimId;
message.Process = process;
return message;
}
private void Enqueue(ClaimMessage claimMessage)
{
var queueName = ConfigurationManager.AppSettings[Settings.Messaging.Queue.Name].ToString();
var queue = new MessageQueue(queueName);
queue.DefaultPropertiesToSend.Recoverable = true;
TraceHandler.TraceAppend(FORMAT_QUEUE_NAME, queueName);
MessageQueueTransaction transaction;
transaction = new MessageQueueTransaction();
transaction.Begin();
var message = new System.Messaging.Message();
message.Formatter = new XmlMessageFormatter(new Type[] { typeof(ClaimMessage) });
message.Label = "ClaimID " + claimMessage.ClaimID;
message.Body = claimMessage;
queue.Send(message, transaction);
transaction.Commit();
queue.Close();
}
private void EnqueueToPoison(Exception exception, ClaimMessage claimdata)
{
TraceHandler.TraceIn(TraceLevel.Info);
var poison = ToPoisonMessage(exception, claimdata);
var message = new System.Messaging.Message();
try
{
var poisonQueueName = ConfigurationManager.AppSettings[Settings.Messaging.PoisonQueue.Name].ToString();
TraceHandler.TraceAppend(FORMAT_QUEUE_NAME, poisonQueueName);
if (MessageQueue.Exists(poisonQueueName))
{
var queue = new MessageQueue(poisonQueueName);
queue.DefaultPropertiesToSend.Recoverable = true;
var transaction = new MessageQueueTransaction();
transaction.Begin();
message.Formatter = new XmlMessageFormatter(new Type[] { typeof(PoisonClaimMessage) });
message.Label = "Poison ClaimID " + poison.ClaimID;
var xmlSerializer = new XmlSerializer(poison.GetType());
xmlSerializer.Serialize(message.BodyStream, poison);
queue.Send(message, transaction);
TraceHandler.TraceAppend(FORMAT_ENQUEUED_POISON_SUCCESS, poison.ClaimID);
transaction.Commit();
queue.Close();
}
}
catch(Exception ex)
{
// An error occurred while enqueuing to POISON
var poisonXml = ToString(poison);
TraceHandler.TraceError(ex);
TraceHandler.TraceAppend(poisonXml);
}
finally
{
TraceHandler.TraceOut();
}
}
#endregion
}
}
应用程序设置： ActionFilterAttribute
<appSettings>
<add key="EnableCors.Origins" value="" />
</appSettings>